Driving power supply

Abstract

The invention relates to the electronic technology and discloses a driving power supply. The driving power supply comprises a push-pull switching power supply, a voltage stabilizing unit and a filtering unit, wherein the voltage stabilizing unit, the filtering unit and the push-pull switching power supply are connected; the voltage stabilizing unit is connected with the filtering unit; the push-pull switching power supply is used for respectively outputting a positive driving voltage and a negative driving voltage by a positive voltage output end VCC and a negative voltage output end VEE when a driving signal is received; the voltage stabilizing unit is used for stabilizing the positive driving voltage and the negative driving voltage; the filtering unit is used for filtering the positive driving voltage and the negative driving voltage, wherein the voltage stabilizing unit comprises a voltage stabilizing chip U1 and a voltage stabilizing diode V1; V1 is connected between the VEE and U1, and U1 is connected with VCC and the filtering unit; and the voltage stabilizing chip and the voltage stabilizing diode perform comprehensive voltage stabilization on the positive driving voltage and the negative driving voltage. Thus, a stable positive voltage can be obtained when the input voltage has little change, and the negative voltage of the driving power supply always exists when the input voltage reduces more, so that IGBT can be turned off reliably to prevent damage.

Description

technical field [0001] The invention relates to the field of electronic technology, in particular to a driving power supply. Background technique [0002] IGBT (Insulated Gate Bipolar Transistor, Insulated Gate Bipolar Transistor) is a widely used power electronic semiconductor device. Driving IGBT requires positive and negative power supplies. Although IGBT is a voltage-controlled device, driving IGBT still requires relatively large power. If the driving power fails, the IGBT is also very likely to be damaged during operation. [0003] At present, there are mainly two types of driving power supplies for IGBTs: [0004] Use flyback power supply plus primary side feedback drive power supply to directly output drive positive and negative voltages. Although this driving power supply has primary side voltage feedback, its output voltage does not participate in the feedback, so the output voltage will change when the load changes. Moreover, the primary side needs to have an ex...

AI Technical Summary

Problems solved by technology

The capacitance of the filter capacitor required by this driving power supply is relatively large, and the cost of the capacitor is high

Moreover, when the input voltage changes, the negative voltage will change greatly, and even the negative pressure will disappear, so that the IGBT cannot be turned off reliably, and the IGBT is easily damaged.

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