In industrial production processes

time delays can have adverse effects on the performance of control systems

and may even lead to system instability. This article investigates the stability issues of time-delay in the load/speed control loop of a heavy-duty gas turbine from the perspective of switching systems. The model of GE MS109FA 275 MW heavy-duty gas turbine under 100% load is taken as the research object. The load/speed control loop with time-varying delay is transformed into a class of switching system by augmenting the state variable and selecting the change of time delay as the switching signal. By using the norm correlation lemma

a necessary and sufficient condition to ensure the stability of the load/speed control loop with time-varying delay is derived and the stability verification algorithm is given. The hardware-in-the-loop simulation is carried out based on the domestic heavy-duty gas turbine NuCON control system. The results of this study can provide theoretical references for the design and parameter adjustment of heavy-duty gas turbine control system.