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.
- Active power is the energy supplied to run a motor, heat a home, or illuminate an electric light bulb. Reactive power provides the important function of regulating voltage.
- If voltage on the system is not high enough, active power cannot be supplied.
- Reactive power is used to provide the voltage levels necessary for active power to do useful work.
- Reactive power is essential to move active power through the transmission and distribution system to the customer .Reactive power is required to maintain the voltage to deliver active power (watts) through transmission lines.
- Motor loads and other loads require reactive power to convert the flow of electrons into useful work.
- When there is not enough reactive power, the voltage sags down and it is not possible to push the power demanded by loads through the lines.”
Why Do We Need Reactive Power?
- Reactive power (VARS) is required to maintain the voltage to deliver active power (watts) through transmission lines.
- Motor loads and other loads require reactive power to convert the flow of electrons into useful work.
- When there is not enough reactive power, the voltage sags down and it is not possible to push the power demanded by loads through the lines.