rwwengheaderActive Harmonic Filtering, STATCOM and SVC

Active filtering technology can be applied to industrial or commercial environments where good power quality is essential.

It can be used to improve the power quality of variable speed drive-fed motors, compressors, pumps, conveyors, shredders, mixers, extruders, winders, grinders, crushers, DC Drives, welding equipment and UPS (Uninterrupted Power Supply) systems.

RWW has developed a wide range of active harmonic filtering solutions to meet the needs of our customers in different market segments. Active harmonic filters are designed for dynamic reactive power compensation and harmonic filtering.

Active harmonic filters have a fast and dynamic response to voltage variations and harmonic distortions that improves the reliability of your plant and extends its operational life. By improving power quality, active filters increase process machinery uptime. That results in better productivity, reduced maintenance costs and therefore, higher profitability.

Energy losses and breakdown of key components of electrical systems such as capacitor banks, transformers, switch-gears, bus bars and cables can also be significantly reduced with Active Harmonic filters.

STATCOM is the name given to the semiconductor based counterpart of synchronous condenser. Synchronous condenser is actually an unloaded synchronous generator which is used to provide reactive power (both capacitive and inductive) to the network by changing its field excitation. STATCOM is much faster than the synchronous condenser, since it has no moving parts. It consists of semiconductors with turn-off capability, such as GTOs, IGBTs, and IGCTs and passive elements such as inductors, capacitors, and resistors. The use of STATCOM is generally, but not limited to, reactive power compensation and/or voltage regulation. It can also provide power system stability improvement.

A STATCOM, being nearly in phase with the network, can act as a capacitor (provides reactive power to the grid), when its voltage magnitude is higher than the grid’s. On the contrary, it can act as an inductor (absorbs reactive power from the grid), when its voltage magnitude is lower than the grid’s.

Some of the important benefits of STATCOM are:

  • Low response time, in the order of milliseconds
  • Prevention of transient currents and voltages
  • Lower disturbance in the network
  • Can provide both inductive and capacitive reactive power
  • Independent three phase operation
  • Current is not dependent on grid voltage magnitude
  • Fast, active compensation

The use of TCR (thyristor controlled reactors) together with Harmonic Filters is often referred to as an SVC. Since the amount of reactive power absorbed by TCR can be changed through the firing angles of thyristors, the total SVC output reactive power is under control. According to the needs of the load, either reactive power limitations may be met, or voltage regulation at the connected bus might be enhanced.

The most remarkable benefits of SVC are:

  • Low response time, in the order of milliseconds
  • Prevention of transient currents and voltages
  • Lower disturbance in the network
  • Ability to provide inductive & capacitive reactive power on demand
  • Independent three phase compensation – unbalanced compensation

Benefits & Disadvantages

Benefits

  • Large harmonic reduction
  • Compact
  • Can be scaled to higher voltages
  • Reactive power compensation
  • Can be used on applications with high harmonics and low reactive power

Disadvantages

  • Technically advanced
  • Expensive

Benefits

  • Fast Reactive power compensation
  • Voltage support – 20-60ms response

Disadvantages

  • Requires large amounts of space
  • Complex control and protection
  • Requires large filters to reduce harmonic
  • Output dependent on voltage
  • kW losses can be high

Benefits

  • Integrated harmonic filtering
  • Fast Reactive power compensation
  • Voltage support (<1ms response)
  • Smaller footprint than SVC

Disadvantages

  • Complex control and protection
  • Expensive
GO TO MERUS POWER WEBSITEHarmonic Filtering (Passive)Grid Code Compliance