Methods to Minimize Zero-Missing Phenomenon

Abstract

With the increasing use of high-voltage AC cables at transmission levels, phenomena such as current zero-missing start to appear more often in transmission systems. Zero-missing phenomenon can occur when energizing cable lines with shunt reactors. This may considerably delay the opening of the circuit breaker, leaving the system unprotected and vulnerable to failures. Methods to prevent zero-missing phenomenon are still being studied and compared in order to identify effective countermeasures. This paper contributes to these efforts, by presenting several countermeasures that can be applied to reduce the hazards of zero-missing phenomenon. The authors discovered that this phenomenon can be eliminated, merely by using an extra circuit breaker or a preinsertion resistor.

Countermeasures of Zero-Missing Phenomenon in (E)HV Cable Systems

“…However, an additional cost for the purchase of an extra breaker/disconnector and the resistor is imposed. Reference [5] has proposed an iterative process to solve differential equations for calculation of the pre-insertion resistor value. A formula based on energy equations (energy that the pre-insertion resistor should dissipate) is also proposed in [4] and [5].…”

“…In [4], authors studied the use of pre-insertion resistors to minimize the zero-missing current, where they proposed a simple formula to approximate the resistor value. The expanded version of [4] is presented in [5], where some extra countermeasures of the zero-missing phenomenon are also discussed. An iterative process for more accurate calculation of the pre-insertion resistor size is provided in [5].…”

“…The expanded version of [4] is presented in [5], where some extra countermeasures of the zero-missing phenomenon are also discussed. An iterative process for more accurate calculation of the pre-insertion resistor size is provided in [5]. In [6], a general overview of the countermeasures and a more detailed study of the sequential switching countermeasure are provided.…”

Shunt compensation design of EHV double-circuit mixed OHL-cable connections

“…Reactive power compensation by means of shunt reactors (SRs) has to be applied for long EHV cables to consume reactive power surplus of cable and to keep system voltage within acceptable margins. It is crucial to have sufficient size of shunt compensation because both undercompensation and overcompensation can lead to undesirable system operation like overvoltage (and generator self-excitation in extreme situations) and zero-missing phenomenon, respectively [3,8].…”

Wideband Modeling, Field Measurement, and Simulation of a 420-kV Variable Shunt Reactor

“…The switching in and out of shunt reactors by circuit breaker operation leads to transient phenomena which can disturb the system operation. For instance, energizing a cable having near 100% shunt compensation at its ends can lead to current zero-missing phenomena [1] which can temporarily prevent the circuit breaker from disconnecting the cable during a fault. Shunt reactor disconnection leads to a transient recovery voltage (TRV) across the circuit breaker contacts of a frequency of typically 1-5 kHz and a peak value which is strongly dependent on the circuit breaker chopping current [2], [3].…”