PWM (Pulse-Width Modulation) three-level digital controller of zero-flux Hall large-current sensor

Abstract

The invention discloses a PWM (Pulse-Width Modulation) three-level digital controller of a zero-flux Hall large-current sensor. The PWM three-level digital controller comprises a PWM carrier wave triangle generation and regulation circuit, a Hall chip signal collection and negative feedback PID (Proportion Integration and differentiation) control parameter circuit, a three-level circuit and a square wave signal generation circuit; the PWM carrier wave triangle generation and regulation circuit is utilized to generate a positive carrier wave signal and a negative carrier wave signal, the Hall chip signal collection and negative feedback PID control parameter circuit collects a Hall voltage signal by utilizing a difference amplification circuit, and outputs proper feedback voltage by regulating the negative feedback PID control parameters, the feedback voltage and the carrier wave signals are intersected, different square wave signals are generated through control at intersection moment, the square wave signals control the on and off of four transistors in the three-level circuit and outputs the voltage, a compensation coil generates current, and the value of the current is measured out. The PWM three-level digital controller can measure large current, is high in current signal measurement frequency and low in cost, and solves the problems of influences on the large-power consumption radiation and voltage grade improvement of the transistors under large-current conditions.

Description

technical field [0001] The invention mainly relates to the design of a novel digital controller of a zero-flux Hall high-current sensor. Background technique [0002] The DC test platform of the ITER power supply and the PF power supply system of the future ITER power supply require a high-current bipolar sensor with a range of 45KA, but there is a lack of such current sensors in the domestic and foreign markets. The new fiber optic current sensor can measure large currents, but the frequency response of the measured current signal is not high, and the price is expensive. The price of the 45KA range sensor is also about 450,000 RMB. The ITER power supply device needs many current sensors, and the cost is quite high. High. [0003] The Hall zero-flux Hall bidirectional current sensor on the market, its controller is designed based on an analog circuit. When the sensor measures the current, its main output transistor is working in an amplified state, with an output resist...

AI Technical Summary

Problems solved by technology

However, in the case of a large current exceeding 20KA, the current of the secondary compensation coil will be very large, reaching the order of amperes. At this time, the power consumption of the transistor is very large, and it may be tens of watts to hundreds of watts.

With such a large tube loss, when designing heat dissipation, it will be very difficult to rely on air cooling alone.

In addition, in the case of high current, in order to pursue a larger compensation current, the voltage level of the controller must be increased, and the increase in voltage level will affect the selection of transistor components in the complementary push-pull power circuit, so the high power dissipation and voltage of the transistor The level problem directly limits the application of analog controllers in high current occasions

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