Research and development of 500kV hybrid HVDC circuit breaker with current commutation drive circuit

Quantitative criteria of considering AC infeed in DC fault assessment of modular multilevel converters

“…7, the DC fault current reaches 12.3 kA in 10 ms after the DC fault. An engineering prototype of 500kV DCCB has been developed, and the experimental verification of ± 25kA fault current interrupting has been completed [9,27]. Thus, the DCCB is able to interrupt the DC fault current within 10 ms without blocking the MMC.…”

“…However, the method of blocking IGBTs fully disables the controllability of the converter, interrupts the power transmission, and prolongs the outage duration of the HVDC system. Currently, DC circuit breakers (DCCBs) [9][10][11] have been proposed to deal with DC faults without blocking the MMC, which is beneficial for continuous operation of the HVDC grid. The selection of the DCCB should ensure that the fault current is less than the DCCB capacity.…”

HVdc Circuit Breakers: Prospects and Challenges

“…This breaker clears the 5 kA fault current within a fault clearing time of 60-100 ms [90]. However, the development of semiconductor technology has reduced the attraction of electromechanical breakers for short circuit faults in multi-terminal HVdc systems [91].…”

Research on Overvoltage Suppression by Blocking Diode and DC Circuit Breaker in LCC-VSC Hybrid HVDC System

“…There would be no cycle zero-crossing point for the DC current relative to the AC, so the structure and principle of the DC circuit breaker could be completely inconsistent with the AC circuit breaker, and the cost could be significantly higher than that of the AC circuit breaker. There have been two main types of common DC circuit breakers, i.e., mechanical and hybrid [21]. A mechanical DC breaker could use an auxiliary zero-return circuit to generate a DC current cut off after the current passed zero, and then it could use the energy-consuming circuit to consume the voltage-current shock wave during the oscillation.…”

“…With the emergence of the multi-terminal DC transmission technology, the design and application of DC circuit breakers have been significantly progressed [20]. Literature [21] presented the key technologies of the DC circuit breaker with the commutation drive circuit from four aspects (I.e., topology, fast mechanical switch, power electronics and com-mutation principle). Literature [22] used a capacitor to force the fault current to zero by using the reverse current injection method.…”