The Heating, Ventillation, and Air Conditioning Trainer Qnet

...

(7) When we changed Vh_amp to 3.00V, the heater voltage was constantly 3.8V and but the chamber temperature had increased to 24.5C.

(8)

(9) When we changed Dth=0.5C , the both temperatures and the heater voltage were starting to become more steady.

-

Modeling

(6) After we adjusted the Signal Generator and the Control Parameters, the heater voltage increased to 3.9V and chamber temperature decreased to 24.3C.

[pic 19]

Experiment 6.2

-

PI Control with Anti-Windup

(8) After we input the values, the chamber temperature changed to 24.6 C and the ambient temperature became 22.6C.

(9) when we set ki to 0V/(C.s) and changed kp to 5 V/C, the chamber temperature decreased to 23.3C but the ambient temperature on the figure had become more steady which we can observe that temperature didn’t change.

(10) When we set kp= 0.5V/(C.s) and ki=0.75 V/(C.s), the temperature control performance haven’t changed such a big. The chamber temperature had become 23.5C and ambient temperature became 22.7C.

-

Effect of Saturation and Windup

(5) The signal in the Voltage (V) scope saturated to 8 V. (Maximum Voltage 8V)

(6)On the temperature scope we can see that between the maximum actual temperature and minimum temperature difference is vast. But there hasn’t any overshoot.

(8) Setting the small value in set- point can decrease the anti-windup reset parameter.

-

Effect of Set-Point Weight

(5) The chamber temperature is 23.7C

The ambient temperature 22.7C

Heater Voltage 3.8V

(7) When we raised bsp to 1, it influenced for the actual temperature to become more constant.

-

PI Control according to Specifications

(9) The measures temperature hadn’t shown big difference. Only the chamber temperature decreased to 23.5C. But the control system started to measure the overshoot.

(11) When we changed zeta to 0.9, it not only caused the raise of temperature to 24.4C, but also increased kp to 20.1 V

(13)When we changed w0= 0.09 rad/s, it decreased the kp to 14.5 V and p0 (percentage of overshoot) to 0.67%.

D0047519 柯莉娜

In our most recent lab experiment, we were working with the HVACT module of QNET system using NI ELVIS. We used the NI ELVIS program to control the temperature inside a tube that contained a halogen lamp by adjusting the voltage to both the lamp and the cooling fan attached outside.

Generally speaking the experiment itself was not overly complicated and involved a lot of waiting around. Except for a few small mistakes when inputting the control variables the experiment as a whole went quite smoothly. Seeing as this is the last experiment of this semester, looking back, I realized that we have come a long way in understanding all the linear control theory that we studied in class. All in all I think we all learned a great deal about the NI ELVIS toolset and thus gained important practical experience on Linear Control theory.

D0047212 許子林

Our recent lab experiment was titled QNET-HVACT. Initially I thought that it was going to be quite a complicated experiment but it turned out differently than what I expected. We as a group spent much of our time waiting on the NI ELVIS scope results actually. Our experiment involved changing the temperature of a halogen lamp chamber through voltage control. This turned out to be quite easy and we completed the experiment without a lot of difficulty. In the last experiment we had some experience with controlling the overshoot and undershoot and settling time etc of the experiment and this experiment was not so different. Our goal was to minimize the settling time and shorten the overshoot. Doing two similar experiments in a row only served to cement our understanding of that Linear Control theory principle. Even though this is the last experiment of this semester, I feel that I have learnt a lot regarding the many aspects of Linear Control theory over the course of these lab experiments. My thanks goes to the Professor and the teaching assistants for their time and effort to give us a more practical understanding of this particular topic.

D0076238 宋振宇

This time’s Experiment was difficult and step is complex .We needed to print screen for get few photos. But during our experiment our results were different than what we’ve expected. So we decided to pick up the half of experiment which led us to success our results.But report’s questions were hard for us and we took very long time to answer. In conclusion, Automatic Control System Laboratory course helped us to understand difference between theoretical knowledge and practical knowledge.

Moreover, this course was interesting and challenging for all of our classmates. Especially, it proved to me that at least i must have ability to write my opinion in English.