Switch tube control pulse driving method

Abstract

The invention relates to a switch tube control pulse driving method which comprises the following steps: an object pulse control signal is divided into two control signals that are the same in pulse width via a digital control chip, the two control signals are respectively connected to anti-phase totem poles after being output via the digital control chip, then the two control signals are respectively connected to two ends of a primary side winding of a pulse transformer via the anti-phase totem poles, a group of homonymous terminals at a secondary side of the pulse transformer are connected to form a place for driving output, the other group of homonymous terminals are respectively connected to anodes of two diodes, the signals are connected to a voltage divider resistor after two cathodes are connected with each other, then the signals are subjected to voltage dividing operation, the signals are connected to an input end of a driving chip, and an output end of the driving chip is connected with a gate pole current-limiting resistor of a switch tube in a power circuit. According to the switch tube control pulse driving method, a defect that a conventional electromagnetic isolation driving method and a conventional optoelectronic isolation driving method result in difficulty in designing a high frequency and high power density converter can be overcome. The switch tube control pulse driving method is high in responding speed, high in dielectric strength of the primary side and the secondary side, and strong in common mode interference suppressing capability; duty ratio constraints caused by a fact that the primary side of the pulse transformer needs magnetic recovery can be removed.

Description

technical field [0001] The invention relates to a drive circuit and configuration of a switch tube in a power converter, and belongs to the technical field of power electronics and electric engineering, in particular to a driving method for a switch tube control pulse. Background technique [0002] In the power electronic power conversion technology, the drive circuit is used as the connection hub between the power circuit and the control circuit. According to different power circuit topologies, there are two main methods of driving power switching devices: direct drive and isolated drive. In many applications, especially in high-power converters, it is generally necessary to achieve electrical isolation between the power circuit and the control circuit, and an isolated drive is required for this. [0003] Before the present invention was made, isolation driving was divided into two modes: electromagnetic isolation and photoelectric isolation. Among them, optoelectronic is...

AI Technical Summary

Problems solved by technology

However, due to the magnetic saturation characteristics of pulse transformers, traditional electromagnetic isolation driving methods are usually limited to applications where the duty cycle is less than 50%. For inverters and rectifiers, because the pulse control signal changes continuously within a low frequency cycle , and the duty cycle often needs to be adjusted in the range of 0 to 100%, which can easily lead to the saturation of the pulse transformer. In order to solve this problem, a high-frequency modulation circuit is usually added to the electromagnetic isolation drive circuit, but this will introduce high-frequency noise interference And increase hardware cost, complicate the driving circuit

It can be seen that the traditional electromagnetic isolation driving and photoelectric isolation driving methods are not easy to design high frequency and high power density power converters

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