RESEARCH SWITCHING OVERVOLTAGES IN LOW VOLTAGE NETWORKS IN VIET NAM AND PROPOSED LIMITED SOLUTIONS

Abstract

Overvoltage is one of the main causes of serious problems in the power
system, overvoltage may appear due to lightning strikes or switching off in the
power network. This paper presents the results of research on the effect of
switching overvoltage in low voltage network and proposes some solutions to
limit overvoltage. The voltage amplitude and shape of the overvoltage were are
determined to evaluate the effect on the equipment used. In addition, the TRV
(transient recovery voltage) and the rate of rise of recovery voltage (RRRV) are
also determined for the purpose of designing, manufacturing and operating of
the switchgear safely and economically. This is an issue that is urgently needed
by manufacturers of switchgear applications in power systems. The results of
comparing the overvoltage values before and after using the solutions are
compared and evaluated. The research results are based on the theory of the
transitional process and EMPT/ATP software.