Voltage compensating method of serially connected electrically energy quality compensator

Abstract

A voltage compensation method of an electrical energy quality compensator in series is realized by rotating the phase angle of a loaded voltage as follows: 1. to determine the rotating range of the angle of the load voltage refernece vector according to the system fault voltage and the voltage compensation limit. 2. to calculate the energy optimization angle by using the load power factor and system fault voltage plus sequence components. 3. to combine the optimized angle determined in 2 and the angle rotating range determined in 1 to select the rotating angle of load voltage reference vector to enlarge the voltage compensation range to reduce the energy insertion.

Description

technical field [0001] The invention relates to a power quality compensation method, which belongs to the technical field of user electric power. Background technique [0002] With the development of science and technology, the degree of automation, digitalization and integration of production has been continuously improved, and the application of sensitive loads such as computers and automatic assembly line equipment has made power users have higher and higher requirements for power quality. Voltage quality problems that did not pose a major threat in the past have directly or indirectly affected the production of these sensitive users and reduced their economic benefits. A series power quality compensator (Series Power Quality Compensator, hereinafter referred to as SPQC) can effectively solve most power supply voltage quality problems. Series devices are a type of compensation devices that have emerged and developed in recent years, such as ABB’s DVR and Siemens’ SIPCON-...

AI Technical Summary

Problems solved by technology

[0006] Due to the existence of the above two limits, the design of the series device usually has to consider two aspects: one is the voltage compensation capability, that is, at the same DC side voltage V d Under the condition, how to compensate for a larger voltage drop; the second is the energy compensation capability, that is, at the same DC side voltage V d Under the condition of energy storage and energy storage, how to obtain a longer compensation time in the case of voltage drop

Most of the voltage drops are between 50% and 70%, but in order to reduce the capacity of the compensation device, after optimizing the design of the system (such as reducing the DC side voltage, changing the transformation ratio of the series transformer, reducing the capacity of the energy storage unit, etc.) , the limit of the output voltage of the series cells will be compressed

Usually this limit is designed around 50%, so when the existing compensation device is used, when the voltage drop is greater than 50%, the device cannot compensate

Energy compensation capability is related to energy storage units, which are usually expensive and require maintenance

However, the compensation method of existing devices does not consider the optimization of energy injection. Usually, under the same voltage compensation situation, the energy is not the minimum. In order to obtain a longer compensation time, the capacity of the energy storage unit is usually designed to be larger, so Reducing energy injection and reducing the cost of energy storage units has become another main content of improving device economy

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