Compensation Reactors for Capacitive Reactive Power
Compensation reactors, also known as shunt reactors, are used to absorb excess capacitive reactive power in electrical installations. This phenomenon is common in extensive cable networks, lightly loaded supply systems and installations with a high share of electronic equipment.
The reactor introduces inductive reactive power, helping stabilise the power factor and reduce charges associated with capacitive reactive energy. Single-phase and three-phase versions are available depending on the network configuration and required compensation power.
Although the mechanical construction may resemble a transformer, a compensation reactor has no secondary winding. Its purpose is to provide controlled inductive reactance, not to transform voltage.
Applications
Industrial plants with long cable routes, renewable-energy installations, data and telecommunications facilities, LED lighting systems, synchronous machines and other installations where capacitive reactive power occurs during low-load operation.
Design
The reactor uses a laminated electrical-steel core with designed magnetic air gaps and copper or aluminium windings. The material and conductor cross-section are selected according to rated power, current and thermal requirements.
Selection
Correct selection requires network voltage, frequency, measured capacitive reactive power, duty cycle, harmonic content, ambient temperature and enclosure conditions. Fixed or staged compensation can be designed depending on the load profile.