Impact of controllable superconducting series reactor in transient recovery voltage of circuit breaker

Due to the development of modern grids and the extensive implementation of distributed generators, the fault current level increases, which affects the operation of circuit breakers.

byAmir Heidary, Hassan Moradi Cheshmebeigi, Ali Mehrizi-Sani

54 Impact of controllable superconducting series reactor in transient recovery voltage of circut breaker
  1. Introduction

Due to the development of modern grids and the extensive implementation of distributed generators, the fault current level increases, which affects the operation of circuit breakers (CB) [1]. Transient recovery voltage (TRV)is a concern that can damage a CB [2]. Saving a CB from failure needs special attention to both current fault level and TRV factors based on IEEE Std C37.119-2016 [3].

The most common solution to protect the CB from fault current is either magnetic-based [4] or resistive-based [5]-[7] superconducting fault current limiters. Among different types of superconducting fault current limiters (SFCL). Among types of superconducting FCLs, the inductive SFCL is a piece of protection equipment that limits the fault current by imposing inductance to faulty lines [8]-[9]. Its inductance is very low in the normal state of the power system [10]. An SFCL can be very useful for protecting the CB from raising the fault current level [11].

 

The next important matter for CB operation is the occurrence of the CB terminal TRV. This phenomenon depends on equivalent inductance, resistance, and capacitance of the faulty system [12]. Moreover, the inductance of a faulty electric system with the presence of SFCL increases, which affects the factors of TRV as the peak of TRV, frequency, rate of raising recovery voltage (RRRV), and TRV damping constant [13].

In this paper, TRV of CB is investigated, whereas SFCL is not employed. Then, the TRV of the circuit breaker is discussed, considering the inductive SFCL in series with the faulty line. Next, the behavior of the controllable superconducting series reactor (CSSR) as a TRV reduction circuit is described. It is shown that not only is this topology able to limit the magnitude of TRV, but it also can protect the CB from the sharp raising of recovery voltage. The contributions of this work are as follows:

  • an overview of the inductive SFCL effect in TRV of a circuit breaker
  • effect of a CSSR in TRV of a circuit breaker
  • finite element based magnetic field analysis and transient simulation of the proposed CSSR
To read the article, subscribe and choose the option which suits you best. We offer both free and paid options, and the registration takes only a minute.
Subscribe to Transformers Magazine