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Ziegler, M.Sc., Philipp

Philipp Ziegler, M.Sc.

Research associate
Institute for Power Electronics and Electrical Drives

Contact

+49 711 685 67383
+49 711 685 67378
Email

Pfaffenwaldring 47
70569 Stuttgart
Deutschland
Room: 1.285, ETI 1

Office Hours

Only with an appointment

Publications

2023
1. Ziegler, P., Linzmaier, J., Haarer, J., Marx, P., Eckstein, M., Roth-Stielow, J.: Wide Bandwidth Current Sensors and the Influence on the Switching Loss Characterization. In: 2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia). pp. 1181–1188 (2023).
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  @inproceedings{10213817, abstract = {Due to their outstanding properties, wide bandgap semiconductor devices enable better performance and efficiency in power electronic circuits compared to silicon devices. However, characterizing the switching loss of such devices is even more challenging. The limits of measurement equipment, especially for the current measurement, are reached due to the fast rise and fall times. Ideal characterization requires a non-invasive, infinite bandwidth current sensor. This paper presents a galvanically isolated current sensor that combines magnetic field sensors and a printed circuit board integrated Rogowski coil. The insertion inductance of the hybrid current sensor is compared to a commercial coaxial shunt and a low inductance SMD shunt approach. The influence of the different current measurement devices on the switching loss characterization is investigated.}, author = {Ziegler, Philipp and Linzmaier, Jan and Haarer, Jörg and Marx, Philipp and Eckstein, Mattea and Roth-Stielow, Jörg}, booktitle = {2023 11th International Conference on Power Electronics and ECCE Asia (ICPE 2023 - ECCE Asia)}, issn = {2150-6086}, month = {05}, pages = {1181-1188}, title = {Wide Bandwidth Current Sensors and the Influence on the Switching Loss Characterization}, url = {https://ieeexplore.ieee.org/document/10213817}, year = 2023 }
  Link
  https://ieeexplore.ieee.org/document/10213817
2. Ziegler, P., Bura, M., Haarer, J., Marx, P., Hirning, D., Roth-Stielow, J.: Signal Processing Design for Wide Bandwidth Hybrid Current Sensor based on Enhanced Analog Operational Amplifier Circuit. 2023, IEEJ Journal of Industry Applications. Volume 12 Pages, 635–642 (2023).
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  @article{ziegler2023signal, abstract = {Hybrid current sensors are suitable for wide bandwidth current measurement. They entail the fusion of two different measurement circuits, one for DC and low-frequency current and another for high-frequency current. Thus, the advantages of the different measurement principles are incorporated in one current sensor. Hybrid current sensors generate output signals through a superposition of the signals from the low-frequency and high-frequency current sensors. This is realized using analog signal processing by means of an analog operational amplifier circuit. Realization of the superposition of the frequency responses of the different measurement circuits to achieve a constant gain in the transition area is challenging. This study focused on the analog signal processing and its enhancement. Specifically, two possible signal processing approaches to increase the bandwidth based on the state-of-the-art realization of a low-pass filter were devised. These approaches were investigated using a simulation model. Frequency response measurements using a hybrid current sensor based on tunneling magnetoresistance sensors and a Rogowski coil were used for verification. The results show that by enhancing the signal processing, the bandwidth of the current sensors can be significantly increased.}, author = {Ziegler, Philipp and Bura, Michael and Haarer, Jörg and Marx, Philipp and Hirning, David and Roth-Stielow, Jörg}, journal = {2023, IEEJ Journal of Industry Applications}, number = {Issue 4}, pages = {635-642}, title = {Signal Processing Design for Wide Bandwidth Hybrid Current Sensor based on Enhanced Analog Operational Amplifier Circuit}, url = {https://www.jstage.jst.go.jp/article/ieejjia/12/4/12_22007463/_article}, volume = {Volume 12 Pages }, year = 2023 }
  Link
  https://www.jstage.jst.go.jp/article/ieejjia/12/4/12_22007463/_article
3. Ziegler, P., Haarer, J., Marx, P., Eckstein, M., Haspel, A., Roth-Stielow, J.: Evaluation of a Low-Cost Wide Bandwidth Current Shunt for Characterization of Wide Bandgap Semiconductor Devices. In: 2023 25th European Conference on Power Electronics and Applications (EPE’23 ECCE Europe). pp. 1–9 (2023).
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  @inproceedings{10264595, abstract = {Characterizing the switching losses of wide bandgap semiconductor devices requires wide bandwidth measurement equipment with the smallest possible insertion inductance added to the commutation path by the current sensor. A common current measurement approach is using low-cost off-the-shelf SMD resistors and measure the voltage drop. This SMD shunt approach has a limited bandwidth due to parasitic inductances. In this work, an evaluation of such a low-cost current shunt is performed. The influences and constraints that limit the bandwidth are investigated. The design of a compensation network and the resulting bandwidth improvement are examined. Based on the theoretical discussion, a compact current shunt is designed, that allows a simple integration into the commutation path while adding a low insertion inductance. The measurement results show, that the common measurement approach can reach a bandwidth of several hundred MHz if the design constraints are met and can be further extended by a compensation network.}, author = {Ziegler, Philipp and Haarer, Jörg and Marx, Philipp and Eckstein, Mattea and Haspel, André and Roth-Stielow, Jörg}, booktitle = {2023 25th European Conference on Power Electronics and Applications (EPE'23 ECCE Europe)}, month = {09}, pages = {1-9}, title = {Evaluation of a Low-Cost Wide Bandwidth Current Shunt for Characterization of Wide Bandgap Semiconductor Devices}, url = {https://ieeexplore.ieee.org/document/10264595}, year = 2023 }
  Link
  https://ieeexplore.ieee.org/document/10264595
4. Ziegler, P., Al-Hussainy, A., Haarer, J., Marx, P., Roth-Stielow, J.: Design of a 2 kA Pulsed Current Source for Characterization of Current Sensors. In: PCIM Europe 2023; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. pp. 1–8 (2023).
