One-cycle-controlled PWM for on-off valve and pneumatic actuation system

Using pneumatic and fluid power for actuation purposes has many advantages, including the system's high ratio of force over mass, its cleanliness, high serviceability and low cost. The key element of a fluid and pneumatic system is the valve. Thanks to new advances in valve technology, a faster and more accurate binary on-off valve can replace the more expensive servo valve for servo control purposes.; In this research, we developed control schemes to control binary on-off valve and pneumatic actuation system. For on-off valve control, we have adapted an integration-reset pulse width modulation method called One-Cycle Control (OCC PWM) to convert a solenoid on-off valve, which is discrete, to a continuous and linear servo valve. One-Cycle Control has been developed and used in Power Electronics applications, where the switching time delay is negligible, to perform current or voltage conversions. In order to use this method for a mechanical valve, a mechanical delay control scheme was developed. The frequency content of the One Cycle Controlled signal was also analyzed as this frequency information was important for use in the new on-off valve design. For the pneumatic actuation system control, we proposed new dynamic models and control laws. The new dynamic models are meant to simplify the system modeling and to facilitate use of available nonlinear control laws found in the literature; such as feedback linearization and sliding mode control. Some of our control laws treat on-off valve as an integrated part of the pneumatic system, whereas some require the use of servo valve only. In the latter case, OCC PWM is used to convert on-off valve to servo one before being used in the system.; The organization of this work is divided into two parts, the valve part and the pneumatic actuation part. The first part presents the dynamics of the on-off valve along with the control schemes that make it work as a continuous and linear device. The latter part discusses the position tracking control of the actuation system using nonlinear dynamics models.