Coordinated voltage regulation strategy of OLTC and BESS considering switching delay

When large-scale distributed renewable energy power generation systems are connected to the power grid,the risk of grid voltage fluctuations and exceeding the limit increases greatly.Fortunately,the on-load tap changer(OLTC)can adjust the transformer winding tap to maintain the secondary side voltage within the normal range.However,the inevitable delay in switching transformer taps makes it difficult to respond quickly to voltage fluctuations.Moreover,switching the transformer taps frequently will decrease the service life of OLTC.In order to solve this critical issue,a cooperative voltage regulation strategy applied between the battery energy storage systems(BESSs)and OLTSs.is proposed By adjusting the charge and discharge power of BESSs,the OLTC can frequently switch the transformer taps to achieve rapid voltage regulation.The effectiveness of the proposed coordinated regulation strategy is verified in the IEEE 33 node distribution systems.The simulation results show that the proposed coordinated regulation strategy can stabilize the voltage of the distribution network within a normal range and reduce the frequency of tap switching,as such elongating the service life of the equipment.

电池储能系统参与配电网电压调节的策略研究

以可再生能源为核心的分布式发电(Distributed Generation,DG)易受天气、季节、气候等条件的影响,具有间歇性、随机性发电的特点。当大规模接入配电网后会影响电能的质量,降低电网的稳定性,从而会使电网电压产生波动。针对传统的电压调节方法存在的不足,提出了一种利用电池储能系统(Battery Energy Storage Systems,BESSs)来进行电网电压调节的策略,对电网电压进行调节的同时,对电池的电荷状态(State of Charge,SOC)也进行实时监控,避免电池在充放电时发生过充过放。

计及用户端调节容量的变频空调自适应电压调控策略

随着分布式新能源的高比例接入以及电动汽车的普及,配电网过电压、欠电压、电压波动等电压质量问题与日俱增。变频空调作为一种常见的柔性负荷,可以改变自身的运行功率为配电网提供电压调节服务,提高配电网的电压质量。然而,利用用户侧资源为配电网提供电压调节服务需要考虑用户侧资源的电压调节容量,为此,提出了一种计及用户端调节容量的变频空调自适应电压调控策略,通过逐步计算各个节点的电压调节功率来控制补偿功率,并建立空调的热电等效模型描述房间热动态变化,评估空调电压调节潜力。为了验证所提出的调控策略的有效性,计及用户端调节容量的变频空调自适应电压调控策略将用于IEEE 33节点配电系统进行配电网电压优化仿真,仿真结果证明所提出的计及用户端调节容量的变频空调自适应电压调控策略,能够保证配电网电压不越限的前提下,减少调节所需的补偿功率,并充分发挥空调的电压调节潜力。