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  @inproceedings{10173269, abstract = {This paper presents the design of a 2 kA pulsed current source. It uses parallel connected silicon carbid semiconductor devices to provide high current amplitudes and short rise and fall times. Also a custom gate driver, based on a galium nitride half-bridge, is used to allow short turn on and off times of the parallel connected semiconductor devices. In this way, current pulses with amplitudes up to 2 kA and rise and fall times of less than 60 ns can be generated by the current source, which are typical of today’s commutation current in power electronic systems.Therefore, it can be used for the characterization and comparison of highly dynamic current sensors.}, author = {Ziegler, Philipp and Al-Hussainy, Abbas and Haarer, Joerg and Marx, Philipp and Roth-Stielow, Joerg}, booktitle = {PCIM Europe 2023; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management}, month = {05}, pages = {1-8}, title = {Design of a 2 kA Pulsed Current Source for Characterization of Current Sensors}, url = {https://ieeexplore.ieee.org/document/10173269}, year = 2023 }
  Link
  https://ieeexplore.ieee.org/document/10173269
5. Ziegler, P., Zhao, Y., Haarer, J., Ruthardt, J., Fischer, M., Roth-Stielow, J.: Compact Design of a Wide Bandwidth High Current Sensor Using Tilted Magnetic Field Sensors. IEEE Transactions on Industry Applications. 1–10 (2023).
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  @article{10223415, abstract = {Magnetic field-based current sensors are widely used due to their galvanically insulated measurement principle. A well-proven concept is based on the discrete realization of Ampèere's law using a circular array of magnetic field sensors. Depending on the linear operating range of the magnetic field sensors, the radius of the circular array has to be chosen, leading to large dimensions for high current values. This paper presents a novel approach to build a compact wide bandwidth current sensor based on the combination of tilted tunnel-magnetoresistance sensors and a Rogowski coil. The used tunnel-magnetoresistance sensors are characterized and show an increased linear range in the current sensor application if they are tilted. In addition, the sensor sensitivity is varied with the tilt angle. A novel current sensor concept based on tilting in combination with repositioning the magnetic field sensors is presented. This concept offers the opportunity to reduce the size of state-of-the-art current sensors based on magnetic field sensors significantly. The proposed concept is verified in a current sensor prototype. The DC current linearity, the dynamic behavior as well as the signal-to-noise ratio is characterized. Ideas how this concept can be used and further developed are presented.}, author = {Ziegler, Philipp and Zhao, Yiru and Haarer, Jörg and Ruthardt, Johannes and Fischer, Manuel and Roth-Stielow, Jörg}, issn = {1939-9367}, journal = {IEEE Transactions on Industry Applications}, pages = {1-10}, title = {Compact Design of a Wide Bandwidth High Current Sensor Using Tilted Magnetic Field Sensors}, url = {https://ieeexplore.ieee.org/document/10223415}, year = 2023 }
  Link
  https://ieeexplore.ieee.org/document/10223415
2022
1. Marx, P., Assenheimer, J., Ziegler, P., Haarer, J., Roth-Stielow, J.: Reduction of Common Mode Disturbances in Parallel Modules of Integrated Modular Motor Drives. In: IEEE (ed.) 2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia). pp. 595–600 (2022).
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  @inproceedings{9806860, abstract = {Decreasing switching transition times and miniaturizing power electronic designs lead to higher electromagnetic disturbances. By synchronizing opposed switching transitions, common mode disturbances can be reduced without additional filters. This paper presents an approach to synchronize the switching transitions in parallel modules of integrated modular motor drives. Based on examinations on the parasitic impedances, switching transitions are synchronized in a proper way to ensure best results. Furthermore, the timing of the switching commands is adjusted to compensate differences in the propagation delay. The approach is validated by measurements on a test setup.}, author = {Marx, Philipp and Assenheimer, Jan and Ziegler, Philipp and Haarer, Jörg and Roth-Stielow, Jörg}, booktitle = {2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)}, editor = {IEEE}, isbn = {978-4-8868-6425-3}, month = {05}, pages = {595-600}, title = {Reduction of Common Mode Disturbances in Parallel Modules of Integrated Modular Motor Drives}, url = {https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9806860}, year = 2022 }
  Link
  https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9806860
2. Ziegler, P., Bura, M., Haarer, J., Marx, P., Hirning, D., Roth-Stielow, J.: Optimization Approaches for the Signal Processing of Hybrid Current Sensors. In: IEEE (ed.) 2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia). pp. 506–513 (2022).
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  @inproceedings{9807001, abstract = {Hybrid current sensors are suitable devices for wide bandwidth current measurement. They combine two different measurement circuits, one for DC and low-frequency current measurement and another for high frequency current measurement. This combines the advantages of different measurement principles in one current sensor. The output signal of the hybrid current sensor is generated through a superposition of the low-frequency and high-frequency current sensor. This is realized using analog signal processing by means of an analog operational amplifier circuit. The challenge is to superpose the frequency responses of the different measurement circuits achieving a constant gain in the transition area. This paper focuses on the analog signal processing and its optimization. Based on a state-of-the-art realization, two possible optimization approaches of the signal processing are presented to increase the bandwidth. These optimization approaches are investigated in a simulation model and verified by frequency response measurements of a hybrid current sensor based on tunneling magnetoresistance sensors and a Rogowski coil.}, author = {Ziegler, Philipp and Bura, Michael and Haarer, Jörg and Marx, Philipp and Hirning, David and Roth-Stielow, Jörg}, booktitle = {2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)}, editor = {IEEE}, month = {05}, pages = {506-513}, title = {Optimization Approaches for the Signal Processing of Hybrid Current Sensors}, url = {https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9807001}, year = 2022 }
  Link
  https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9807001
3. Hirning, D., Bauer, L., Ruthardt, J., Haarer, J., Ziegler, P., Roth-Stielow, J.: Online Junction Temperature Measurement of SiC-MOSFETs via Gate Impedance Using the Gate-Signal Injection Method. In: IEEE (ed.) 2022 24th European Conference on Power Electronics and Applications (EPE’22 ECCE Europe). pp. 1–9 (2022).
