Optimal Power Flow Control Based On Electronic Power Transformer

Using kinds of power electronic devices and system to control power flow is one of the most important ways to make power system safe, stable, economic and effective. Both FACTS and HVDC is the international hot research field in the power electronic technology applied in power system. However, neither HVDC nor FACTS exists flow. EPT is a new intelligent transformer. Compared with normal FACTS devices, EPT can provide stronger control ability and more flexible control mode. Despite the functions of regular OLTC on transformation, isolation and energy transmission, EPT can also generate and absorb reactive power, and accommodate active power of the branch at the same time.EPT is equal to two open PQ nodes, PV nodes or balance nodes when it is used in power system to optimize the power flow, the outputs of the genetic algorithm (GA) are reactive power and active power in the EPT's primary side and secondary side. By controlling reactive power, EPT can optimize reactive power, improve power quality and reduce power loss. While accommodating reactive power, EPTs can control the active power flowing among them so that power flow will be more suitable and power system will be more stable.This dissertation mainly studied reactive power optimization in distribution system and power flow optimization in transmission system based on EPT. Simulation results show that instead of OLTC, EPT can optimize power flow, decrease the reactive power compensation devices, reduce power loss efficiently and improve power quality and stability. With the number of EPT increasing, the optimization is more effective.EPT can work with no limitation of times, so it is more effective in the optimization of dynamic power flow...