Primary Frequency Control Ability Evaluation of Valve Opening in Thermal Power Units Based on Artificial Neural Network

Abstract

With the development of new energy, the primary frequency control (PFC) is becoming more and more important and complicated. To improve the reliability of the PFC, an evaluation method of primary frequency control ability (PFCA) was proposed. First, based on the coupling model of the coordinated control system (CCS) and digital electro-hydraulic control system (DEH), principle and control mode of the PFC were introduced in detail. The simulation results showed that the PFC of the CCS and DEH was the most effective control mode. Then, the analysis of the CCS model and variable condition revealed the internal relationship among main steam pressure, valve opening and power. In term of this, the radial basis function (RBF) neural network was established to estimate the PFCA. Because the simulation curves fit well with the actual curves, the accuracy of the coupling model was verified. On this basis, simulation data was produced by coupling model to verify the proposed evaluation method. The low predication error of main steam pressure, power and the PFCA indicated that the method was effective. In addition, the actual data obtained from historical operation data were used to estimate the PFCA accurately, which was the strongest evidence for this method.