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  @inproceedings{9907316, abstract = {This paper presents a method for junction temperature monitoring of SiC-MOSFETs based on a high-frequency gate-signal injection. The signal is injected during steady state (e.g. off-state) resulting in a current response, which depends on the temperature dependent gate impedance. The external gate resistor is used as a current shunt to capture the current response. The resulting signal contains the junction temperature information due to the temperature dependency of the gate impedance. This paper focuses on a sinusoidal approach to overcome the challenges due to the temperature dependent parasitic capacitance of the gate circuit. Measurements show the proof of concept, however, there are still challenges to face.}, author = {Hirning, David and Bauer, Luca and Ruthardt, Johannes and Haarer, Jörg and Ziegler, Philipp and Roth-Stielow, Jörg}, booktitle = {2022 24th European Conference on Power Electronics and Applications (EPE'22 ECCE Europe)}, editor = {IEEE}, isbn = {978-9-0758-1539-9}, month = {09}, pages = {1-9}, title = {Online Junction Temperature Measurement of SiC-MOSFETs via Gate Impedance Using the Gate-Signal Injection Method}, url = {https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9907316}, year = 2022 }
  Link
  https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9907316
4. Marx, P., Seybold, F., Ziegler, P., Hirning, D., Roth-Stielow, J.: Investigations on the Active Reduction of Common Mode Noise with Opposing Noise Sources. In: 2022 24th European Conference on Power Electronics and Applications (EPE’22 ECCE Europe). pp. 1–9. IEEE (2022).
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  @inproceedings{9907509, abstract = {Conventional filters needed for the electromagnetic compatibility lower the system power density by consuming additional space in power electronic setups. To increase the power density, alternatives for these filters are needed. If the power electronic setup offers the possibility to synchronize two opposing switching transitions, the common mode noise can be reduced without additional filters. In this case two opposing noise currents reduce one another by superimposition. For power electronic setups which do not offer the possibility to synchronize switching transitions, this paper presents an approach which uses additional half bridges as opposing noise sources connected to a replicated grounding impedance to create the opposing common mode noise. The main goal of the opposing noise source is to create similar potential changes as the power electronic setup over the replicated grounding impedance. The replicated grounding impedance emulates the grounding impedance of an ohmic inductive load with discrete elements. The achieved reduction of the common mode noise with this approach is evaluated with measurements.}, author = {Marx, Philipp and Seybold, Felix and Ziegler, Philipp and Hirning, David and Roth-Stielow, Jörg}, booktitle = {2022 24th European Conference on Power Electronics and Applications (EPE'22 ECCE Europe)}, isbn = {978-9-0758-1539-9}, month = {09}, pages = {1-9}, publisher = {IEEE}, title = {Investigations on the Active Reduction of Common Mode Noise with Opposing Noise Sources}, url = {https://ieeexplore.ieee.org/document/9907509}, year = 2022 }
  Link
  https://ieeexplore.ieee.org/document/9907509
5. Ziegler, P., Festerling, T., Haarer, J., Marx, P., Hirning, D., Roth-Stielow, J.: Influences of Parasitic Capacitances in Wide Bandwidth Rogowski Coils for Commutation Current Measurement. In: IEEE (ed.) 2022 24th European Conference on Power Electronics and Applications (EPE’22 ECCE Europe). pp. 1–10 (2022).
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  @inproceedings{9907377, abstract = {This paper focuses on the capacitive coupling of PCB integrated Rogowski coils for commutation current measurement. It investigates the cause and the influence of parasitic capacitances on the measurement signal. It discusses the advantages of a differential winding arrangement and the reasons why shielding is not an option in this application. The parasitic capacitance of three different winding arrangements are measured and compared to a Rogowski coil approach with minimized parasitic capacitance. On the base of sensor prototypes, the influence on the measurement is investigated in a pulsed current source.}, author = {Ziegler, Philipp and Festerling, Tobias and Haarer, Jorg and Marx, Philipp and Hirning, David and Roth-Stielow, Jorg}, booktitle = {2022 24th European Conference on Power Electronics and Applications (EPE'22 ECCE Europe)}, editor = {IEEE}, isbn = {978-9-0758-1539-9}, month = {09}, pages = {1-10}, title = {Influences of Parasitic Capacitances in Wide Bandwidth Rogowski Coils for Commutation Current Measurement}, url = {https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9907377}, year = 2022 }
  Link
  https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9907377
2021
1. Ziegler, P., Stjepandic, F., Ruthardt, J., Marx, P., Fischer, M., Roth-Stielow, J.: Wide Bandwidth Current Sensor for Characterization of High Current Power Semiconductor Modules. In: 2021 23rd European Conference on Power Electronics and Applications (EPE’21 ECCE Europe). pp. 1–9 (2021).
