What is the risk of excessive MVAR supply during restoration attempts?

• A. Increased line losses
• B. Potential for equipment overloads
• C. Triggering further voltage drops
• D. Complications with system stability

Answer: (D)

The risk of excessive MVAR (megavolt-ampere reactive) supply during restoration attempts can indeed lead to complications with system stability. When there is too much reactive power being injected into the system, it can disrupt the balance between voltage levels and reactive power. This imbalance can result in overly high voltage conditions, which may cause equipment and system instability, leading to undesirable oscillations or even system failure.

Restoration attempts in power systems require precise control of voltage and reactive power to ensure that stability is maintained as loads are gradually added back to the system. If MVAR supply is excessive, it can create a scenario where voltage levels fluctuate significantly, adversely affecting the reliability and operational integrity of the system during restoration.

While the other options touch on valid concerns, such as losses, overloads, and voltage drops, the main issue with excessive MVAR during restoration focuses on its direct influence on the stability of the system, which can have cascading effects on overall grid reliability.