风电/光伏/制氢/超级电容器并网系统建模与控制

Modeling and Control of Grid-Connected System of Wind/PV/Electrolyzer and SC

针对风机与光伏发电功率波动、弃光等问题,提出风电/光伏/制氢/超级电容器并网系统模型及控制策略。建立风机、光伏、电解槽及超级电容器数学模型,构造一种变流器少、占地面积小、成本低的光伏、电解槽和超级电容器集结于直流母线结构。协调控制策略如下:当风电与光伏总出力大于负荷需求且功率差额小于电解槽额定功率时,电解槽消纳系统剩余功率;当负荷需求突降时,电解槽运行于额定状态,超级电容器快速充电,平抑直流母线电压波动,待到其端电压达到充电深度电压时,退出运行;当冲击性负荷扰动电网时,电解槽处于停机状态,超级电容器快速放电,平抑直流母线电压波动,待其达到放电深度电压时,退出运行。通过仿真,验证了风电/光伏/制氢/超级电容器并网系统模型与控制策略准确性及有效性。

Aiming at intermittency of photovoltaic（PV） and wind power output, model and control strategy of hybrid wind power/PV/hydrogen production system is proposed in this paper. A model of wind power, PV, electrolyzer（EL） and supercapacitors（SC） is built up. Adopting structure of PV, EL and SC connected to DC-bus leads to reducing converter number, saving space and cost. When output of wind power and PV is slightly greater than load demand but power difference is less than EL rated power, EL will accommodate remaining power of the system. When load demand drops abruptly, EL runs at its normal ratings, and SC charges rapidly, contributing to stabilizing DC-bus voltage. However, when SC terminal voltage reaches to depth voltage of charging, it will withdraw from service. When impact load disturbs grid, EL will be shut down. In the same time, SC discharges quickly to stabilize DC bus voltage. Nevertheless, it will withdraw from service when SC terminal voltage reaches depth voltage of discharging. With the strategy, PV efficiency is improved and system power quality is optimized. Simulation results show that the model and control strategy of hybrid wind power/PV/El/SC system are effective.