中文摘要：

矩阵变换器由于其自身结构的特殊性，易受输入侧电源异常的影响。针对电网对地短路的情况，建立电网故障下的系统等效数学模型。提出一种新的开关控制策略，通过分时赋值9组双向开关的控制信号来确保矩阵变换器安全度过电网故障期。利用Matlab/Simulink来模拟矩阵变换器直接转矩控制系统在电网正常和电网故障情况下的工作状态，编写基于C语言的DSP程序和VHDL语言的FPGA程序来实现提出的控制策略。最后，设计出一套高度集成的矩阵变换器实验装置，通过实验平台验证提出的开关控制策略。仿真和实验结果表明了所提控制策略的正确性，验证了设计的矩阵变换器直接转矩控制硬件和软件系统具有电网故障跨越的能力。

英文摘要：

Due to the particularity of its own structure,matrix converter is vulnerable to the abnormal power supply of input side.In this paper,the equivalent mathematical model of the system is established under grid failures according to short circuit grounding faults.A new switch control strategy is proposed.This strategy ensures the security of matrix converter through the control signals of9groups of bidirectional switches being given respectively in different time under grid faults.The working conditions of matrix converter under normal and abnormal states of grid are simulated in Matlab/Simulink.Then DSP and FPGA algorithms are designed respectively in C language and VHDL to perform the proposed control strategy.Finally,a highly integrated experimental platform of matrix converter has been developed to verify the proposed switching control strategy.It is shown that the control strategy can not only make the speed control system have good static and dynamic performances,but also simulate the various conditions of matrix converter correctly under normal or abnormal grid operations.That is to say the matrix converter-induction motor direct torque control system has the capability of crossing grid faults.