Motor controller and method and system for adaptively changing IBGT gate-level resistance value of motor controller

Abstract

The invention discloses a motor controller and a method and system for adaptively changing IBGT gate-level resistance value of the motor controller, and the method comprises the following steps: (1),detecting the corresponding optimal gate-level resistance values of the motor controller under different working conditions, and obtaining a working condition-optimal gate-level resistance value corresponding relation; (2) in an operation state, measuring a current motor controller working condition, and determining an optimal gate-level resistance value corresponding to the current working condition according to the working condition-optimal gate-level resistance value corresponding relation; and (3) adjusting the gate-level resistance value in the IGBT drive circuit to the optimal gate-levelresistance value in the step (2). On the premise of ensuring safe operation of the IGBT, the loss of the IGBT can be reduced to the maximum extent, and the working efficiency of the IGBT is improved.

Description

technical field [0001] The invention relates to an IGBT driving method, in particular to a motor controller and a method and a system for adaptively changing the value of its IGBT gate-level driving circuit. Background technique [0002] The power electronic system is mainly composed of the main circuit and the control circuit. Among them, the main circuit is composed of switching devices such as IGBTs. The operating environment of high-power IGBTs is generally relatively harsh, and the voltage it can withstand can be as high as more than one thousand volts. If it is dealt with in time, it will cause very serious consequences. Especially in the field of new energy vehicles, IGBT is one of the core devices of the motor control unit in electric vehicles, and the design of the resistance value of the gate-level gate-level resistance is a key factor determining its working performance. [0003] The input voltage of the busbar of the motor controller is the output voltage of the...

AI Technical Summary

Problems solved by technology

[0003] The input voltage of the busbar of the motor controller is the output voltage of the high-voltage battery. Since the output voltage range of the high-voltage battery is wide (200V-450V) or higher, and the current IGBT gate-level resistors are mostly fixed resistance, in order to ensure that the IGBT gate is The turn-off voltage stress of the IGBT at the highest voltage and low temperature has a reasonable derating, and the gate-level resistance parameter needs to be increased, but a large gate-level resistance will increase the turn-off time of the IGBT, increase losses, and increase the junction temperature, resulting in IGBT Both the operating efficiency and the power density of the electric control are affected

by figure 1 For example, the BUS input voltage range of the existing controller is relatively wide, and the rated voltage of the electronic control works for a long time. In order to ensure a reasonable derating of the turn-off voltage stress of the IGBT under the highest voltage, it is necessary to increase the gate-level resistors R1 and R2 Design parameters, but obviously, larger R1 and R2 lead to longer turn-off time, greater IGBT loss, low efficiency, and increased junction temperature, sacrificing the power density of electronic control; on the contrary, if R1 and R2 parameters are designed too much small, in extreme cases, the IGBT may exceed the SOA safe operating area

[0004] In response to the above problems, the Chinese patent with the publication number CN209375598U provides an IGBT variable resistance turn-on circuit, which realizes the variable resistance turn-on through resistance voltage division, which reduces the risk during the operation of the IGBT to a certain extent, but it can only Realize the switching of two different resistance values, the resistance value cannot be adjusted adaptively, and the problem of low switching efficiency and large loss of IGBT cannot be fundamentally solved

[0005] The Chinese patent with the publication number CN107342759A provides a digital intelligent IGBT driving method and its system, which can be used to control the IGBT module to be turned on or off at a fixed time between power-on and power-off, further reducing the The operation risk of the IGBT is reduced, but it cannot adjust the resistance value of the gate-level resistor of the IGBT to the optimum, that is, it cannot maximize the reduction of loss and increase the power density of the electronic control

Images