模块化多电平换流器(MMC)在柔性直流输电领域得到了广泛的应用。在高压大功率场合,MMC的子模块数量庞大,子模块故障是一种常见的故障类型。为了提高可靠性,通常MMC每个桥臂上均设置一定数量的冗余子模块。然而,当MMC发生不对称子模块故...模块化多电平换流器(MMC)在柔性直流输电领域得到了广泛的应用。在高压大功率场合,MMC的子模块数量庞大,子模块故障是一种常见的故障类型。为了提高可靠性,通常MMC每个桥臂上均设置一定数量的冗余子模块。然而,当MMC发生不对称子模块故障时,直流电流中会出现基频波动,影响MMC的运行性能。针对上、下桥臂同时存在故障子模块的工况,分析了MMC桥臂间能量平衡的条件。据此,提出了一种能量再平衡控制策略,以抑制直流电流中的基频波动。与传统控制策略相比,在额定冗余运行域内,所提控制策略无需提高子模块电容电压。分析了采用所提控制策略时MMC的最大安全运行域,结果表明所提控制策略能扩展MMC的安全运行域,进一步提高其可靠性。±350 k V/1 000 MW的MMC硬件在环实验结果验证了所提能量再平衡控制策略的有效性以及安全运行域分析的正确性。展开更多
A realization of three phase to three phase matrix electric power converter (33MC) with practicality is depicted, which is characteristic of modular configuration, simple and safe semi natural semi forced two step ...A realization of three phase to three phase matrix electric power converter (33MC) with practicality is depicted, which is characteristic of modular configuration, simple and safe semi natural semi forced two step commutation strategy, general over current protection circuit, flexible generalized switching functions, combined bilateral power switches, and so on. A new approach to manufacturing oriented 33MC comes forth, which is composed of 3 modular three phase to single phase non square matrix electric power converters (31MC).展开更多
文摘模块化多电平换流器(MMC)在柔性直流输电领域得到了广泛的应用。在高压大功率场合,MMC的子模块数量庞大,子模块故障是一种常见的故障类型。为了提高可靠性,通常MMC每个桥臂上均设置一定数量的冗余子模块。然而,当MMC发生不对称子模块故障时,直流电流中会出现基频波动,影响MMC的运行性能。针对上、下桥臂同时存在故障子模块的工况,分析了MMC桥臂间能量平衡的条件。据此,提出了一种能量再平衡控制策略,以抑制直流电流中的基频波动。与传统控制策略相比,在额定冗余运行域内,所提控制策略无需提高子模块电容电压。分析了采用所提控制策略时MMC的最大安全运行域,结果表明所提控制策略能扩展MMC的安全运行域,进一步提高其可靠性。±350 k V/1 000 MW的MMC硬件在环实验结果验证了所提能量再平衡控制策略的有效性以及安全运行域分析的正确性。
文摘A realization of three phase to three phase matrix electric power converter (33MC) with practicality is depicted, which is characteristic of modular configuration, simple and safe semi natural semi forced two step commutation strategy, general over current protection circuit, flexible generalized switching functions, combined bilateral power switches, and so on. A new approach to manufacturing oriented 33MC comes forth, which is composed of 3 modular three phase to single phase non square matrix electric power converters (31MC).