模块化多电平换流器子模块故障模拟方法

Fault simulation method for sub-module in modular multilevel converter

控制保护装置作为柔性直流系统运行和故障时实现快速保护的关键设备,需要在投运前进行完整测试。现有测试手段是基于实时仿真平台的控制器在环测试,但由于模块化多电平换流器(MMC)子模块采用的是等效建模方式,这种测试方法不能详细模拟子模块的物理结构,因此无法有效模拟子模块故障,影响阀控功能的全面验证。为了解决上述问题,本文提出一种子模块故障模拟技术,该技术是在现有测试方法基础上加入故障模拟装置,能够实现子模块故障模拟,弥补现有测试方法的不足。最后实验室联调试验结果证明了所提方法的正确性和有效性。

The control and protection device,as the key equipment to realize rapid protection in the operation and fault of flexible DC system,,needs to be fully tested before being put into operation.The existing method is based on a real-time simulation platform for controller-in-the-loop testing.However,this test method cannot simulate the physical structure of the sub-module in detail because the modular multilevel converter(MMC)sub-module adopts an equivalent modeling method,so it cannot effectively detect the failure of the sub-module.Simulation affects the comprehensive verification of the valve control function.In order to solve the above problems,this paper proposes a sub-module fault simulation technology,which is to add a fault simulation device to the existing test method,which can realize the sub-module fault simulation and make up for the defects of the existing test method.Finally,the joint test results in the laboratory prove its correctness and validity.