IGBT is the "CPU" of power electronics, which plays an important role in the variable current and control of power electronics. However, in the working process of IGBT module, if the module loss is too large, with the heat difficult to dissipate, it will lead to very high internal temperature, the production of gas burst through the shell, this is called IGBT explosion.
The cause of IGBT explosion usually includes the following:
First, internal cause
The heating power exceeds the heat dissipated power, resulting in overheating, resulting in the explosion.
Second, human causes
(1) The inlet wire is connected to the terminal of the outlet wire;
(2) the inverter is connected to the wrong power supply;
(3) Do not attach the load device as required.
Third, common causes
(1) Overcurrent: one is a load short circuit, the other is the control circuit logic interference, resulting in the upper and lower bridge arm elements straight through;
(2) damage of insulation;
(3) Overvoltage: it is usually caused by the peak voltage generated by the stray inductance of the circuit under the action of very high DI/DT. The solution is to design a high-performance absorption circuit to reduce the stray inductance of the circuit.
(4) Overheating: IGBT is not fully conductive, in the presence of current component loss increases, temperature increases, resulting in damage;
(5) Communication error rate
a. After a period of communication, sudden misinformation causes IGBT to mislead the explosion;
b. The unstable operation of the FPGA program on the communication board causes the IGBT to mislead the explosion.
Fourth, other causes
(1) the reaction time of the overcurrent detection circuit in the circuit cannot keep up;
(2) process problems, screw is not tighten, etc.
(3) short-term large current, such as the main circuit overvoltage, absorption circuit is not done well, etc.;
(4) driving power supply is also a problem that should be paid special attention to, the need for the isolation is isolated, the need for the filtering is filtered;
(6) the motor impact feedback voltage is too large so that cause the IGBT to explode, but the probability of the explosion on charging is not very large.
(7) When the motor starts, the input voltage drops instantaneously and the capacitance discharges; IGBT explosion is caused by the excessive surge current of capacitor charge after the input voltage is restored.
NTC thermistor chip for IGBT produced by EXSENSE Electronics Technology Co., Ltd., which plays the role of temperature monitoring and temperature control in the IGBT module, it can ensure the normal operation of the module, to prevent accidents.