DC solid-state power switch circuit

Abstract

A DC solid power switch circuit includes a main power circuit, a subsidiary power circuit parallel to the load, an isolated drive protection circuit composed of a drive supply, a drive isolation circuit, a slow turned-on-off control circuit, a discriminating control circuit, a short circuit protection circuit and a push and pull output circuit, a current detection circuit, a voltage detection circuit, a main power valve drive circuit, a light-coupled isolating circuit, an assistant power valve switch-on logic circuit and a power drive output circuit, which can limit the current impulse in the period of switching on capacitive load, and suppress the peak voltage in turning off the inductive load.

Description

[0001] Technical Field The present invention relates to a DC solid-state power switch circuit, which belongs to the field of power electronics and electrotechnical technology Background technique [0002] The specific implementation of the DC solid-state power switch circuit involves the following key technologies: [0003] 1. How to solve the problem of the peak voltage at both ends of the switch tube when the inductive load is turned off and the accumulated voltage caused by the leakage current of the power tube in the actual circuit. [0004] 2. Realization of inverse time overcurrent protection circuit [0005] At present, there are mainly logarithmic index method and curve fitting method in the realization of the analog circuit of inverse time overcurrent protection. The disadvantage of the two methods is that the realized inverse time characteristic overcurrent protection curve has large error and low precision. [0006] 3. Thermal memory function of the circuit [000...

AI Technical Summary

Problems solved by technology

[0014] Short-circuit protection is a necessary protection function for solid-state switches to work reliably. Short-circuit is the worst fault in the system. It is required that the solid-state switch must be able to deal with short-circuit faults in a very short moment (25μs), cut off the circuit, and protect the load and the circuit from damage. , and the "slow" turn-off makes the power tube cut off the load in a relatively long time; in addition, how to ensure that the power tube does not enter the short-circuit protection state during the normal turn-on process, these all have short-circuit protection functions and its relationship with "slow" turn-on "slow" "The Fusion Problem of Shutdown Technology

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