Adaptive Current Differential Protection Schemes for Transmission-Line Protection

Abstract

Abstract-Throughout the history of power system protection, researchers have strived to increase sensitivity and speed of apparatus protection systems without compromising security. With the significant technological advances in wide-area measurement systems, for transmission system protection, current differential protection scheme outscores alternatives like overcurrent and distance protection schemes. Therefore, in this paper, we address this challenge by proposing a methodology for adaptive control of the restraining region in a current differential plane. First an error analysis of conventional phasor approach for current differential protection is provided using the concept of dynamic phasor. Subsequently, we extend the methodology for protection of series compensated transmission lines. Finally, we also evaluate the speed versus accuracy conflict using phasorlets. Electromagnetic Transient Program simulations are used to substantiate the claims. The results demonstrate the utility of the proposed approach.

Instantaneous protection scheme for backup protection of high-voltage transmission lines

“…The philosophy of unit protection is related to Kirchhoff's current law, which states that the value of current leaving a circuit must be equal to the value of that entering the circuit. Current differential protection is also immune to the power swing phenomenon, which causes the protection to be more stable and reliable during mass changing of the load flow in the system [9]. For a fault within its zone of protection, a relay will instantaneously operate the scheme in order to isolate the fault through the dedicated circuit breaker.…”

Protection of AC and DC distribution systems Embedding distributed energy resources: A comparative review and analysis

“…However, due to the requirement for the infrastructure of communication links, this method is not economic solution for some types of small distribution system. It is noted that a synchronizing mechanism may also be needed in case the line is long [69].…”

Reliability Analysis Models for Differential Protection Considering Communication Delays and Errors

“…(1) The action criterion of the current differential protection Currently, the following two criteria are commonly used for the activation of transmission line phase current differential protection [5,22]: Start criterion: Icd ≥ Iop, Icd is the differential current; Iop is a constant determined offline. The threshold of the relay protection is Imax:…”