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___________________┬аis needed to establish the magnetic and electrostatic fields; it is temporarily stored and then released
Active Power
Reactive Power
Instantaneous Power
Apparent Power
Reactive Power
Reactive Power (Q) represents the portion of electrical power that oscillates back and forth between the source and the load. It is essential for sustaining the magnetic fields in inductive components and electrostatic fields in capacitive components, without performing any net useful work.
Reactive Power (Q) represents the portion of electrical power that oscillates back and forth between the source and the load. It is essential for sustaining the magnetic fields in inductive components and electrostatic fields in capacitive components, without performing any net useful work.
Q=VIsin(╧Х) тАФ Instantaneous Reactive Power in terms of voltage and current phase difference
Q=I2X тАФ Reactive power consumed by an inductive reactance X
In an AC system, inductive loads (like motors and transformers) absorb reactive power to build magnetic fields during the positive half-cycle and release it during the negative half-cycle. Similarly, capacitive loads (like capacitors) store energy in electrostatic fields. Because this energy cycles at twice the system frequency, it does not contribute to real power dissipation but is necessary to maintain the voltage levels required for energy transmission.
Measured in Volt-Amperes Reactive (VAR).
Does not result in heat or mechanical work (Real power P does).
High reactive power leads to poor power factor, increasing I2R losses in transmission lines.
Inductors have positive Q (consuming); capacitors have negative Q (generating/supplying).
Necessary for the operation of induction motors and transformers.
Used to control system voltage profiles by compensating for line drops.
Increases current magnitude without contributing to work, causing higher conduction losses.
Reduces the effective capacity of power lines and transformers.
Shunt capacitors for voltage support.
STATCOMs and SVCs (FACTS devices) for dynamic reactive power compensation.
Option A (Active Power) performs useful work; Option C (Instantaneous Power) is the product of instantaneous voltage and current; Option D (Apparent Power) is the vector sum S=P2+Q2тАЛ.
B is correct тАФ Reactive power is the quantity of power that fluctuates between source and load to maintain magnetic and electric fields.
Always remember that inductive loads 'consume' reactive power while capacitive loads 'generate' reactive power; this principle is the foundation for voltage stability in power grids.