The real-time simulation of the modular multilevel converter-based high-voltage direct current (MMC-HVDC) transmission system has become a popular research topic. However, in order to meet the real-time performance, the real-time simulation technology will cause additional simulation errors for MMC-HVDC, especially on its frequency characteristics. Therefore, a parallel multi-rate simulation scheme for MMC-HVDC is developed in this work to ensure accurate simulation of high-frequency characteristics. Firstly, a non-error method based on converter transformer decoupling is proposed to decouple the converter and alternating current system; direct current transmission line decoupling and arm decoupling methods are used to achieve decoupling among and within converters. A multi-rate data synchronous mechanism is established by considering the differences among high-frequency characteristics caused by delayed data interaction. Secondly, the computing architectures of the primary system solver and modular multilevel converter controller are designed based on a field programmable gate array (FPGA). The real-time simulation platform for a four-terminal true bipolar MMC-HVDC is constructed based on the FPGA array. Thirdly, the factors in multi-rate simulation affecting the simulation accuracy of high-frequency characteristics are analysed. The simulator is shown to be accurate in steady and dynamic states. The authors also verify its applicability for further research on high-frequency resonance based on control experiments.

中文翻译：

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基于模块化多电平转换器的高压直流并行多速率仿真方案，具有高频特性的精确仿真和基于现场可编程门阵列的实现

基于模块化多电平换流器的高压直流（MMC-HVDC）输电系统的实时仿真已成为热门研究课题。然而，为了满足实时性，实时仿真技术会给MMC-HVDC带来额外的仿真误差，特别是其频率特性。因此，本文开发了MMC-HVDC的并行多速率仿真方案，以确保高频特性的精确仿真。首先，提出一种基于换流变压器解耦的无误差方法，实现换流器与交流系统的解耦；采用直流传输线去耦和臂去耦方法实现转换器之间和内部的去耦。考虑数据交互延迟造成的高频特性差异，建立多速率数据同步机制。其次，基于现场可编程门阵列（FPGA）设计了主系统求解器和模块化多电平转换器控制器的计算架构。基于FPGA阵列构建了四端真双极性MMC-HVDC实时仿真平台。再次，分析了多速率仿真中影响高频特性仿真精度的因素。该模拟器在稳态和动态状态下都是准确的。作者还基于控制实验验证了其对于进一步研究高频谐振的适用性。