Static Var Generator (SVG) also known as active power factor compensators (APFC) or instantaneous stepless reactive power compensators are the ultimate answer to power quality problems caused by low power factor and reactive power demand for a wide range of segments and applications.
They are a high performance, compact, flexible, modular and cost-effective type of active power filters (APF) that provide an instantaneous and effective response to power quality problems in low or high voltage electric power systems.
They enable longer equipment lifetime, higher process reliability, improved power system capacity and stability, and reduced energy losses, complying with most demanding power quality standards and grid codes.
Low power factor increases the active energy losses of installations and affects their stability. It is typically caused by inductive or capacitive loads that demand extra reactive power to perform properly. Other contributors to low power factor are harmonic currents produced by nonlinear loads and the change of load in the electric power system.
SVGs deliver real-time inductive or capacitive reactive power compensation. Rapid response time provides stable and accurate power factor correction without the drawbacks of conventional solutions like capacitor banks and reactor banks.
An Static Var Generator is a power electronics-based device connected in parallel with the load that requires harmonics mitigation. SVG works as a controlled current source providing any kind of current waveform in real time.
When the load generates inductive or capacitive current, it makes load current lagging or leading the voltage. An SVG detects the pase angle difference and injects in real time leading or lagging current into the electric power systems, making the phase angle of the current almost the same as that of the voltage, bringing fundamental power factor to unity.
Main benefits of ALBs can be summarized as:
1. Capability to deliver instantaneous capacitive and inductive reactive power compensation.
2. Optimized for highly dynamic applications where conventional capacitor banks or reactor banks are unable to track the loads.
3. Allow compensation of loads fed by generators without risk of overcompensation.
4. Inject reactive power that is required by the load at each instant into the system.
5. Over dimensioning not necessary: Compensation capacity equals the installed capacity.
6. Unaffected by network voltage drop. Full reactive current can be provided to meet required demand under reduced network voltage level.
7. Simple dimensioning and installation.
SVGs have many low and high voltage potential applications where their use offers many benefits.
⦿ Installations with fast changing reactive power demand like electric arc furnaces and ball mills.
⦿ Highly dynamic loads where the power factor fluctuates rapidly or in big steps like cranes, sawmill machinery, welding machines, etc.
⦿ Correction of leading power factor like in data centers allowing back-up generators operation.
⦿ UPC systems.
⦿ Solar inverters and wind turbine generators.
⦿ Railway electrification systems: Trains & trams
⦿ Loads with low power factor: Motors, cables, lightly loaded transformers, lighting, etc.