我做了个AC位置伺服系统解耦—变结构控的仿真,但运行时报错:Trouble solving algebraic loop containing block 'jieouzonghe/bianjiegou1/Gain1' at time 2.44153053238436e-010. Stopping simulation. There may be a singularity in the solution. If the model is correct, try reducing the step size (either by reducing the fixed step size or by tightening the error tolerances)