Temperature Control of Hot Wind Tunnel by Using Cascade Integral Separated PI and Proportion Control Law

Temperature control is an important index to evaluate the performance of hot wind tunnel. Therefore, this paper designs a cascade integral separated proportion integral and proportion(PI-P) control law to control the temperature of the hot wind tunnel. The mathematical models of the fuel oil flow rate and combustor temperature are established. The reference flow rate of the flow rate loop is obtained by querying the temperature-flow (T-q) table, and then reference flow rate and the compensation flow rate obtained by the temperature control algorithm are superposed to reach the target temperature. P control is adopted to control the fuel oil flow rate in the inner loop by controlling the position of the digital valve. The integral separated PI control is used to control the temperature in the outer loop. The step response at 1200℃, 1400℃ and 1600℃ is simulated and tested. The results show that the cascade integral separated PI-P control method proposed in this paper has good rapidity and stability.