Research on Distributed Harmonic Mitigation Strategy for HVDC Systems Based on Optimal Configuration of Active Filters

In recent years, numerous high-voltage direct current (HVDC) systems are observed severe low-order harmonics on the AC side. The common solution is installing passive filters. However, it may introduce new resonance issues. With the widespread application of power electronic devices in high-voltage scenarios, active filters are employed to mitigate harmonic in HVDC systems. In addition, there are multiple harmonic sources near the HVDC station, single point harmonic mitigation is difficult to completely solve this problem. Therefore, this paper proposes a distributed harmonic mitigation strategy and establishes an optimized configuration model for active filters. Besides, an improved particle swarm optimization (PSO) algorithm to optimal determination of the number, location, and capacity of active filter installations for harmonic mitigation. Finally, this paper takes the harmonic problem of an actual HVDC system in China as an example to verify the effectiveness of the proposed distributed harmonic mitigation strategy.