Control loop stability measurement in PSU

What is control loops in SMPS?

Switched Mode Power Supplies (SMPS) use control loops to ensure that the working point is obtained with the minimum steady state error and fast transient response. To achieve these objectives, a strong control action is needed. But if this action is too aggressive, it can make the system unstable, lead to oscillations that can increase ripples, component stress or even damage the converter or loads.

The control action can be estimated with linear control calculation techniques. It is because, although SMPS are nonlinear, time varying systems due to the switching actions, they can be modeled with an averaged small-signal linearized model.

In this technical article our RDI team give you some good practices and tips for control loop ajust and its mesuaring in our power converstion systems.