In DCMotorControlPumpElectricDC the armatureInverter component is used to control the power of the electric motor driving the pump. As far as I understand, the armatureInverter converts the voltage from the battery to the specified Vref at the motor. In case of DCMotorControlPumpElectricDC, armatureInverter is controlled with a current reference, leading to weird behavior in the control loop. Connecting armatureInverter.vMot to currentController.u_m would solve the issue.