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  @inproceedings{9570438, abstract = {This paper presents a current sensor for commutation current measurement of high current power semiconductor modules with a bandwidth from DC up to 240 MHz. It is integrated in the commutation path with a coaxial housing generating a specified measurement point adding a low insertion inductance of 1.8 nH. It consists of tunnel-magnetoresistance sensors for low frequency current measurement and a PCB integrated Rogowski coil for high frequency current measurement. The measurement techniques are combined using the HOKA principle. The DC current linearity, the dynamic behavior as well as the signal-to-noise ratio of the current sensor is characterized.}, author = {Ziegler, Philipp and Stjepandic, Franjo and Ruthardt, Johannes and Marx, Philipp and Fischer, Manuel and Roth-Stielow, Jörg}, booktitle = {2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe)}, month = {09}, pages = {1-9}, title = {Wide Bandwidth Current Sensor for Characterization of High Current Power Semiconductor Modules}, url = {https://ieeexplore.ieee.org/document/9570438}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9570438
2. Ruthardt, J., Klinkhammer, A., Marx, P., Ziegler, P., Nitzsche, M., Sharma, K., Roth-Stielow, J.: Lifetime Extension of Power Semiconductor Devices by Closed-Loop Junction Temperature Control. In: 2021 23rd European Conference on Power Electronics and Applications (EPE’21 ECCE Europe). pp. 1–10 (2021).
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  @inproceedings{ruthardt2021lifetime, abstract = {The lifetime of power semiconductor devices is mainly affected by the thermal stress they are exposed to. Especially temperature swings damage these devices due to different coefficients of thermal expansion of the material layers inside the device. This leads to mechanical strain between these layers. This paper proposes a closed loop junction temperature control system, which is able to reduce occurring temperature swings in order to reduce the damage and to extend the expected lifetime. An online junction temperature measurement is required in order to obtain information about the real-time temperature. This is realized by measuring the temperature sensitive on-resistance of the used MOSFET. Then, the junction temperature is estimated with a calibration curve. Another requirement is the possibility to influence the junction temperature during operation. Therefore, the switching frequency is varied to affect the switching losses. This influences the junction temperature. In addition, a set-value generator is presented, which generates suitable set values to reduce temperature swings.}, author = {Ruthardt, Johannes and Klinkhammer, Arvid and Marx, Philipp and Ziegler, Philipp and Nitzsche, Maximilian and Sharma, Kanuj and Roth-Stielow, Jörg}, booktitle = {2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe)}, isbn = {978-9-0758-1537-5}, month = {09}, pages = {1-10}, title = {Lifetime Extension of Power Semiconductor Devices by Closed-Loop Junction Temperature Control}, url = {https://ieeexplore.ieee.org/document/9570681}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9570681
3. Ruthardt, J., Hirning, D., Sharma, K., Nitzsche, M., Ziegler, P., Fischer, M., Roth-Stielow, J.: Investigations on Online Junction Temperature Measurement for SiC-MOSFETs Using the Gate-Signal Injection Method. In: 2021 IEEE Energy Conversion Congress and Exposition (ECCE). pp. 5354–5359 (2021). https://doi.org/10.1109/ECCE47101.2021.9595166.
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  @inproceedings{9595166, abstract = {This paper presents investigations on the suitability of using the gate-signal injection method for junction temperature measurement of SiC-MOSFETs. The method is based on the temperature sensitivity of the internal gate resistance. A high frequency signal is injected into the gate circuit while the MOSFET is operating. The response of the injected signal is a high frequency current, which depends on the temperature sensitive gate circuit’s impedance. This current causes a voltage drop across the external gate resistor. This voltage depends on the junction temperature and is evaluated. This method was successfully implemented on Si-IGBTs in the past. However, there are challenges to face in implementing this method on SiC-MOSFETs. This paper shows the challenges and proposes solutions to overcome them.}, author = {Ruthardt, Johannes and Hirning, David and Sharma, Kanuj and Nitzsche, Maximilian and Ziegler, Philipp and Fischer, Manuel and Roth-Stielow, Jörg}, booktitle = {2021 IEEE Energy Conversion Congress and Exposition (ECCE)}, doi = {10.1109/ECCE47101.2021.9595166}, issn = {2329-3748}, month = {10}, pages = {5354-5359}, title = {Investigations on Online Junction Temperature Measurement for SiC-MOSFETs Using the Gate-Signal Injection Method}, url = {https://ieeexplore.ieee.org/document/9595166}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9595166
4. Nitzsche, M., Ziegler, P., Michelberger, A., Barón, K.M., Ruthardt, J., Roth-Stielow, J.: Dynamic Thermal Design of an Active Power Cycling Test Bench for SiC MOSFETs. In: 2021 23rd European Conference on Power Electronics and Applications (EPE’21 ECCE Europe). pp. 1–7 (2021).
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  @inproceedings{9570564, abstract = {This paper presents an active power cycling approach whereby the inputs and outputs of two three-phase inverters are coupled in order to achieve circular energy flow. Focus is put on the thermal design of the test setup which concentrates on achieving short thermal cycles and high temperature dynamic for accelerated lifetime tests of SiC MOSFETs. These goals are achieved by the application of custom 3D-printed aluminum heat sinks and by using non-constant flow of the cooling medium.}, author = {Nitzsche, Maximilian and Ziegler, Philipp and Michelberger, Andre and Barón, Kevin Muñoz and Ruthardt, Johannes and Roth-Stielow, Jörg}, booktitle = {2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe)}, month = {09}, pages = {1-7}, title = {Dynamic Thermal Design of an Active Power Cycling Test Bench for SiC MOSFETs}, url = {https://ieeexplore.ieee.org/document/9570564}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9570564
5. Koch, D., Bantle, H., Acuna, J., Ziegler, P., Kallfass, I.: Design Methodology for Ultra-Compact Rogowski Coils for Current Sensing in Low-Voltage High-Current GaN Based DC/DC-Converters. In: 2021 23rd European Conference on Power Electronics and Applications (EPE’21 ECCE Europe). p. P.1-P.9 (2021).
