Debugging of the PDF controller
After a week of debugging and modification, the output (zone temperature) is finally around the target value (21 degree or 294 F). However, there always exists oscillation. Meanwhile, the temperature can`t achieve the target value when the SAP time period is short like 2 hours.
It is not easy to find the problem, because there many equations and connect with each other to form many loops. The reason may due to the calculation of COP or Max heat pump output, may due to the calculation of PDF control, may also due to the value setting of parameters within radiator system. Meanwhile, it`s hard to separate anyone cause while keeps others the same.
After a meeting with my supervisor, he advises me to consider the model separately. Replacing the "ASHP & Radiator" block with an ideally transfer function, then try to find out the best suitable value of controlled value for Kp and Ki. After that, put the original "ASHP & Radiator" block back and find whether the problem is from controller or heat pump itself. I will use this method for the next week.
