电压源换流器闭环控制的实时联合仿真

Real-time Co-simulation for Voltage Source Converter Closed-loop Control

为解决电压源换流器闭环控制实时仿真中计算效率和仿真精度难以兼顾、计算量大的问题,提出了基于现场可编程逻辑门阵列(FPGA)、数字信号处理器(DSP)、个人计算机(PC)架构的电力电子实时联合仿真方案。该方案为电力电子系统提供了一个多速率仿真平台。在该平台上,采用连续–离散模型分离法分割电压源换流器模型以及提取参数,采用开关函数法与状态空间法设计浮点型解算器,运用系统快速成型法快速建立仿真系统模型。对三相两电平逆变器闭环控制系统算例进行实时多速率仿真测试,FPGA以500 ns的仿真步长实现逆变器的高速解算,DSP以2μs的步长实现控制部分的低速仿真。结果表明:实时联合仿真比多速率离线仿真提速233倍,比单速率离线仿真提速991倍,且范式误差仅为1%,显著提高了仿真准确度与计算效率;且系统快速成型法采用自动代码生成技术,明显缩短了开发周期。

In order to solve the problems of the conflict between computational efficiency and simulation precision, as well as a large amount of calculation in real-time simulation of voltage source converter closed-loop control, we put forward a co-simulation design scheme for the power electronic real-time based on FPGA＋DSP＋PC architecture. The design scheme provides a multi-rate simulation platform for power electronic system. In the platform, we adopt a continuous-discontinuous model separation method to segment VSC model and extract the parameters, combine switching-function approach with state-space approach to design the float point solver, and use a system rapid prototyping method to build a simulation system model. A three-phase two-level closed-loop control system case is selected for real-time multi-rate simulation test. The FPGA calculates inverter with 500 ns simulation step and the DSP simulates closed-loop control part with 2 μs. The results show that the real-time co-simulation is 233 times faster than the multi-rate off-line simulation, 991 times faster than the single rate off-line simulation, and the Euclidean norm is 1%, significantly improving the simulation precision and calculation efficiency. And the system rapid prototyping method using automatic code generation technology can obviously shorten the development cycle.