If the voltage at substation A is higher than at substation B, how is the reactive power (MVAR) flow indicated?

When analyzing reactive power flow in an electrical system, it is essential to understand that reactive power, measured in megavolt-amperes reactive (MVAR), flows in response to voltage differences across substations. If the voltage at substation A is higher than at substation B, the flow of reactive power occurs from the higher voltage point (substation A) to the lower voltage point (substation B).

This behavior aligns with the principles of electrical power systems, where reactive power is drawn into systems where the voltage is lower. In this case, because substation A has a higher voltage, it is providing reactive power to substation B, facilitating voltage support in the lower voltage area.

Therefore, the reactive power flows from substation A to substation B, indicating that electrical systems work to maintain voltage stability by enabling the flow of reactive power towards areas of lower potential to mitigate voltage drops. This dynamic is crucial for the proper functioning of power systems, ensuring they remain stable and reliable in their operation.