A Pilot Protection for HVDC Transmission Lines Based on Transient Energy Ratio of DC Filter Link

Single‐end protection algorithm for HVDC transmission lines based on the current difference

“…The maximum detectable fault resistance of the proposed algorithm is also higher compared to the methods in [8–11, 17, 18, 24–26]. The sampling frequency of the proposed algorithm is higher than the methods in [17, 18, 25], is equal to [22] and is less than [8–11, 14–16, 19–21, 23, 24, 26]. Compared to the methods in [22, 26], the proposed algorithm needs a shorter data window.…”

“…In summary and according to Table 7, the proposed protection algorithm is faster than the methods presented in [8, 14, 16, 21–26]. This is because these protections need more samples and processing time to extract harmonics and high‐frequency components required to discriminate between internal and external faults.…”

“…In [15], the capacitive effect is calculated in the time domain using the transmission line distributed parameter model. A protection scheme based on the ratio of transient energy within a specific frequency band on both sides of the line boundary is proposed in [16] to overcome shortcomings of the traditional current differential protection for HVDC transmission lines. A protection scheme based on transient energy measured at both ends of the DC line is proposed in [17].…”

“…A protection method using transient power at both ends of the DC line is presented in [18]. The methods in [14–18] are not highly reliable due to the requirement of the communication link. Moreover, the fault resistance effect is not addressed in [18].…”

Current differential relay characteristic for bipolar HVDC transmission line fault detection

“…However, both voltage and current data at both line ends are required, and its performance is highly dependent on the line parameters during the fault transient period. In [13], a pilot protection scheme has been proposed for LCC‐HVDC bipolar transmission lines based on the transient energy ratio of the DC filter link. This scheme has a faster tripping speed than those in [7–12].…”