Static var corrector

Abstract

Disclosed is a static VAR corrector. A system for providing reactive power compensation to a utility power network includes a switch coupled to the utility power network, and a capacitor coupled with the switch for providing a controlled amount of reactive current based on conditions of the utility power network. The system also includes a switchable power dissipation device coupled in series to the capacitor and configured to provide a preselected amount of impedance to the reactive current for a predetermined duration when a line voltage on the utility power network drops below a threshold.

Description

technical field [0001] This application relates to static var correctors (SVC). Background technique [0002] Static Var (VAR) correctors (also known as Static Var Compensators) are electrical devices that provide reactive compensation to the transmission network. SVCs are commonly used in a variety of applications including, for example, regulating utility line voltage, improving network steady state stability, and establishing near unity power factor on transmission lines. [0003] Typically, an SVC includes a bank of controllable capacitors that can be switched in and out of the circuit, respectively, by a bank of semi-conducting switches, such as thyristors. Each switch is driven by an electrical gating signal generated based on line conditions, allowing the corresponding capacitor to discharge and conduct in a controlled manner. When using thyristor switches capable of responding to gating signals within sub-cycles (eg, on the order of milliseconds), SVCs can provide...

AI Technical Summary

Problems solved by technology

However, this reactor-capacitor coupling does not prevent resonance under low voltage conditions (for example, when reactive power from the SVC is expected to restore the utility line voltage after a temporary blackout or voltage sag)

Images