At a hydroelectric plant, the customer needed to add additional monitoring information on their HMIs at three locations. The PLC's the customer is using are out of production and the HMI software is cumbersome and slow. CTD was able to add the new points to the PLC and update the HMI screens to the customers specifications. This allows the customer to postpone the expense of upgrading their control system until a later time when funding becomes available. CTD has also proposed a state of the art PAC upgrade for this facility that is a fraction of the cost of a DCS upgrade and will interface directly with their remote DCS already in place.

A customer needed to improve their spinning reserve capacity. The 150 MW gas wall fired boiler was only capable of 2 MW/min. Several areas of the complete system needed to be addressed. The gas fuel pressure and flow control valves needed to be decoupled to prevent interaction. The drum level controls were changed to 4-element controls to improve stability, the turbine/boiler coordinated control system was modified to allow for smoother operation of the entire unit, and the entire system was retuned. The result was that the unit is now able to reliably ramp at 6MW/min which greatly improved the spinning reserve capacity of the unit. The customer immediately realized savings of $24,000 to $46,000 per month depending on conditions!

At a 1X1X1 combined cycle plant, the owner would receive a premium if they were able to initiate duct burner firing and reach maximum load within 10 minutes, including the 3 minute purge time of the duct burners. Using advanced system modeling and several logic improvements the goal was met. As a result the customer receives a contracted $1,000/MW-hr for this ability with the duct burners. In addition CTD was able to automate the firing and allow the entire unit to operate on AGC reliably.

Advanced Process Controllers are being added on many boilers to improve emissions. CTD was able to install the interface and build the graphics for operator use on a 450MW coal unit. The entire work took less than 5 days on site with no interruption to the operation of the plant.

©2009 Controller Tuning & Design, LLC