Principle and Control Design of a Novel Hybrid Arc Suppression Device in Distribution Networks

Abstract

A single line-to-ground (SLG) fault may lead to a more severe line-to-line fault and power supply interruption if the ground-fault current exceeds a certain value. Arc suppression device (ASD) is a good solution to eliminate the ground-fault current. A novel hybrid ASD is proposed in this paper, which consists of a passive device and an active one. The passive device utilizes multi-terminal breakers and an isolation transformer to couple a secondary voltage of a Zig-Zag grounding transformer to the neutral point to compensate the majority of the ground-fault current. The active device uses a single-phase voltage source inverter to eliminate the residual fault current due to the leakage inductance of the Zig-Zag grounding transformer in the passive device. A dual-loop voltage and current control method for the active device is designed for the accurate residual current compensation. Results of simulation and prototype experiment validate the effectiveness of the proposed hybrid ASD. The proposed hybrid ASD does not need to detect distributed line-to-ground parameters, and it has lower cost, less control complexity, higher reliability, and better performance, compared to other ASDs.

A novel single‐phase grounding fault voltage full compensation topology based on antiphase transformer

“…Note that, when a single-phase grounding fault occurs, the ASC and the proposed topology are immediately activated, so that the fault voltage can be well compensated, and the distribution system can be allowed to operate during the faulty period for 1-2 h, so the circuit breaker will not be tripped immediately [3,[10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. After a certain delay, the phase selection switch of the proposed topology trips.…”

Faulty Phase Detection Method Under Single-Line-to-Ground Fault Considering Distributed Parameters Asymmetry and Line Impedance in Distribution Networks

“…Considering the range of the distribution network parameters, by using the method of enlarging and reducing on (12), it is reasonable that M 1 M 2 >0. Therefore, U B increases after the fault.…”

“…The corresponding methods can be characterized to current and voltage method according to the control objectives, i.e., output current or voltage of the devices [8]- [10]. For the voltage method, the accurate recognition of the faulty phase under SLG fault is the basis for successful arc suppression [11], [12]. If the faulty phase is incorrectly identified, the voltage method expands the fault to two-phaseto-ground fault, resulting in trip of the feeder line and further unnecessarily power cut [13], [14].…”

Active arc suppression device based on voltage‐source convertor with consideration of line impedance in distribution networks

“…As the bolted ground fault rarely happens, the ground‐fault resistance R f is chosen to be 10 Ω to 10 kΩ in case study [14]. Thus, the power stage of the distribution network is in fundamental frequency, in which the distribution network can be treated as series connected voltage source E 0 and zero‐sequence impedance of the distribution network Z 0 , expressed in [15], where R 0 , C 0 are set as the symmetric phase‐to‐ground parameters of three‐phase, Z eq is the line impedance.…”

“…In literature [13,14], the zero-sequence voltage controlled by the ASD is adjusted to be the negative of the fault phase voltage, which constrains the recovery voltage at the fault point to zero, so as to achieve fault arc suppression. A hybrid flexible grounding system, which combines a large-capacity reactive power reactor with an active power compensator for ground current compensation is mentioned in [15]. Most ASD methods can obtain satisfying grounding fault current compensation.…”