Compact and high repetitive pulsed power modulator based on semiconductor switches

Abstract

This paper describes the design of a compact and highly repetitive pulsed power modulator based on semiconductor switches. Output specifications of the proposed modulator are as follows: variable output pulse voltage, 1-10 kV; width, 1-10 µs; pulse repetition rate (PRR), 1-50,000 pps; and average output power, 10 kW. The proposed solid-state pulsed power modulator has two main parts: an IGBT stack that hasa gate drive circuit for the pulse output with a variable pulse width and repetition rate, and a capacitor charger that has a controllable output voltage. To connect all the storage capacitors in a series for high voltage pulses, a simple and reliable IGBT stack structure was proposed based on the Marx generator. In addition, the gate driver circuit, which supplies power and signals to all the IGBTs simultaneously, was introduced. This providesa superior protection function against the arc and the short. To charge the storage capacitors, a novel 10 kW (10 kV, 1 A) high voltage capacitor charger with the combined advantageof a series-loaded resonant converter and a ZVS (zero-voltage-switching) full-bridge pulse width modulation (PWM) converter was proposed and designed especially for the solid-state pulsed power modulator. Theexperiment results verified that the proposed scheme and structure can be used effectively for a high voltage pulsed power modulator that requires variable voltage, repetition rate, and pulse width, depending on the process of the applications.

Design of a High-Efficiency 40-kV, 150-A, 3-kHz Solid-State Pulsed Power Modulator

“…Fig. 2 shows the scheme of the proposed gate driver which is a modified driver circuit suggested in [15]. By disconnecting a diode connected between the IGBT collector and MOSFET M1 source, only discharging the input capacitance of IGBT through the resistor is enabled for arc protection.…”

“…By doing so, there is a limit to the decreasing the rising time. To overcome this limit, the study on the solid-state pulsed power modulator based on power cells connected in a series has been conducted [14], [15]. When compared to [11], much more rapid rising time can be achieved.…”

“…It can be configured with a charging inverter and pulse generator part. For the pulse generator part, a novel gate driver has been proposed to protect the pulsed power modulator from the arcing condition [14], [15]. By adopting an IGBT which can handle 1200 A for a short time, rising time is limited at 300 ns [14].…”

“…Last, a modified gate driver excluding short protection is suggested. Since pulse width is relatively short for the environmental application, short protection suggested in [14], [15] is not necessary.…”

“…For a charging inverter, a resonant converter has been adopted for high-efficiency operation [13]- [15]. In particular, a series-loaded resonant (SLR) inverter operating in discontinuous conduction mode (DCM) has been adopted to generate 60 kV of pulsed power [14].…”