Technology

Reactive Power Compensation

It is well known that among the various modes of reactive power compensation available, the use of shunt capacitor is the most widespread. Shunt capacitors are widely employed in distribution systems of different types viz., industrial, residential and rural. Series Compensation is employed to improve the Power Transfer Capability of Power System and to reduce the transmission system losses. ABB is reputed world wide for its capabilities in these areas. ABB is committed to inducting into India world class technologies in areas relating to manufacture of HV Shunt Capacitors and application of Shunt Capacitors – from the simple Shunt capacitor Banks to more sophisticated Harmonic Filter Banks, Static Var Compensators (SVC) and Series Capacitors. A Package Deal ABB's Engineering Capabilities and inhouse supporting products such as Switchgear, Control and Relay panel, etc., provides an opportunity for users to look for a package deal of Reactive Power Compensation for their system. This includes Application Engineering, Product selection, supply, erection, testing and commissioning of : 

• Shunt Capacitors for PF Correction

• Harmonic Filter Banks for reducing

• Harmonic Distortion in Industrial Plants.

• Static Var Compensators ( SVC )

• Series Capacitors

Please refer attached table to know more about the system solutions, ABB offers. HV Capacitors ABB manufactures state of art HV Power Capacitors made up of 'ALL P.P. film' dielectric impregnated with Non-PCB compound which are environment friendly and have carried out'Endurance Test' on various designs of Capacitor which assures long life of capacitor, as high as 20 years. ABB takes pride of a very low field failure rate in their capacitors.

Application Engineering of HV Power Capacitors 1. Shunt Capacitors for PF Correction The efficiency of power generation, transmission and distribution can be appreciably improved by operating the system at near unity power factor. This increases real power availability and improves the economics related to power handling. Upon installation of this system, the following benefits can be obtained :

• Voltage improvement

• Reduced kVA demand

• Penalties avoided

• Early pay back of investment etc.

ABB has supplied these systems to many prestigious customers in India viz., TNEB, MSEB, GEB, WBSEB, UPSEB, KEB etc., where the equipments
are giving satisfactory service.
2. Harmonic Filter Banks
Diverse loads in a power network generate harmonics. The main sources of harmonics are thyristor controlled equipment-such as rectifiers, speed
controlled drive systems and furnaces. Harmonics in a power network cause problems, such as:

• Increased losses in motors, transformers and cables leading to dangerous over heating

• Over loading of Capacitors

• Damage or malfunction of electronic equipment

• Telephone Interference

• Malfunction of relays in remote control equipment, etc.

The most common method of solving these problems is by installing Harmonic Filter. A Harmonic Filter is built up from passive RLC components i.e., capacitors and reactors. They are sized so that they together form a tuned circuit. The tuning frequency is matched to the dominant harmonic; normally 3rd, 5th, 7th and 11th. By installing harmonic filters several benefits are obtained.

• Power Factor correction

• Filtering of harmonics in the system

Avoidance of resonance problems between the inductive and the capacitve parts of the network. ABB is reputed for system solutions involving Harmonic Filters and have given our systems to many prestigious industrial customers in India viz., DSP, TISCO, Hindalco, Lloyd Steels, Lakshmi
Cements, PACL etc., where they are giving satisfactory service. 3. Static Var Compensators (SVC) Certain loads viz., furnaces, rolling mills
etc., vary from time to time and consequently there is a dynamic variation in the reactive power balance. A rapidly operating static var compensator can
continuously control the reactive power throughout the entire absorption and generation range of reactive power. The ABB static var compensator includes the following major components, making up a controlled static compensator:

• Thyristor valves 

• Reactors

• Capacitor Banks 

• Power transformer

• Control System 

By installing this system several benefits
are obtained:

• Stability of voltage in weak systems

• Reduced transmission losses

• Increased transmission capacity, thus delaying the need for new lines

• Increased transient stability limit

• Increased damping of small disturbances

• Damping of power swings

• Improved voltage control & stability

SVC installations in India are very few. ABB has supplied SVC installations at few places in India including Salem Steel Plant where they are giving satisfactory service. 4. Series Capacitors Series Capacitors are connected in transmission and distribution lines to :

• Increase power transfer capability

• Improves voltage regulation and reactive power balance

• Optimize load sharing between parallel lines

• Reduces system losses

The Series Capacitor installations in India are few in number.