Frequency Domain Analysis and Engineering Application of Lambda Tuning Method
Lambda is an effective PID controller engineering tuning method for self-regulating processes.The closed-loop control system using this tuning method is analyzed in frequency domain,and the calculation formulas of Phase margin and amplitude margin are given.And λ was analyzed.When λ=τ The Phase margin and amplitude margin reach 61.4° and π re-spectively,and these two parameters are very close to the optimal margin recommended.When the controlled process is a high-order process,an engineering method based on response curve control model identification can be used to obtain the effective model gain,effective time constant,and effective deadtime of the control model.Then,the Lambda tuning formula is used for PID tuning.The simulation results demonstrate the effectiveness of the obtained model process and tuning method.