Quality monitoring of electrical power to evaluate the operational reliability of power equipment and active–adaptive voltage control in distribution power grids

Abstract

Monitoring systems of power quality and operation mode parameters are currently being developed and widely introduced. These systems make it possible to receive needed information in different nodes of a grid in real time, as well as build up data archives over a long period of time. The presence of such information makes it possible to change the approach to short- and long-term control by distribution grids. This paper describes the possibilities of application of information obtained from a monitoring system to control distribution power grids using the example of reliability evaluation of power equipment to schedule the repairs, and active–adaptive voltage control system. The dependences are shown of probability of failure of power equipment on operation time under different types of load curves and power quality. The conclusion is drawn that the wear of main equipment significantly increases when it is operated in conditions of low power quality. The dependence is shown of changing repair and inspection frequency of equipment on operation time and operating conditions. This paper describes the structure and principles of operation of an active–adaptive voltage control system. As a test example, the amount of violations upon steady-state voltage deviations of power consumers in a distributed grid using different methods of voltage control in a power supply center are compared. It is shown that, at nonuniform load in the grid, the required voltage level cannot be provided by the counterload regulation method. The ease of use of a monitoring system of the power quality of operation mode parameters of power consumers makes it possible to use the control system providing a required voltage level for the greatest number of power consumers.