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  @inproceedings{9570596, abstract = {This paper presents a design methodology, verified by measurements, of a differential Rogowski coil based compact, high bandwidth (> 500 MHz) PCB embedded current sensor for minimal invasive sensing (insertion inductance ≈ 200 pH) of transistor and phase currents in 48 V mild-hybrid Gallium Nitride based DC/DC-converters with paralleled transistors for high output currents. Two different sensor concepts with and without a planar shield are described and investigated. More than 30 designs with different winding number, structure and pitch are analyzed in 3D-finite element simulations. Finally, a standalone Rogowski-coil sensor for transistor current and a combination of a magnetoresistance sensor and a Rogowski-coil for phase output current measurements are presented.}, author = {Koch, Dominik and Bantle, Hannes and Acuna, Javier and Ziegler, Philipp and Kallfass, Ingmar}, booktitle = {2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe)}, isbn = {978-9-0758-1537-5}, month = {09}, pages = {P.1-P.9}, title = {Design Methodology for Ultra-Compact Rogowski Coils for Current Sensing in Low-Voltage High-Current GaN Based DC/DC-Converters}, url = {https://ieeexplore.ieee.org/document/9570596}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9570596
6. Fischer, M., Hu, Y., Ruthardt, J., Ziegler, P., Haarer, J., Roth-Stielow, J.: Comparison of an Interleaved Multi-Branch Inverter and a Four-Level Inverter with Variable Voltage Levels for Emulation of Three-Phase Machines. In: 2021 IEEE Energy Conversion Congress and Exposition (ECCE). pp. 2570–2575 (2021). https://doi.org/10.1109/ECCE47101.2021.9595668.
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  @inproceedings{9595668, abstract = {Power-hardware-in-the-loop emulation of electrical machines is a useful tool to simplify the development and testing process of traction inverters and their control systems at different operating conditions. This requires two fundamental components: a real-time operating machine model and an applicable power electronic device, which adjusts the same currents and voltages as the surveyed machine would. This paper compares two different power electronic topologies regarding their suitability for emulation of three-phase machines. The surveyed topologies are on the one hand a multi-branch interleaved-switched inverter, which is a state-of-the-art solution and also used in commercial machine emulators. On the other hand, a four-level inverter topology with variable voltage levels is analyzed, which is custom-built for the purpose of emulating three-phase machines. Within this paper the setup of both topologies as well as the comparative analysis by measurement results are presented.}, author = {Fischer, Manuel and Hu, Yang and Ruthardt, Johannes and Ziegler, Philipp and Haarer, Jörg and Roth-Stielow, Jörg}, booktitle = {2021 IEEE Energy Conversion Congress and Exposition (ECCE)}, doi = {10.1109/ECCE47101.2021.9595668}, issn = {2329-3748}, month = {10}, pages = {2570-2575}, title = {Comparison of an Interleaved Multi-Branch Inverter and a Four-Level Inverter with Variable Voltage Levels for Emulation of Three-Phase Machines}, url = {https://ieeexplore.ieee.org/document/9595668}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9595668
7. Ziegler, P., Zhao, Y., Haarer, J., Ruthardt, J., Fischer, M., Roth-Stielow, J.: Compact Design of a Wide Bandwidth High Current Sensor Using Tilted Magnetic Field Sensors. In: 2021 IEEE Energy Conversion Congress and Exposition (ECCE). pp. 5528–5534 (2021). https://doi.org/10.1109/ECCE47101.2021.9595039.
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  @inproceedings{9595039, abstract = {Magnetic field-based current sensors are widely used due to their galvanically isolated measurement principle. A well-proved concept is based on the discrete realization of the Ampère´s law using a circular array of magnetic field sensors. Depending on the linear operating range of the magnetic field sensors the radius of the circular array has to be chosen, leading to large dimensions for high current values. This paper presents a novel approach to build a compact wide bandwidth current sensor based on the combination of tilted tunnel-magnetoresistance sensors and a Rogowski coil. The used tunnel-magnetoresistance sensors are characterized and show an increased linear range in the a current sensor application if they are tilted. In addition, the sensor sensitivity is varied with the tilt angel. A novel current sensor concept based on tilting in combination with repositioning the magnetic field sensors is presented. This concept offers the opportunity to reduce the size of state-of-the-art current sensors based on magnetic field sensors significantly. The proposed concept is verified in a current sensor prototype and the DC current linearity, the dynamic behavior as well as the signal-to-noise ratio is characterized.}, author = {Ziegler, Philipp and Zhao, Yiru and Haarer, Jörg and Ruthardt, Johannes and Fischer, Manuel and Roth-Stielow, Jörg}, booktitle = {2021 IEEE Energy Conversion Congress and Exposition (ECCE)}, doi = {10.1109/ECCE47101.2021.9595039}, issn = {2329-3748}, month = {10}, pages = {5528-5534}, title = {Compact Design of a Wide Bandwidth High Current Sensor Using Tilted Magnetic Field Sensors}, url = {https://ieeexplore.ieee.org/document/9595039}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9595039
8. Marx, P., Assenheimer, J., Ruthardt, J., Ziegler, P., Nitzsche, M., Fischer, M., Roth-Stielow, J.: Common Mode Voltage Cancellation in Integrated Modular Motor Drives. In: 2021 23rd European Conference on Power Electronics and Applications (EPE’21 ECCE Europe). p. P.1-P.9 (2021).
