Serial power quality compensator based on alternating current (AC)/AC chopper

Abstract

The invention discloses a serial power quality compensator based on an alternating current (AC) / AC chopper. The serial power quality compensator consists of an AC / AC chopper circuit, a compensation transformer and an output filter circuit. The serial power quality compensator has the advantages of: having no reactor of an induction regulating compensator, and reducing the whole volume weight when the compensation transformer works in the state of high-frequency modulation; carrying out stepless smooth regulation on an output voltage so as to have quick dynamic response; carrying out control on an instantaneous value of the output voltage, having high sinusoidal quality of the wave form of the output voltage, and playing a role in inhibiting voltage flickering of an outside power grid, harmonic wave and the like; and being simple in circuit structure and easy in implementation, and having less used devices in the AC / AC circuit and less circuit overhead.

Description

1. Technical field [0001] The invention relates to a series power quality compensator based on an AC / AC chopper, belonging to an AC voltage stabilizer in a power conversion device. 2. Background technology [0002] The voltage of the external power grid in our country fluctuates greatly, and there are various interferences. Especially in recent years, with the development of the national economy, the demand for electricity has risen rapidly, and the gradual popularization of nonlinear equipment such as power electronic devices has caused serious harmonics to the power grid. Pollution seriously affects the normal operation of instruments and household appliances. Therefore, AC voltage stabilizers have become indispensable power supply equipment for many important equipment. At present, there are many types of AC voltage regulators in practical application, including magnetic saturation voltage regulators, parametric voltage regulators and compensation voltage regulators. Amon...

AI Technical Summary

Problems solved by technology

The contact voltage regulator uses a servo motor to change the secondary voltage of the voltage regulator to change the compensation voltage, and the response speed is slow. The main problem is that due to the contacts, the mechanical transmission system is noisy, easy to wear, large in size, high in cost, and difficult to maintain.

Compared with the magnetic saturation voltage stabilizer, the compensating AC voltage stabilizer with thyristor or relay has greatly improved the accuracy and efficiency of voltage regulation, but still uses a heavy and bulky reactor as the main regulating circuit; The compensated AC voltage stabilizer with sense still has mechanical contacts, and the AC voltage stabilizer with thyristor sense adjustment is prone to common conduction of the thyristor during the adjustment process, causing damage to the thyristor; and this sense-adjusted AC stabilizer The output voltage of the transformer is regulated with poles, the output voltage is not smooth, it can only adjust the effective value, it has no ability to adjust or suppress the distortion of the input voltage waveform, and the sine degree of the output voltage cannot be adjusted

In short, all kinds of AC voltage stabilizers currently used have obvious defects, especially the inability to effectively eliminate various electromagnetic disturbances, which has become a major issue faced by power supply technicians in our country

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