Beijing Hiconics Eco-energy Technology Co., Ltd.
Beijing Hiconics Eco-energy Technology Co., Ltd.

Principle and Function of Static Reactive Power Compensator

Nov 24 , 2023

Static Var Compensator is originated in the 1970s and has now developed into a mature FACTS device widely used for load compensation and transmission line compensation (voltage and reactive power compensation) in modern power systems. In high-power grids, SVC is used for voltage control or to obtain other benefits, such as improving system damping and stability. Typical representatives of such devices are Thyristor-controlled reactors (TCR) and Thyristor-switched capacitors (TSC).


Understanding Static Var Compensators

SVC static var compensator is currently the most advanced reactive power compensation device. It no longer uses large-capacity capacitors or inductors to generate the required reactive power, but achieves a leap in reactive power compensation technology through high-frequency switching of power electronic devices. It is particularly suitable for dynamic reactive power compensation in medium and high-voltage power systems.


Static Var Compensator is a type of dynamic reactive power compensation device with no rotating parts, fast, smooth and controllable. It combines controllable reactors and power capacitors (fixed or grouped switched). Capacitors can generate reactive power (capacitive) while controllable reactors can absorb reactive power (inductive). By adjusting the reactors, the entire device can smoothly transition from generating reactive power to absorbing reactive power (or vice versa), and respond quickly.


Working Principle of Static Var Compensator

Its role in electronic power supply systems is to improve the power factor of the grid, reduce the losses of power transformers and transmission lines, improve power supply efficiency, and improve the power supply environment. Therefore, reactive power compensation devices play an indispensable and crucial role in power supply systems. Rational selection of compensation devices can minimize network losses and improve grid quality. Conversely, improper selection or use may cause factors such as voltage fluctuations and increased harmonics in the power supply system.


Functions of Static Var Compensators

Static Var Compensator is referred to devices that use different stationary circuit breakers to switch capacitors or reactors, enabling them to absorb and emit reactive currents. They are used to improve the power factor of the grid, stabilize grid voltage, suppress system oscillations, and perform other functions. In most static reactive power compensation devices, inductive reactive devices can achieve smooth and continuous level adjustment, while capacitive reactive devices are adjusted in stages. They provide capacitive or inductive reactive power to the grid in a static, fast, and continuous level, aiming to comprehensively improve the quality of voltage and meet power supply requirements, while also reducing grid active power losses, improving system stability, and reducing power frequency overvoltages.