Integral windup
Integral windup, also known as integrator windup or reset windup, refers to the situation in a PID controller where a large change in setpoint occurs (say a positive change) and the integral term accumulates a significant error during the rise (windup), thus overshooting and continuing to increase as this accumulated error is unwound (offset by errors in the other direction). == Solutions == This problem can be addressed by Initializing the controller integral to a desired value, for instance to the value before the problem Increasing the setpoint in a suitable ramp Conditional integration: disabling the integral function until the to-be-controlled process variable (PV) has entered the controllable region Preventing the integral term from accumulating above or below pre-determined bounds Back-calculating the integral term to constrain the process output within feasible bounds.