Discrete to continuous model conversion for multiple state-delay system with a singular continuous-time system matrix based on matrix sign function

The analysis of discrete to continuous model conversion for multiple state-delay system with a singular continuous-time system matrix based on the computationally fast and numerically stable matrix sign function is firstly presented in this paper. The proposed methodology yields a more accurate model conversion than existing methods which just approximately solve the equivalent mode. Finally, the accuracy of theoretical results is illustrated through an example.