09-01-2016, 01:48 PM
Introduction
We always in practice to reduce reactive power to improve system efficiency .This are acceptable at some level. If system is purely resistively or capacitance it make cause some problem in Electrical system. Alternating systems supply or consume two kind of power: real power and reactive power.Real power accomplishes useful work while reactive power supports the voltage that must be controlled for system reliability. Reactive power has a profound effect on the security of power systems because it affects voltages throughout the system.Find important discussion regarding importance about Reactive Power and how it is useful to maintain System voltage healthy.
Importance of Reactive Power
Voltage control in an electrical power system is important for proper operation for electrical power equipment to prevent damage such as overheating of generators and motors, to reduce transmission losses and to maintain the ability of the system to withstand and prevent voltage collapse.Decreasing reactive power causing voltage to fall while increasing it causing voltage to rise. A voltage collapse may be occurs when the system try to serve much more load than the voltage can support.When reactive power supply lower voltage, as voltage drops current must increase to maintain power supplied, causing system to consume more reactive power and the voltage drops further . If the current increase too much, transmission lines go off line, overloading other lines and potentially causing cascading failures.
If the voltage drops too low, some generators will disconnect automatically to protect themselves. Voltage collapse occurs when an increase in load or less generation or transmission facilities causes dropping voltage, which causes a further reduction in reactive power from capacitor and line charging, and still there further voltage reductions. If voltage reduction continues, these will cause additional elements to trip, leading further reduction in voltage and loss of the load. The result in these entire progressive and uncontrollable declines in voltage is that the system unable to provide the reactive power required supplying the reactive power demands.
Important information
1)The control relay should be disconnected from the mains during installation.The reactive power control relay is designed for voltage supplies of up to 240VAC.
2)The connections for the supply voltage are to be fused externally with 4A max.
3)In the case of mains networks that do not facilitate voltage tapping in the 220VAC to 240VAC range (either phase/phase or phase/neutral), a voltage transformer must be used for the power supply for the control relay.
4)The nominal voltage between the ”Meas” and ”N” connectors may not exceed 240 VAC. The voltage between the ”Meas” and ”L” connectors may not exceed 420 VAC.
5)If ”Meas” is connected directly to a phase conductor, then this is to be secured externally with a maximum of 4 A.
6)The control relay should be disconnected from the mains during installation.
7)The nominal voltage between the”Meas” and ”N” connectors may not exceed 240 VAC. The voltage between the ”Meas” and ”L” connectors may not exceed 420 VAC.
8)If ”Meas” is connected directly to a phase conductor, then this is to be secured externally with a maximum of 4 A.
9)The outputs of the switching contacts do not have floating potential.
Caution:-
The nominal current in the current transformer path may not exceed 5 A.