Simulation Research on the Frequency Characteristic of Zero Order Holder

The frequency characteristic of zero order holder is one of the important concepts in studying the performance of sampling control system,but different phase frequency characteristic curves of zero order holder are presented with only conclusion in the published textbooks of automatic control principle,computer control technique and computer control system.In view of this situation,the frequency characteristic of zero order holder is simulated and researched in detail with three ways including of Pade approximation method,direct computation method and step-by-step computation method,and the results of the tree methods are same.