When the inverter is faced with abnormal working conditions, take down or other protective measures, as far as possible to protect the safety of the IGBT module. What factors will affect and even endanger the safety of the IGBT module?
1, voltage factor
(1) power supply voltage fluctuations, such as the DC loop filter (energy storage) capacitor loss, will cause the surge current and peak voltage generation, the IGBT module of the safe operation of the threat;
(2) IGBT control voltage driving voltage is low, will lead to incentive under IGBT, the conduction resistance increases, power consumption and temperature rise, easy to damage the IGBT module.
(3) when the power supply voltage of the IGBT module is too high, it will exceed the safe operating range, which leads to the breakdown of the module;
(4) when the power supply voltage is too low, the load capacity is insufficient, the running current is increased, the running motor is easy to generate the blocking phenomenon, which endangers the safety of the IGBT module;
2, temperature factor
(1) when the temperature rises to a certain amplitude, the shutdown protection;
(2) mild temperature rise, to the forced air cooling and other means;
3, current factors
(1) serious over current or short circuit condition, no time delay and quick break protection;
(2) over current, in light, moderate over current state, for anti time limit protection area;
4, other factors
(1) the abnormal driving circuit, such as the negative cut-off negative pressure control circuit of the interrupt, etc., will make the IGBT by the wrong touch and damage;
(2) control circuit, detection circuit is abnormal, such as reference voltage drift detection circuit, lead to action to protect the control point of change, has not enough protection.