Microprocessor-Based Universal Regulator Using Dual-Rate Sampling

Standard single-rate sampling self-tuning regulators may not be able to effectively control fast-acting systems if the minimum computation time required is larger than the largest sampling period permissible. A dual-rate sampling self-tuning regulator that overcomes this problem by allowing a data sampling rate to be chosen consistent with the system time constants and a control output interval based on the computation time is described in this paper. This algorithm is also very suitable for implementation using fixed word-length processors as the quantization problems are minimized. The algorithm has been implemented on a microprocessor. Implementation details with emphasis on data acquisition, interrupt controlled sampling, time sufficiency test and scaling, and experimental results are also given.