TBEA compensation soft starting device used for large power cage type motor

Abstract

The invention provides a TBEA compensation soft starting device used for a large power cage type motor, and belongs to the technical field of large power cage type motor soft staring. The soft starting device mainly solves the problems of switch-on surging impact and by-pass jumping impact currents of autotransformer starting, and is mainly characterized in that an iron core shaped like a Chinese character 'tian' is divided into an autotransformer structure and an electric reactor structure, and is provided with an independent auto winding and an independent reactance winding. A first external connection port, a second external connection port, a third external connection port and a fourth external connection port are respectively connected with a self-excitation starting breaker, a by-pass self-excitation winding breaker, a starting compensation breaker, a connection breaker and one end of a series excitation control breaker, a starting idle work compensation unit is serially connected between the other end of the starting compensation breaker and a star point common terminal, the other end of the connection breaker is connected with the motor and one end of a by-pass operation breaker, and the other end of the by-pass operation breaker is connected with a bus. The soft starting device has the advantages of weakening surging at an auto starting moment and restraining by-pass phase step impact, and is mainly used for the large power cage type motor.

Description

technical field [0001] The invention belongs to the technical field of cage-type high-power motor soft start. In particular, it relates to a main circuit for a high-power cage-type special-type transformer compensation soft starter. Background technique [0002] At present, with the rapid expansion of my country's industrialization process, in key energy-consuming enterprises in my country's secondary industrial structure (such as steel, chemical industry, etc.), high-power motors with a high voltage of 10,000kW or more are used more and more frequently. The strength of the power grid (minimum short-circuit capacity), tolerance margin (voltage fluctuation range), and disturbance intensity (reactive starting current impact) are all a strong test. There are fewer and fewer forms that can be realized for power cage motors. Whether it is possible to find a starting method that minimizes the reactive power inrush current at the moment of motor starting and has less fluctuations in...

AI Technical Summary

Problems solved by technology

[0006] Third, when the autotransformer switches to the bypass full-voltage operation, the motor speed is close to the rated speed, and the motor changes from the step-down starting state to the full-voltage and full-speed state. Due to the sudden change of the voltage at the motor terminal, an instantaneous jump and surge current will be generated.

[0007] Therefore, traditional step-down starting methods (such as water resistors, reactors, autotransformers, etc.) have certain limitations in terms of grid-side starting current limitation and surge impact weakening.

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