Detail Artikel

Energy and Compressor Performance of an Air Conditioning System using PID Controller

CONCLUSION

The controllers i.e. on/off and PID were developed to control the motor speed in order to maintain the room temperature at or close to the setpoint temperature. The on/off controller is used in many simple control systems, the controller turns on the motor compressor when the room temperature reaches the upper limit temperature setting, and turns off at the lower limit temperature setting. The PID controller tries to minimize the error between the setpoint temperature and the room temperature. If the room temperature reaches the setpoint, the motor speed abruptly reduced and fluctuates to maintain the room temperature. However, when the room is thermal loaded, the controllers act such that the heat recovery to the room is fast until the temperature setpoint is upheld again. The energy consumption would change with the change in motor speed. When the motor speed increases, the room temperature decreases and COP increases with the increase in energy consumption. Furthermore, the higher the energy consumption the smaller is energy saving.

A well-tuned PID controller that produced satisfactory solution in term of energy saving for the room was employed. The impacts of all controllers on the performance of the system, the room temperature and energy consumption have been analyzed experimentally. The trend of compressor performances in term of COP is found to be similar for all controllers studied. Energy analysis shows that PID controller gives the highest saving followed by PD, PI, and P in comparison with on/off controller. The main outcome of this study shows that using VSC and choosing suitable control strategy, it is capable to control the space temperatures with significant energy saving.

REFERENCES

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Dr. Ir. Henry Nasution, M.T
Staff Jurusan Teknik Mesin
Fakultas Teknologi Industri
Universitas Bung Hatta