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  @inproceedings{9570411, abstract = {Increasing switching transition slopes and miniaturizing of power electronic set-ups lead to more problems due to electromagnetic interference (EMI). This paper presents a concept to suppress the electromagnetic disturbances in modular electrical drives without using common mode filters. The usage of full bridge converters enables the synchronization of the switching transitions to suppress the emitted common mode disturbances of every single module. To evaluate the concept, the parasitic paths of a single module are investigated. With consideration of the parasitic paths, an accurate EMI model is built which identifies improvements for the cancellation concept in future applications. Finally, the concept and the simulation model are verified by measurements.}, author = {Marx, Philipp and Assenheimer, Jan and Ruthardt, Johannes and Ziegler, Philipp and Nitzsche, Maximilian and Fischer, Manuel and Roth-Stielow, Jörg}, booktitle = {2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe)}, month = {09}, pages = {P.1-P.9}, title = {Common Mode Voltage Cancellation in Integrated Modular Motor Drives}, url = {https://ieeexplore.ieee.org/document/9570411}, year = 2021 }
  Link
  https://ieeexplore.ieee.org/document/9570411
2020
1. Ziegler, P., Tröster, N., Schmidt, D., Ruthardt, J., Fischer, M., Roth-Stielow, J.: Wide Bandwidth Current Sensor for Commutation Current Measurement in Fast Switching Power Electronics. In: 2020 22nd European Conference on Power Electronics and Applications (EPE’20 ECCE Europe). p. P.1-P.9 (2020).
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  @inproceedings{9215686, abstract = {This paper presents a current sensor for commutation current measurement with a bandwidth from DC up to 315 MHz. The sensor is inserted in the commutation loop by a coaxial housing with a low insertion inductance of about 1.2 nH. The sensor is based on the HOKA principle using tunnel magnetoresistance sensors and a Rogowski-coil for low and high frequency current measurement respectively. The current sensor is tested in a half-bridge configuration equipped with gallium nitride transistors and compared to two state-of-the-art current sensors.}, author = {{Ziegler}, P. and {Tröster}, N. and {Schmidt}, D. and {Ruthardt}, J. and {Fischer}, M. and {Roth-Stielow}, J.}, booktitle = {2020 22nd European Conference on Power Electronics and Applications (EPE'20 ECCE Europe)}, month = {09}, pages = {P.1-P.9}, title = {Wide Bandwidth Current Sensor for Commutation Current Measurement in Fast Switching Power Electronics}, url = {https://ieeexplore.ieee.org/document/9215686}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9215686
2. Ruthardt, J., Sharma, K., Schmid, T., Nitzsche, M., Ziegler, P., Roth-Stielow, J.: Online Junction Temperature Measurement of Power Semiconductor Devices. In: PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. pp. 1–5 (2020).
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  @inproceedings{9178170, abstract = {Monitoring the junction temperature of power electronic devices enables over-temperature protection, health monitoring, online lifetime estimation or junction temperature control to extend the expected lifetime. A method for online junction temperature estimation in power semiconductor devices based on the temperature sensitive reverse-recovery behavior of pin-diodes is presented in this paper. Since the reverse-recovery time of diodes is a function of their junction temperature, it can be used for junction temperature measurement. Therefore, a simple measurement circuit is developed to determine the duration between the start of the load current commutation and the instant of time when the diode is in blocking mode. This duration, which is related to the reverse-recovery-time, is defined as the quasi-reverse-recovery time.}, author = {{Ruthardt}, J. and {Sharma}, K. and {Schmid}, T. and {Nitzsche}, M. and {Ziegler}, P. and {Roth-Stielow}, J.}, booktitle = {PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management}, month = {07}, pages = {1-5}, title = {Online Junction Temperature Measurement of Power Semiconductor Devices}, url = {https://ieeexplore.ieee.org/document/9178170}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9178170
3. Ruthardt, J., Schulte, H., Ziegler, P., Fischer, M., Nitzsche, M., Roth-Stielow, J.: Junction Temperature Control Strategy for Lifetime Extension of Power Semiconductor Devices. In: 2020 22nd European Conference on Power Electronics and Applications (EPE’20 ECCE Europe). pp. 1–9 (2020).
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  BibTeX
  @inproceedings{9215718, abstract = {The lifetime of power semiconductor devices mainly depends on their thermal stress. In particular, temperature swings cause damage due to different coefficients of thermal expansion of the different materials, which are used in power semiconductor devices. These temperature swings occur when the environmental temperature or the load conditions and with them the power losses change. Junction temperature controllers are able to extend the expected lifetime by reducing the occurring temperature swings. This paper proposes two control strategies to calculate a suitable set value for junction temperature controllers, which leads to a smoother temperature course with fewer swings. Both strategies do not affect the normal operation by for example limiting the output parameters. They affect the efficiency of the power electronic circuit to influence the power losses and thermal conditions.}, author = {{Ruthardt}, J. and {Schulte}, H. and {Ziegler}, P. and {Fischer}, M. and {Nitzsche}, M. and {Roth-Stielow}, J.}, booktitle = {2020 22nd European Conference on Power Electronics and Applications (EPE'20 ECCE Europe)}, month = {09}, pages = {1-9}, title = {Junction Temperature Control Strategy for Lifetime Extension of Power Semiconductor Devices}, url = {https://ieeexplore.ieee.org/document/9215718}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9215718
4. Fischer, M., Ruthardt, J., Ketchedjian, V., Ziegler, P., Nitzsche, M., Roth-Stielow, J.: Four-Level Inverter with Variable Voltage Levels for Hardware-in-the-Loop Emulation of Three-Phase Machines. In: 2020 22nd European Conference on Power Electronics and Applications (EPE’20 ECCE Europe). p. P.1-P.8 (2020).
