Importance of Reactive Power in Electrical Power Transmission Systems
• Introduction:-
Power is classified into two main types in electrical systems:-
• Active power (real power): The energy consumed by the load and converted into useful work.
• Reactive power: –
Although it doesn’t perform useful work, it is essential and cannot be neglected.
• Definition of Reactive Power: –
Reactive power is stored in magnetic fields in inductors or electric fields in capacitors. It doesn’t convert into useful energy but is crucial for the system. Real power often relies on the existence of reactive power.
• How Generators Produce Reactive Power:-
Generators manage reactive power by adjusting their excitation current. Increasing the current produces more reactive power, while reducing it causes the generator to absorb reactive power. This helps maintain voltage levels across the network.
• Importance in Transformers: –
Reactive power is essential for transformers to operate, as they rely on electromagnetic induction. This is why DC transformers don’t exist.
• Importance in Transmission Lines: –
Transmission lines produce reactive power through self-capacitance, and they absorb reactive power to generate magnetic fields through self-inductance.
• Balancing Reactive Power:-
If the reactive power produced equals the amount absorbed, the voltage remains stable along the line without any drop.
• Reactive Power Imbalance:-
• Decrease in Reactive Power:–
Leads to a voltage drop and lower power factor, necessitating capacitor banks.
• Excess Reactive Power: –
Increases the voltage, which is also undesirable.
• Conclusion: –
Reactive power is essential for system stability and voltage management, highlighting the need for calculating Surge Line Impedance (SIL).