A Transistor-Based Assist Gate Driver of SiC MOSFET for Crosstalk Suppression in a Phase-Leg Configuration

Abstract

Crosstalk in a phase-leg configuration significantly limits the high switching performance of silicon carbide (SiC) MOSFETs and results in additional switching loss, self-excited oscillation and even parasitic conduction. To give full play to the fast switching potential of SiC MOSFET, this paper proposes a negative voltage transistor-based assist gate driver (NVTAGD) to suppress the voltage spike caused by the communication. First, a simple circuit composed of capacitor, resistor and diode is applied to establish a negative gate-source voltage level. Then, two auxiliary transistors cooperate with capacitors and diodes to actively suppress the positive and negative gate-source voltage spike. The auxiliary transistor can flexibly adjust its working mode according to the operation states of the circuit without additional control signals. Finally, parameter design criteria of main components are also given to meet different operating conditions. A double-pulse experimental setup based on SCT3022AL SiC MOSFET is established to illustrate the effectiveness of the proposed method. The proposed NVTAGD generates a negative voltage of -2.3 V for the synchronous freewheeling device. And the positive and negative crosstalk voltage spike decreases by 52.6% and 44.9% respectively. Both positive and negative crosstalk voltages are limited by the safe range. A series of experimental results illustrate that the proposed method not only suppresses the crosstalk voltage but also increases the reliability of the devices.INDEX TERMS Crosstalk suppression, silicon carbide (SiC) MOSFET, assist gate driver, phase-leg configuration, auxiliary transistors

Design and Implementation of Improved Gate Driver Circuit for Sensorless Permanent Magnet Synchronous Motor Control

“…The precision of the signal must be maintained to achieve good performance in the control process. An important problem is the behavior of the power switching components [13][14][15]. In this case, the effect of power switching components influences the signal information used in motor control processing, such as current information and the motor rotor position.…”

“…In this case, the effect of power switching components influences the signal information used in motor control processing, such as current information and the motor rotor position. Many studies have reduced this effect by implementing compensation using digital processing in computing systems [15,16]. However, because this does not significantly weaken the effect of the switching component behavior, this effect still occurs in the motor drive control system.…”