Digital low-and-medium-frequency self-adaptive three-phase half-controlled rectifying device and triggering method thereof

Abstract

The invention discloses a digital low-and-medium-frequency self-adaptive three-phase half-controlled rectifying device and a triggering method thereof. The device mainly comprises a synchronous signal conditioning circuit, a digital control circuit and a pulse amplifying circuit. After passing through optically coupled isolation, alternating-current voltage signals are sent into the digital control circuit by the conditioning circuit; and a controller MCU (Microcontroller Unit) calculates the period according to the sent synchronous signals and updates a control angle so as to generate three paths of triggering signals. The pulse amplifying circuit amplifies the signals and then triggers a three-phase half-controlled bridge so as to implement controllable rectification. In the method, three phases are triggered in sequence according to a software program designed by the controller in the digital control circuit; and after a sampling voltage value and a preset voltage value are compared, the control angle is calculated by a PID (Proportion Integration Differentiation) digital controller so as to implement the closed-loop control of the rectified voltage. The invention implements the triggering rectification by frequency self-adaptive digital phase shifting within the working range of low-and-medium-frequency voltage. The invention has the characteristics of high symmetry degree of the output pulse, high anti-interference capability and high response speed, and the synchronous signal conditioning circuit is compact and reliable.

Description

Technical field [0001] The invention belongs to the technical field of power electronic equipment switch device control, and is mainly a digital mid-low frequency adaptive three-phase half-controlled rectifier device and a trigger method thereof. Background technique [0002] When the AC power output by the permanent magnet generator is not stabilized, when the load changes, the generator speed changes greatly, causing the amplitude and frequency of the three-phase AC power to change within a relatively large range. In order to obtain a stable output voltage, a more stable DC voltage is generally obtained through controllable rectification and then inverter is performed. However, the commonly used analog integrated trigger circuit is susceptible to various factors of the power generation equipment. When the frequency changes greatly, the peripheral circuit parameters need to be adjusted, the design is complicated and the debugging is difficult. The existing digital trigger circu...

AI Technical Summary

Problems solved by technology

However, the commonly used analog integrated trigger circuit is easily affected by various factors of power generation equipment. When the frequency changes greatly, the parameters of the peripheral circuit need to be adjusted, the design is complicated and the debugging is difficult.

The existing digital trigger circuit requires three synchronous signals as a reference for the controllable rectification of three-phase AC power, and uses a synchronous transformer for isolation and phase matching. The weight of the equipment is large, the components are many and the cost is high

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