Self-adaptive action control method of alternating-current contactor

Abstract

The invention discloses a self-adaptive action control method of an alternating current contactor and belongs to the technical field of electrical intelligent control. According to the self-adaptive action control method of the alternating current contactor, the fault ride-through capability of a motor can be given to full play, so that the alternating current contactor can realize self-adaptive action according to a fault type, duration time and the magnitude of load torque; off-line calculation and on-line analysis are combined, so that the alternating current contactor under voltage sag canmake a quick response, the production continuity under most voltage sag can be guaranteed, the alternating current contactor under severe voltage sag can trip off the motor in time, and the safe operation of the motor is guaranteed; a motor double-cage rotor model is adopted, changes of rotor parameters along with the rotating speed are considered, and dynamic behaviors of the induction motor inthe stall and acceleration process can be well represented. In the self-adaptive control process, the original structure and functions of the alternating current contactor are not damaged, only simplecapacitor type energy storage delay elements need to be additionally arranged, an economic effect is remarkable, and engineering practicability is achieved.

Description

technical field [0001] The invention relates to the technical field of electrical intelligent control, in particular to an adaptive action control method for an AC contactor. Background technique [0002] With the continuous development of modern industry, the voltage sag-sensitive equipment in the power system is gradually increasing, which reduces the anti-disturbance ability of the production process and makes the economic losses and safety risks caused by voltage sag increasingly prominent. AC contactors are widely used in the control of motors, lighting, and electric heating loads, but they are also very typical voltage sag sensitive devices. In recent years, incidents of motor stall and even production process interruption caused by AC contactor tripping have occurred from time to time, which have brought huge losses to continuous production industries such as papermaking, metallurgy, and chemical industry. In fact, since the motor itself has a certain inertia, it can...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problem of the voltage sag immunity mismatch between the existing motor and the AC contactor, the present invention proposes a control method for realizing the adaptive action of the AC contactor, which can give full play to the fault ride-through capability of the motor load itself , to minimize unnecessary unplanned interruptions to the production process

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