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  BibTeX
  @inproceedings{9215767, abstract = {In order to emulate the behavior of three-phase machines in a hardware-in-the-loop test bench, an applicable power electronic device is required. For this purpose, an inverter concept with four variable voltage levels per phase is presented. This concept precisely fulfills the requirements of three-phase machine emulation. The presented inverter is theoretically able to adjust the ideal countervoltage course which is needed to emulate three-phase machines' electrical behavior. In contrast, the countervoltages of commonly used power electronic devices suffer from deviation caused by switched-mode operation or limited bandwidth. Within this paper the setup of the four-level inverter is presented. Besides, the paper discusses a control strategy for operating the four-level inverter as a three-phase machine emulator.}, author = {{Fischer}, M. and {Ruthardt}, J. and {Ketchedjian}, V. and {Ziegler}, P. and {Nitzsche}, M. and {Roth-Stielow}, J.}, booktitle = {2020 22nd European Conference on Power Electronics and Applications (EPE'20 ECCE Europe)}, month = {09}, pages = {P.1-P.8}, title = {Four-Level Inverter with Variable Voltage Levels for Hardware-in-the-Loop Emulation of Three-Phase Machines}, url = {https://ieeexplore.ieee.org/document/9215767}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9215767
5. Nitzsche, M., Barón, K.M., Ziegler, P., Wagner, F., Roth-Stielow, J.: Dynamic AC Power Cycling with Coupled Inverters Operating Under Application-Oriented Conditions. In: VDE (ed.) CIPS 2020; 11th International Conference on Integrated Power Electronics Systems. pp. 576–581. , Berlin, Germany (2020).
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  @inproceedings{9097745, abstract = {In order to determine the reliability of power semiconductor devices, power cycling tests are applied. Most commonly the necessary heat is generated by conduction losses in the die. As this does not reflect the loss generation in the application, this paper presents a new approach. The heat is generated by a combination of switching and conduction losses exactly as in the application. The inputs and outputs of two three-phase inverters are coupled in order to achieve circular energy flow and therefore high efficiency of the power cycling test. Furthermore, a novel 3D-printed aluminum module heat sink is designed and utilized to achieve the highest possible temperature dynamic.}, address = {Berlin, Germany}, author = {Nitzsche, Maximilian and Barón, Kevin Muñoz and Ziegler, Philipp and Wagner, Felix and Roth-Stielow, Jörg}, booktitle = {CIPS 2020; 11th International Conference on Integrated Power Electronics Systems}, editor = {VDE}, language = {English}, month = {03}, pages = {576-581}, title = {Dynamic AC Power Cycling with Coupled Inverters Operating Under Application-Oriented Conditions}, url = {https://ieeexplore.ieee.org/document/9097745}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9097745
6. Fischer, M., Erthle, D., Ziegler, P., Ruthardt, J., Roth-Stielow, J.: Comparison of Two Power Electronic Topologies for Power Hardware in the Loop Machine Emulator. In: 2020 IEEE Applied Power Electronics Conference and Exposition (APEC). pp. 2950–2954. , New Orleans, USA, (2020).
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  @inproceedings{9124094, abstract = {Emulating electrical machines simplifies development and testing inverters and their control systems in different operating conditions. Therefore, two fundamental components are required: a real-time operating machine model and an applicable power electronic device, which adjusts the same currents and voltages as the surveyed machine would. Within this paper, two different power electronic topologies are compared regarding their suitability for hardware in the loop machine emulation. The surveyed topologies are a multibranch interleaved-switched inverter on the one hand and an inverter with output filter on the other hand. Especially their dynamic behavior in emulating the machine currents’ course as precise as possible is investigated. Moreover, additional disturbances caused by the power electronics’ switched-mode operation are analyzed, too. For this purpose, both power electronic devices are set up in hardware, controlled by an exemplary machine model. This paper presents the setup of the two topologies and the dedicated control system as well as the analysis by simulation and measurement.}, address = {New Orleans, USA,}, author = {Fischer, Manuel and Erthle, Dennis and Ziegler, Philipp and Ruthardt, Johannes and Roth-Stielow, Jörg}, booktitle = {2020 IEEE Applied Power Electronics Conference and Exposition (APEC)}, eventdate = {15-19. March 2020}, issn = {2470-6647}, month = {03}, pages = {2950-2954}, title = {Comparison of Two Power Electronic Topologies for Power Hardware in the Loop Machine Emulator}, url = {https://ieeexplore.ieee.org/document/9124094/}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9124094/
7. Ruthardt, J., Schnabel, L., Ziegler, P., Marx, P., Sharma, K., Fischer, M., Nitzsche, M., Roth-Stielow, J.: Closed Loop Junction Temperature Control of Power Transistors for Lifetime Extension. In: 2020 IEEE Applied Power Electronics Conference and Exposition (APEC). pp. 2955–2955. , New Orleans, USA, (2020).
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  BibTeX
  @inproceedings{9124000, abstract = {The lifetime of power transistors significantly depends on the junction temperature swings. These temperature swings occur, for instance when the load conditions of the power electronic circuit change. In this work, a closed loop junction temperature control system is designed to increase the expected lifetime of power transistors. Therefore, the control system reduces the occurring temperature swings by influencing the power losses of the power transistor. For that, the gate driver’s supply voltage is adjusted, which affects the switching speed and the conduction characteristics. The junction temperature is measured by determination of the temperature sensitive internal gate resistance via the high-frequency gate-signalinjection method and fed back to the junction temperature controller. Both, the junction temperature measurement method and the control system are evaluated with a three-phase two-level voltage-source inverter. It is extended by a control strategy, which calculates a suitable set value for the controller in order to reduce junction temperature swings.}, address = {New Orleans, USA,}, author = {Ruthardt, Johannes and Schnabel, Lukas and Ziegler, Philipp and Marx, Philipp and Sharma, Kanuj and Fischer, Manuel and Nitzsche, Maximilian and Roth-Stielow, Jörg}, booktitle = {2020 IEEE Applied Power Electronics Conference and Exposition (APEC)}, eventdate = {15-19. March 2020}, issn = {2470-6647}, month = {03}, pages = {2955-2955}, title = {Closed Loop Junction Temperature Control of Power Transistors for Lifetime Extension}, url = {https://ieeexplore.ieee.org/document/9124000/}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9124000/
8. Munoz Baron, K., Sharma, K., Nitzsche, M., Ziegler, P., Koch, D., Kallfass, I.: Characterization of Threshold Voltage for Application-Oriented Power Cycling Conditions for Wide-Bandgap Power Devices. In: PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. pp. 1–7 (2020).
