|Simple Electric Heater Model and PI Control Simulation
We are completing work on the HVAC Plant Models for creating simulations of both
the controlled plant and the control system. We have completed the control side
with a set of attribute files for our Graphic Program Generator that are compatible
with the symbol set used with our WinPRO/HVACPRO Application Builder.
This allows simulation and testing of control processes without the hardware. In this
application of the Graphic Interface System the SWFSCRIPT scripting language is used
to run the models. The HTML pages including graphics and scripts are created using our
Graphic Program Generator, a general purpose tool. In the example shown above the Plant
side HTM page was loaded. It then opened another browser window and loaded the control
side HTM page. Both pages began executing their scripts. They operate with their own local
variables and send data between each other using global variables. In the example the
electric heating coil is controlled by the PI controller to maintain the DAT, Discharge Air
Temperature at 62.0 degF. After achieving setpoint the setpoint is changed to 85.0 degF. The
Trend Graph shows the response. The green line is the electric heater command, the red line
is the Discharge Air Temperature as read by the temperature sensor.
Current price of the SWFTEC Graphic Interface System is $100.00 USD including a graph
plotting utility. The price of the SWFTEC Graphic Program Generator is $100.00 USD.
Click here to E-Mail for more info
Click here to return to Main Pageor Click BACK on your Browser.