Control the voltage instabilities of distribution lines using capacitive reactive power

The voltage instabilities in the distribution lines are primarily related to the integration of photovoltaic power plants with the local grids. Conventional tap-changers cannot compensate for the rapid disparities between generated and consumed power because of sluggish dynamic response. This article presents an effective method and control algorithm to improve the voltage instabilities of distribution lines. Analytical calculation confirms that the application of capacitive reactive power on load is beneficial to keep the voltage at the permissible level. Importantly, the severe concern about the current increment with voltage enhancement is also addressed. The dynamic behavior during capacitance switching is studied using simulation experiments. It is suggested that capacitance is connected to the load for the only time of voltage drop until the transformation ratio changes to the desired level. This article provides an explanation and solution for voltage deviations of electricity distribution lines in steady-state and dynamic modes.