Reactive Power is a Byproduct of Alternating Current (AC) Systems. Transformers and transmission lines introduce inductance as well as resistance: Both oppose the flow of current. Must raise the voltage higher to push the power through the inductance of the lines.
How is reactive power generated?
Reactive power is either generated or absorbed by electric generators (or, in some cases, devices known as “capacitors”) to maintain a constant voltage level, commonly referred to as providing “voltage support.” Generators providing voltage support often suffer heating losses that result in a reduced ability to …
Do transmission lines absorb reactive power?
Transmission lines supply reactive power to the system when lightly loaded but absorb reactive power when heavily loaded. These results are for a 100-mile line with voltages supported at both ends. Voltage control is accomplished by managing reactive power on an alternating-current power system.
How the reactive power flow is controlled in power transmission?
The reactive power in the transmission lines can be controlled by controlling the firing angle of the thyristors. In the system, the TCR introduces the harmonic current. The harmonics in current can be brought within the particular limit by managing the reactive power injection.
How does reactive power flow?
Reactive power flows from the source to the sinks. It flows back and forth from source and sink without doing any real work. The reactive power in a power system is associated with the electric field and the magnetic fields of the power systems.
What is reactive power in transmission line?
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.
Why is reactive power generated?
Devices which store energy by virtue of a magnetic field produced by a flow of current are said to absorb reactive power; those which store energy by virtue of electric fields are said to generate reactive power. The flows of Reactive Power on the system will affect Voltage levels.
How do you control reactive power?
Industrial consumers are normally charged for reactive as well as active power; this gives them an incentive to improve the load power factor by using shunt capacitors. Compensating devices are usually added to supply or absorb reactive power and thereby control the reactive power balance in a desired manner.
How do you fix reactive power?
In principle the solution of the reactive power problem is obvious: it is to install additional inductance or capacitance as required to alleviate the supply of the need to handle the reactive power. This is the general principle of power factor correction.
Do we pay for reactive power?
Simply put, if the Reactive Power consumption is more, the effective power factor reduces and there is a higher voltage drop across the line and teh total power transmitted also increases which needs to be supplied for by the Power Source. To compensate for this, we pay for reactive power.
How does power flow in a transmission line?
For R ≈ 0 (which is a valid approximation for a transmission line) the real power transferred to the receiving-end is proportional to sin δ ( ≈ δ for small values of δ ), while the reactive power is proportional to the magnitude of the voltage drop across the line.
How do you calculate reactive power in a transmission line?
Calculating the real and reactive power of a transmission line
- Sending end power = 3.75MW.
- RL=5.18 ohms.
- XL=130 ohms.
- VS (Generator bus)=161kV.
- VR (Infinite bus)=161kV.
- Sending end voltage angle (delta) = 0.01877 (Angle which allows 3.75MW to be transferred)