We are using PLECS standalone 4.5.5 (64 Bit). we have a problem with the AC sweep analysis results related to the boost converter model.
We want to perform AC analysis to measure the plant once with perturbation/response block in open loop (control to output) as Figure ''Plant in OL" and once with loop gain meter block in feedback as Figure "Plant in CL".
If the loop gain meter can measure the open loop transfer function in the closed loop, the results of both tests must be the same, but they are not like the figure "Results".
We want to know what the reason is, because we will use the PLECS to simulate the test bench.
On the test bench, we also use the AC sweep method, but the plant must be measured in closed loop, so it is very important for us to trust the simulation result. If we want to simulate what we do on the test bench, we should use the loop gain meter block in our simulations.