含直流馈线分区优化的交直流混合微电网规划

AC/DC Hybrid Microgrid Planning with Optimal Placement of DC Feeders

随着直流负载和电源设备的不断发展,传统交流电网需要承担的直流负载容量也不断增加。这将导致整流逆变器装置等电力电子设备的大量接入影响电网的稳定性与经济型,而交直流混合微电网可作为这一问题的良好解决方案,在满足交流和直流负载供电的同时,减少整流逆变装置的安装数量。由于直流负载可在微电网中随机分布,如何布置直流馈线同时又能满足微电网运行的经济性和安全性指标,仍需进一步研究。为了解决这一问题,以分布式电源、整流逆变装置和交直流混合配电网的投资总成本以及DERs的运行费用最小为目标,提出了含直流馈线分区优化的交直流混合微电网规划模型。还针对交直流混合微电网的潮流方程进行统一推导,并纳入规划模型当中。提出的模型能够在保证直流馈线连续性的前提下,实现DERs的选址定容优化以及直流馈线分区优化。在改进IEEE-33配电系统中对模型进行了测试,实验结果验证了模型的有效性。

With the continuous development of DC load and power supply equipment,the capacity of DC load borne by traditional AC power grid is also increasing.Subsequently,a large number of rectifier-inverter devices and other power electronic devices are installed in power grid,leading to the decline in the stability and economy of the grid.AC/DC hybrid microgrid can be used as an effective method of solving this problem,and can satisfy the requirements of AC and DC loads while reducing the demand of rectifier-inverter device installation.Due to DC loads can be randomly distributed in the microgrid,how to arrange the DC feeder and meet the economic and safety indexes of the microgrid operation still requires further research.To address this problem,the paper proposes an AC/DC hybrid microgrid planning model with the optimal placement of DC feeders,with the objective of minimizing the total investment cost of the distributed energy resources(DERs),rectifier-inverter devices and AC/DC hybrid distribution network as well as the cost of the operation of DERs.In addition to this,the power flow equation of the AC/DC hybrid microgrid is derived uniformly and is incorporated into the planning model.Therefore,the proposed model can optimize the placement of the DC feeders and the planning for DERs locating and sizing under the premise of the continuity of the DC feeder placement.The effectiveness of the proposed model is validated by the test results in improved IEEE 33-bus distribution system.