Static var generator for three-phase power grid

Abstract

Disclosed in the invention is a static var generator for a three-phase power grid. The static var generator is composed of a main controller, a power supply module, a power grid side data acquisition module, a load side data acquisition module and a reactive power compensation module. The power grid side data acquisition module consists of a power grid side current transformer, a first current conversion voltage circuit, a first voltage follower, a power grid side voltage transformer, a first voltage sampling circuit and a first voltage zero crossing detection circuit, wherein the power grid side current transformer, the first current conversion voltage circuit and the first voltage follower are connected successively and the power grid side voltage transformer, the first voltage sampling circuit and the first voltage zero crossing detection circuit are connected successively. The load side data acquisition module includes a load side current transformer, a second current conversion voltage circuit, a second voltage follower, a load side voltage transformer, a second voltage sampling circuit and a second voltage zero-crossing detection circuit, wherein the load side current transformer, the second current conversion voltage circuit, and the second voltage follower are connected successively and the load side voltage transformer, the second voltage sampling circuit and the second voltage zero-crossing detection circuit are connected successively. Besides, the reactive power compensation module includes a protection circuit, an isolated driver, a rectifier circuit, a charging relay, a three-phase inverter circuit and a relay protection circuit, wherein the isolated driver, the rectifier circuit, the charging relay, the three-phase inverter circuit and the relay protection circuit are successively connected. The static var generator has advantages of novel design, simple structure, complete functions, and high practicability.

Description

technical field [0001] The invention belongs to the technical field of three-phase power grids, and in particular relates to a static var generator for three-phase power grids. Background technique [0002] In recent years, with the diversification of power products and the complexity of power equipment, it has caused certain interference and pollution to electric energy, threatened the quality of electric energy, affected the safe operation of the power supply system, and could not guarantee the safe and stable power consumption of users. , For example, what we use in our life is power frequency alternating current. When it passes through a pure resistive load, the current generated is the same as the power frequency voltage. In reality, there are a large number of nonlinear components such as motors that generate harmonics and even cause Distortion of current, thus generating reactive power. Reactive power not only increases the capacity of power supply equipment, transmi...

AI Technical Summary

Problems solved by technology

[0002] In recent years, with the diversification of power products and the complexity of power equipment, it has caused certain interference and pollution to electric energy, threatened the quality of electric energy, affected the safe operation of the power supply system, and could not guarantee the safe and stable power consumption of users. , For example, what we use in our life is power frequency alternating current. When it passes through a pure resistive load, the current generated is the same as the power frequency voltage. In reality, there are a large number of nonlinear components such as motors that generate harmonics and even cause Distortion of current, thus generating reactive power

Reactive power not only increases the capacity of power supply equipment, the capacity of the transmission grid, and line losses, but also increases the voltage drop of transformers and lines. Impulsive reactive loads will cause violent voltage fluctuations and cannot guarantee the quality of power supply.

Most power supply protection uses anti-interference to block such threats, and cannot eradicate unsafe power quality problems. Therefore, a device that can effectively compensate this reactive power system is needed now, through the power grid and A static var generating device is installed between the loads to detect the required reactive power in the power grid, and send reactive power of equal size and opposite phase through the signal processor, that is, reverse reactive power is generated, which interacts with forward reactive power Offset, realize the balance of reactive power, ensure the high power factor operation of the power grid system, widely used, and have great practical value

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