In an over-capacitive system, what effect does a leading current sine wave have on voltage?

• A. Decrease load
• B. Raise
• C. No effect
• D. Lower

Answer: (B)

In an over-capacitive system, a leading current sine wave indicates that the current phase angle is ahead of the voltage phase angle. This situation typically occurs when the reactive power from capacitors in the system exceeds the reactive power demand from inductive loads. As a result, the excess reactive power can lead to an increase in voltage levels throughout the system.

When the current is leading, it pulls the voltage upward. This phenomenon is due to the capacitive nature of the load, where the capacitive reactance helps in raising the voltage by supplying reactive power to the system. In essence, the excess leading current injected into the system from capacitive devices will cause the overall voltage to rise, which can potentially lead to overvoltage conditions if not managed properly.

Thus, the effect of a leading current sine wave in an over-capacitive system is an increase in voltage, making the correct answer the option indicating that it raises voltage.