Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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EEV Superheat Control of a Multi-type Heat Pump by Using Dither Signal

멀티형 히트펌프 전자팽창밸브의 디더 신호를 적용한 과열도 제어

  • 한도영 (국민대학교 기계ㆍ자동차공학부) ;
  • 표수환 (국민대학교 기계공학과 대학원)
  • Published : 2002.11.01
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Abstract

The electronic expansion valve (EEV) may be used to control the refrigerant flow rate for the multi-type heat pump. Stepping motor driven EEV may precisely control the refrigerant flow rate to meet each internal load requirement. To control the EEV, PI algorithm may be used. But the hysteresis of EEV deteriorates the performance of superheat control. To reduce the performance degradation, the PI algorithm along with the dither signal may be used. The dither signal, with about 10 times higher frequency than the system crossover frequency and about 10 times larger magnitude than the deadband of hysteresis, was selected for the superheat control of EEV. Experimental results showed the improvement of EEV control by adding the dither signal to the PI algorithm.

Keywords

References

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