Driving method and device for IGBT provided with push-and-pull isolating power source

Abstract

The invention relates to the technical field of IGBT driving and provides a driving method and device for an IGBT provided with a push-and-pull isolating power source. The driving device adopted in the method comprises a primary side driving circuit, a secondary side driving circuit and a push-and-pull DCDC isolating power source circuit; a PWM shaping circuit of the primary side driving circuit is connected with the input end of the secondary side driving circuit through a photoelectric isolating circuit; the feedback end of the secondary side driving circuit is connected with a fault signal latch circuit of the primary side driving circuit through a fault feedback circuit; the output end of the secondary side driving circuit is connected with an IGBT module; the input end of the PWM shaping circuit, the output end of the fault signal latch circuit and the push-and-pull isolating power source circuit are connected with a driver interface. By controlling primary and secondary distributed capacitance of a transformer, the common-mode rejection capacity of the driving device is improved, and the anti-jamming capability of the driving device is enhanced; the isolating power source circuit is simplified, and the cost of the driving device is lowered; the size of the driving device is reduced, and the driving device is high in practicability and reliability.

Description

technical field [0001] The invention relates to the technical field of IGBT driving, in particular to an IGBT driving method and device configured with a push-pull isolated power supply, which is suitable for compact and low-cost IGBT driving occasions. Background technique [0002] In IGBT applications, the IGBT drive device not only plays an important role in the reliability of the entire system, but also has an important impact on the miniaturization and low cost of the entire system. Because the drive circuit using the dedicated IC with photoelectric isolation technology as the core device has the characteristics of flexible design, small size, high stability and reliability, it is widely used in IGBT applications that require high system volume and cost. The drive circuit using a special IC for photoelectric isolation technology generally needs to be configured with an isolated power supply outputting a positive and negative common ground voltage to form a complete set ...

AI Technical Summary

Problems solved by technology

It can be seen from the above schemes that some of these driving devices have low utilization rate of isolated power transformers, some circuits use more components, and some increase the complexity of transformer windings, resulting in high cost of driving devices. Big size

At the same time, the secondary winding of the isolated power transformer is complicated, which not only increases the difficulty of transformer design, but also is unfavorable to the size and cost of the transformer; more importantly, the complexity of the secondary winding of the isolated power transformer makes the distributed capacitance of the primary and secondary sides of the isolated power transformer difficult. control, resulting in a decrease in the ability of the driver's primary and secondary sides to suppress common-mode interference, a decrease in the anti-interference ability of the drive device, and unstable factors in the system

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