Virtual Reference Feedback Tuning (VRFT) is a data-based controller tuning method wherein tuning is carried out directly from process input-output data without resorting to process identification. Although VRFT eliminates the need for a process model, the design methodology involves the use of a reference model and the selection of an appropriate reference model still remains an open problem. In this work, a generalized second-order reference model containing time delay and zero dynamics is derived. Furthermore, VRFT design equations using this reference model for two classes of linear controllers i.e. PID controller and a high-order controller with integrator, are developed. Simulation results are presented to illustrate the applications of the proposed design method and a comparison with existing data-based design methods and model-based design methods is made.

虚拟参考反馈调整（VRFT）是一种基于数据的控制器调整方法，其中调整直接从过程输入输出数据执行，而无需借助过程识别。尽管VRFT消除了对过程模型的需求，但是设计方法涉及参考模型的使用，而选择合适的参考模型仍然是一个未解决的问题。在这项工作中，导出了包含时间延迟和零动力学的广义二阶参考模型。此外，开发了使用该参考模型的VRFT设计方程，用于两类线性控制器，即PID控制器和带积分器的高阶控制器。