一种级联固态变压器整流级均压控制策略研究

A Novel DC-Link Voltage Balancing Control Strategy for Modular Cascaded Solid-State Transformer

固态变压器作为未来智能电网中的核心设备,是一种基于电力电子变换技术实现传统变压器功能的新型智能变压器。模块级联固态变压器可以使低压器件工作在高压情况下,以提高电压等级,使其应用于电网中。模块式级联固态变压器整流级直流侧电压不均是该拓扑一个重要问题。因此从级联式拓扑直流侧电压不均的实质出发,提出一种调节调制波矢量有功分量的大小,重新构造各模块的调制波,使有功功率的重新分配以实现均压的策略,并给出了控制流程。最后通过仿真和搭建实验平台来验证,经仿真和实验效果来看,该均压策略是可行的。

As a core device of the smart power grid,the solid-state transformer is a new-type intelligent transformer based on power electronics technology.It can realize the function of traditional power transformer.Modular cascaded solid-state transformer allows low-voltage devices to operate under high-voltage condition to enhance the level of voltage.The modular cascaded type is applied to power grid.According to the substance of voltage unbalance,we investigated a strategy which changes the active component of the modulation wave vector to achieve the active power redistribution of the system.The process of the strategy is also described here.Finally,the strategy is tested by simulation.According to the result of the simulation,the voltage balance control strategy is effective.