混合型背靠背智能软开关技术

基于背靠背电力变换器的智能软开关(SOP)能柔性、快速、精确调控配网潮流,实现配网电压、网损等多控制目标统一优化管理,同时具备故障隔离和故障恢复功能。但该型SOP的供电恢复范围受限于其自身容量,难以满足全部停电用户供电需求。文中提出了一种由小功率背靠背电力变换器与负荷开关并联组成的低成本混合型SOP。正常工作模式下,仅由背靠背电力变换器调控系统潮流及电压分布;线路故障模式下,由负荷开关承担供电恢复功能,且故障清除后通过灵活调控背靠背电力变换器实现闭环运行工况下负荷开关的零电流开断,增加负荷开关使用寿命,降低成本。最后,通过仿真验证了混合型SOP的供电恢复能力以及零电流开断技术的有效性和可行性。

Technology of hybrid back-to-back soft open point

The soft open point (SOP) using the back to back power converter can flexibly, fast and accurately regulate the power flow among the adjacent feeders by implementing the multi-targets control including nodes voltages and network losses and also has the capability to isolate the fault and recover the power supply. However, the range of power restoration is strictly limited by the SOP capacity. A hybrid soft open point system with a partial scale back to back converter and a load switch parallel connected is proposed. The power flow and voltage distribution could be regulated by the back to back converter as usual. And the load switch could realize power recovery for all the customer interruption under the fault condition. Moreover, the back to back converter can flexibly regulate the power flow through the load switch and help realize the zero current turning off of the load switch, which can effectively extend the working life of the load switch and reduce the equipment cost. Furthermore, the performance of the proposed hybrid SOP is verified by the simulation results.