Application of pulse width modulation and by-pass valve control for increasing energy efficiency of pneumatic actuator system

Control of a pneumatic actuator using pulse width modulation (control) represents a good alternative for control of pneumatic actuator that uses proportional valve. Important advantage of pulse width modulation control is fewer consumption of compressed air. In addition, air consumption can be further reduced by the use of inter-chamber cross flow (chamber by-passing). This article discusses joint application of pulse width modulation and by-pass chamber control on the example of pneumatic rodless cylinder which is controlled by programmable logic controller. Saving of compressed air was experimentally determined, as well as the influence of inter-chamber cross flow on the quality of the control. With this application of pulse width modulation and by-pass valve control, pneumatic actuator system shows that 30% of energy can be saved under the same working conditions in comparison to the traditional pulse width modulation control system.