The position error represents the stationary deviation between the setpoint and actual value for a position in the closed circuit position control system. Since the hydraulic controlled subsystem does not demonstrate any integrative behaviour of a subsystem, there will not be any stationary or residual control deviation in theory if there is no external load acting on the system. Any position errors occurring in hydraulic closed circuit position control systems are either caused by external loads — in connection with a finite force gain for the control element — applied to dead zones as a result of positive overlap/underlap conditions of valves, or they are caused by reversal errors associated with control circuit elements.
The position error can be reduced by increasing the loop gain or having an integrated element in the controller, although the stability criteria must be satisfied.