Instantaneous protection tester and operation method thereof

Abstract

The invention provides an instantaneous protection tester and an operation method of the instantaneous protection tester, and relates to an emergency protection circuit device used for limiting the over-current or the overvoltage without cutting off a circuit. The tester is composed of a control portion and an execution portion, wherein the control portion comprises a single-chip microcomputer, a voltage transformer, a current transformer, second-order band-pass filtering circuits, common frequency rectangular wave conversion circuits, a voltage boosting circuit, a key, an LCD display and chip 74LS04 circuits. The execution portion comprises a drive circuit composed of an MOC3021 optical coupler and a double-direction silicon controlled rectifier. The frequency of the voltage of the electric system and the power factor angle of the electric system can be directly and automatically detected, phase selection switch-on and switch-off can be achieved for the system, after the electric system is switched on, the magnitude of the current passing through an electric appliance product and the time when the current passes through the electric appliance product are detected in real time, display is conducted through a human-computer interaction interface, and meanwhile the backup protection function, namely, the timed switch-off function, is achieved.

Description

technical field [0001] The technical solution of the present invention relates to an emergency protection circuit device for limiting overcurrent or overvoltage without cutting off the circuit, in particular to an instantaneous protection tester and its operating method. Background technique [0002] The operation of the switchgear in the power system will produce electromagnetic transient phenomena that may endanger the normal operation of the power equipment, such as overvoltage and overcurrent, etc., and its severity is often related to the phase angle of the voltage or current when the switch is opened and closed. Therefore, as early as the 1970s, people began to study the phase selection opening and closing technology, that is, how to reduce or even eliminate this phenomenon by controlling the opening and closing phase angle. CN201789337U discloses a phase selection opening and closing control device, including a CPU module, an AC analog input plug-in, a switch value tr...

AI Technical Summary

Problems solved by technology

CN201789337U discloses a phase selection opening and closing control device, including a CPU module, an AC analog input plug-in, a switch value transmitter signal input plug-in, a power supply module, and a switch output plug-in. The defect of this utility model technology is that the current sampling Poor accuracy and poor anti-interference ability

In addition, the prior art transient protection test has the disadvantages of inflexible operation, low measurement accuracy, and poor human-computer interaction function

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