Optimized method for controlling position and crossover pressure in a double acting actuator

A system comprising:

• a double-acting pneumatic actuator having a first pneumatic chamber and a second pneumatic chamber;
• a first sensor to determine pressure in the first chamber;
• a second sensor to determine pressure in the second chamber;
• and
• a controller configured to:
• monitor a crossover pressure over the two pneumatic chambers using the first and second pressure measurements,
• determine that the monitored crossover pressure is outside of a predefined deadband range corresponding to values extending above and below a crossover pressure set point,
• in response to determining that the monitored crossover pressure is outside of the deadband range, determine a difference between the monitored crossover pressure and the crossover pressure set point to generate a crossover pressure error,
• execute a control action to drive the monitored crossover pressure to the crossover pressure set point, using the crossover pressure error,
• in response to determining that the monitored crossover pressure has reached the set point, set the crossover pressure error to zero, and
• maintain the crossover pressure error at zero while the monitored crossover pressure is within the deadband range.

A controller configured to digitally control a double-acting pneumatic actuator, the controller including:

• processing hardware;
• and
• a memory storing thereon instructions that, when executed by the processing hardware, cause the controller to execute a method including:
• monitoring a crossover pressure over two pneumatic chambers of the double-acting pneumatic actuator,
• determining that the monitored crossover pressure is outside of a predefined deadband range corresponding to values extending above and below a crossover pressure set point,
• in response to determining that the monitored crossover pressure is outside of the deadband range, determining a difference between the monitored crossover pressure and the crossover pressure set point to generate a crossover pressure error,
• executing a control action to drive the monitored crossover pressure to the crossover pressure set point, using the crossover pressure error,
• in response to determining that the monitored crossover pressure has reached the set point, setting the crossover pressure error to zero, and
• maintaining the crossover pressure error at zero while the monitored crossover pressure is within the deadband range.