Design of High-Voltage Switch-Mode Power Amplifier Based on Digital-Controlled Hybrid Multilevel Converter

Compared with conventional Class-A, Class-B, and Class-AB amplifiers, Class-D amplifier, also known as switching amplifier, employs pulse width modulation (PWM) technology and solid-state switching devices, capable of achieving much higher efficiency. However, PWM-based switching amplifier is usually designed for low-voltage application, offering a maximum output voltage of several hundred Volts. Therefore, a step-up transformer is indispensably adopted in PWM-based Class-D amplifier to produce high-voltage output. In this paper, a switching amplifier without step-up transformer is developed based on digital pulse step modulation (PSM) and hybrid multilevel converter. Under the control of input signal, cascaded power converters with separate DC sources operate in PSM switch mode to directly generate high-voltage and high-power output. The relevant topological structure, operating principle, and design scheme are introduced. Finally, a prototype system is built, which can provide power up to 1400 Watts and peak voltage up to ±1700 Volts. And the performance, including efficiency, linearity, and distortion, is evaluated by experimental tests.

[1]  Manuel Moreno-Eguilaz,et al.  Clamping diode caused distortion in multilevel NPC Full-Bridge audio power amplifiers , 2012, IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society.

[2]  Xueqiang Zhang,et al.  IGBT series connection under Active Voltage Control with temporary clamp , 2012, IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society.

[3]  J. Alex,et al.  Fast switching, modular high-voltage DC/AC-power supplies for RF-amplifiers and other applications , 1995, Proceedings of 16th International Symposium on Fusion Engineering.

[4]  J. Alex,et al.  A high voltage power supply for negative ion NBI based on PSM technology , 1997, 17th IEEE/NPSS Symposium Fusion Engineering (Cat. No.97CH36131).

[5]  Marco Berkhout,et al.  Class-D Audio Amplifiers in Mobile Applications , 2010, IEEE Transactions on Circuits and Systems I: Regular Papers.

[6]  Malcolm J. Hawksford.  Modulation and System Techniques in PWM and SDM Switching Amplifiers , 2006 .

[7]  Lei Bo,et al.  Comparison of performance between bipolar and unipolar double-frequency sinusoidal pulse width modulation in a digitally controlled H-bridge inverter system , 2013 .

[8]  Zhengming Zhao,et al.  Design of voltage balancing control circuit for series connected HV-IGBTs , 2013, 2013 International Conference on Electrical Machines and Systems (ICEMS).

[9]  Xueqiang Zhang,et al.  IGBT series connection under Active Voltage Control , 2011, Proceedings of the 2011 14th European Conference on Power Electronics and Applications.

[10]  D. Shmilovitz,et al.  On the definition of total harmonic distortion and its effect on measurement interpretation , 2005, IEEE Transactions on Power Delivery.

[11]  M. Bataineh,et al.  Class D Switching Power Amplifiers: Theory, Design, and Performance , 2004, IEEE SoutheastCon, 2004. Proceedings..

[12]  W. Schminke.  The merits of modern technology for today's high power short-wave transmitters , 1988 .

[13]  Muhammad H. Rashid,et al.  Power Electronics Handbook: Devices, Circuits and Applications , 2010 .

[14]  Qing Li,et al.  A fully digital controller of high-voltage power supply for ECRH system on HL-2A , 2011 .

[15]  Douglas Self.  Audio power amplifier design handbook , 1996 .