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  @inproceedings{9178169, abstract = {A quasi-threshold voltage measurement setup is implemented in a test bench to allow online parameter observation during power cycling tests for silicon carbide MOSFETs. The threshold voltage is known to change during operation, either temporarily or non-reversibly, due to degradation and trapping phenomena in the MOS-structure. To evaluate different assembly and interconnection technologies, for conditions as close to the real application as possible, an application-oriented power cycling test setup is examined. The proposed test bench allows the measurement of a quasi-threshold voltage under the influence of different off-state drain-source and gate voltages. Measurements show a decrease of quasi-threshold voltage with increasing off-state drain-source voltage and negative gate-source voltage.}, author = {{Munoz Baron}, K. and {Sharma}, K. and {Nitzsche}, M. and {Ziegler}, P. and {Koch}, D. and {Kallfass}, I.}, booktitle = {PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management}, month = {07}, pages = {1-7}, title = {Characterization of Threshold Voltage for Application-Oriented Power Cycling Conditions for Wide-Bandgap Power Devices}, url = {https://ieeexplore.ieee.org/document/9178169}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9178169
9. Ziegler, P., Haarer, J., Ruthardt, J., Nitzsche, M., Roth-Stielow, J.: Air-Core Toroidal Transformer Concept for High-Frequency Power Converters. In: PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. pp. 1–5 (2020).
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  @inproceedings{9178236, abstract = {This paper presents an air-core toroidal transformer concept, which offers the ability to integrate the power electronic circuit of a converter into the transformer structure. Air-core magnetic components in high-frequency power converters give the advantage of no core losses. The transformer is designed with the help of a magnetic circuit model verified with a finite-element method simulation. The analytic and measured results of a prototype are compared.}, author = {{Ziegler}, P. and {Haarer}, J. and {Ruthardt}, J. and {Nitzsche}, M. and {Roth-Stielow}, J.}, booktitle = {PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management}, month = {07}, pages = {1-5}, title = {Air-Core Toroidal Transformer Concept for High-Frequency Power Converters}, url = {https://ieeexplore.ieee.org/document/9178236}, year = 2020 }
  Link
  https://ieeexplore.ieee.org/document/9178236
2019
1. Ruthardt, J., Ziegler, P., Fischer, M., Roth-Stielow, J.: Model Based Junction Temperature Control Using the Gate Driver Voltage as a Correction Variable. In: 2019 21st European Conference on Power Electronics and Applications (EPE ’19 ECCE Europe). p. P.1-P.8. , Genova, Italy (2019). https://doi.org/10.23919/EPE.2019.8915157.
  - BibTeX
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  BibTeX
  @inproceedings{8915157, abstract = {Junction temperature swings, caused by load alternation in power electronics, lead to a reduced lifetime of power semiconductor devices. When temperature swings occur, the different material layers of the power semiconductor device expand in a different way because of their different coefficient of thermal expansion. The result is mechanical strain between these layers. Junction temperature control systems are able to minimize the occurring temperature swings and to smooth the junction temperature course. Thus, the expected lifetime of the power semiconductor device is extended. A possibility to affect the junction temperature and the value of the junction temperature are required to realize such a control system. This paper proposes a model based junction temperature control system for lifetime extension of the power semiconductor devices using the gate driver's supply voltage as a correction variable. Therefore, the junction temperature is calculated by a thermal model with the load condition as an input variable.}, address = {Genova, Italy}, author = {Ruthardt, Johannes and Ziegler, Philipp and Fischer, Manuel and Roth-Stielow, Jörg}, booktitle = {2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe)}, doi = {10.23919/EPE.2019.8915157}, eventdate = {9/3/2019 - 9/5/2019}, language = {English}, month = {09}, pages = {P.1-P.8}, title = {Model Based Junction Temperature Control Using the Gate Driver Voltage as a Correction Variable}, url = {https://ieeexplore.ieee.org/document/8915157/}, year = 2019 }
  Link
  https://ieeexplore.ieee.org/document/8915157/
2. Fischer, M., Ruthardt, J., Nitzsche, M., Ziegler, P., Roth-Stielow, J.: Investigation on Carrier Signals to Minimize the Overall Current Ripple of an Interleaved-Switched Inverter. In: PCIM Europe 2019; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. pp. 1–6. VDE Verlag (2019).
  - BibTeX
  BibTeX
  @inproceedings{8767709, abstract = {This paper proposes a method to minimize the overall output current ripple of an interleaved-switched inverter with several half bridge branches per phase. Therefore, two types of temporal shift between the carrier signals of different branches and phases are defined. In order to get the smallest possible overall current ripple, a dynamic variation of these two temporal shifts is investigated.}, author = {Fischer, Manuel and Ruthardt, Johannes and Nitzsche, Maximilian and Ziegler, Philipp and Roth-Stielow, Jörg}, booktitle = {PCIM Europe 2019; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management}, eventdate = {7. - 9. Mai 2019}, isbn = {978-3-8007-4938-6}, language = {English}, month = {05}, pages = {1-6}, publisher = {VDE Verlag}, title = {Investigation on Carrier Signals to Minimize the Overall Current Ripple of an Interleaved-Switched Inverter}, year = 2019 }

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Philipp Ziegler, M.Sc.

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