Low Loss Voltage Equalization Scheme for Series-Connected BiMOSFETs for Pulsed Power Applications

Abstract

High-voltage solid state pulse modulators are designed to handle voltage levels, which are several times the order of individual device voltage ratings, necessitating series connection of switches. The main challenge in series connection is to ensure equal voltage across all the devices in the stack under steady state and transient conditions. This paper describes the circuit design for static and dynamic voltage equalization in series-connected high-voltage BiMOSFETs operating in the pulsed mode. A generalized expression for voltage equalization circuit parameters has been derived and standby protection is achieved by means of active clamping. The dynamic equalization circuit has low power loss and the designed system has the capability to withstand turn-on/turn-off failure of one or more devices. A prototype 4 kV series switch has been simulated in PSpice, built and tested under deliberate asynchronism and also by removing the gate pulse to the lower device in the stack. This work forms a part of high-voltage pulse modulator development at Pulsed High Power Microwave Division, Raja Ramanna Center for Advanced Technology, Indore.

Keywords:

• Active clamping
• BiMOSFET
• Dynamic equalization
• Series connection
• Static equalization
• Voltage balance

ACKNOWLEDGEMENTS

The authors would like to thank the Project Placement Committee of RRCAT, Shri. S. C. Joshi, Director, Proton Accelerator Group, Dr. P. A. Naik, Director, Raja Ramanna Centre for Advanced Technology, Dr. Sasangan Ramanathan, Dean, Amrita Vishwa Vidyapeetam, Dr. K. C. Sindhu Thampatty, Chairperson, Dept. of EEE, Amrita Vishwa Vidyapeetam and the staff of Amrita Vishwa Vidyapeetam for their support and encouragement. We also thank Mr. Vinod Phadnis for his technical assistance.

Additional information

Notes on contributors

M. Acharya

Mahesh Acharya received the BE in electrical engineering from Rajasthan University, Jaipur. He also received MTech in engineering physics from Homi Bhabha National Institute, RRCAT, Indore. He joined Raja Ramanna Centre for Advanced Technology in 2006. His research interests include pulsed power technology, solid state pulse modulators, RF engineering, power electronics and their applications in particle accelerators. He has authored several papers in various national and international journals.

V. Harini

Harini V received the BTech in electrical and electronics engineering from Jawaharlal Nehru Technological University, Hyderabad in 2016. She is currently pursuing her MTech degree in power electronics from Amrita Vishwa Vidyapeetham, Coimbatore. Email: [email protected]

T. Reghu

T Reghu was born in the southern province of India in 1968. He received associate membership of Institution of Engineers (India) in 1992 and MEngg in 2000. He joined Raja Ramanna Centre for Advanced Technology in 1987 and presently leads klystron modulator power supply activities. His research interests include pulsed power systems, power electronics, high power klystron modulators and their applications in particle accelerators. He has authored several papers in various national and international journals. Email: [email protected]

Purushottam Shrivastava

Purushottam Shrivastava received the BE in electronics and telecommunication from SGSITS, DAVV, Indore, MP, India, in 1985. He developed C and Ext C band solid state amplifiers for first Indian National Satellite INSAT II-A at Space Applications Centre, ISRO, Ahmedabad, India, during his initial career. He joined Raja Ramanna Centre for Advanced Technology, Department of Atomic Energy, RRCAT, Indore, MP, India in 1988. He is currently an outstanding scientist and head, Pulsed High Power Microwave Division of RRCAT. He also holds the responsibility as associate director, Proton Accelerator Group of RRCAT and project coordinator for International Collaboration in CERN accelerators. His research interests include indigenous design, development and commissioning of high power RF and microwave systems for various particle accelerators, advanced solid state pulse modulators for microwave tubes, commissioning and up-gradations of particle accelerators. He has more than 140 publications in national, international journals and conferences and over 354 citations. Email: [email protected]

A. Vijayakumari

Vijayakumari received BE and ME in electrical and electronics engineering Engineering from Bharathiar University, Coimbatore, India in 1991 and 2001, respectively, and PhD in electrical engineering from the Anna University in 2014. From 1995 to 1999 she was with Govt. College of Engineering, Coimbatore as a guest lecturer and in 2001 joined in Amrita School of Engineering, Coimbatore, Amrita Vishwa Vidyapeetha, as lecturer and presently serving as associate professor. Email: [email protected]