How is Apparent Power (MVA) mathematically expressed?

The correct expression for Apparent Power (measured in MVA) is derived from the relationship between real power (MW), reactive power (MVAR), and apparent power. Apparent Power is a combination of both real power and reactive power, and it is defined using the Pythagorean theorem in the context of electrical power.

In the context of alternating current (AC) circuits, the relationship can be represented as follows:

Apparent Power (S in MVA) is the vector sum of Real Power (P in MW) and Reactive Power (Q in MVAR). This can be mathematically expressed as:

S² = P² + Q²

Reforming this gives:

MVA² = MW² + MVAR²

This relationship highlights that the square of apparent power is equal to the sum of the squares of real power and reactive power, thereby reflecting the inherent nature of these powers in AC systems.

This definition clarifies that Apparent Power encompasses both the active and reactive components of power in a system, confirming its importance in defining the overall power in electrical engineering.