Patent ID: 8195312
Filing Date: 2012-06-05
Classification: G05B,G05D

Abstract:
1. A mass flow controller comprising, a digital controller adapted to implement a control loop having a proportional signal modifier, including a differentiation module, in series with an integral signal modifier, the proportional signal modifier receives a measured flow rate signal and generates a proportional modifier output signal, the integral signal modifier being adapted to (i) receive a combination signal comprising an error signal and the proportional modifier output signal, and (ii) output an integrated signal; a valve adapted to receive the integrated signal and adjust a valve opening in accordance with the integrated signal; and a sensor adapted to output the measured flow rate signal indicative of an actual fluid flow rate in the mass flow controller, the measured flow rate signal being (i) received by the proportional signal modifier, and (ii) used in conjunction with a setpoint signal to determine the error signal.