High speed auto-tuning loop

A process control system for use in controlling a process, comprising:

• a controller device connected within the process to perform control activities within the process;
• a plurality of field devices communicatively coupled to the controller, each of the plurality of field devices including a processor and a memory;
• a control loop including a control entity and a measurement element, wherein the measurement element is stored in the memory and is adapted to be executed on the processor of a first one of the field devices;
• an auto-tuner adapted to tune the control loop, the auto tuner including;
• and
• a first tuning element configured to generate a tuning control signal to cause the control entity to drive the control loop to undergo a tuning procedure;
• a first data collection entity adapted to collect and store a plurality of control data signals associated with the control entity during the tuning procedure and a time indication associated with one or more of the control data signals;
• a second data collection entity disposed within the first one of the field devices and adapted to collect and store a plurality of measurement data signals associated with the measurement element during the tuning procedure and a time indication associated with one or more of the measurement data signals;
• and
• a second tuning element configured to receive the plurality of control data signals and the plurality of measurement data signals and to determine a tuning parameter for use in tuning the process control loop from the plurality of control data signals and the plurality of measurement data signals;
• wherein at least one of the first and second data collection entities is disposed within a different device than the first and second tuning elements.

A method for use in a distributed process control network to tune a process control loop having a control entity that controls at least one field device within the process and a measurement entity that measures a process variable within the process, the method comprising:

• forcing the control entity to control the at least one field device to implement a tuning procedure;
• collecting control data signals associated with the control entity during the tuning procedure within the at least one field device and storing the collected control data signals in a first data stack located in the at least one field device and storing a time indication associated with one or more of the control data signals in the first data stack;
• collecting measurement data signals associated with the measurement entity during the tuning procedure in a field device in which the measurement entity is located and storing the measurement data signals in a second data stack located in the field device in which the measurement entity is located and storing a time indication associated with one or more of the measurement data signals;
• sending the control data signals within the first data stack and the measurement data signals within the second data stack to a second tuning element;
• using the plurality of control data signals and the plurality of measurement data signals to determine a process characteristic for use in tuning the process control loop;
• using the process characteristic to generate one or more tuning parameters;
• and
• sending the tuning parameters to the control entity.