EP0501432A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of controlling an air conditioning apparatus and air conditioning apparatus using the method
Assignee: Hitachi Ltd
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Filing: 1992-02-25
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Granted: —
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Expires: 2012-02-25
Abstract
Abstract The present invention discloses a novel method of controlling an air conditioning apparatus and an air conditioning apparatus utilizing the control method. The method of controlling an air conditioning apparatus according to the present invention comprises the steps of sucking and cooling air in a room; measuring an air temperature in the room and a temperature of cooled air discharged to the room; determining a first difference value (ΔT1 corresponding to the difference between the measured air temperature in the room and a target value of the room temperature; determining a second difference value (α·ΔT2) corresponding to the difference between a target value of the discharged air temperature lower than the target value of the room temperature by a predetermined value and the measured value of the discharged air temperature; generating a control signal (ΔT) corresponding to the difference between the first difference value (ΔT1 and the second difference value (α·ΔT2); and controlling a rotational speed of a compressor of the air conditioning apparatus in accordance with the value of the control signal (ΔT) and the measured value of the air temperature in the room, so as to maintain the difference between the target value of the room temperature and the discharged air temperature to be a predetermined constant value.
Inventors
- 👤 Tetsunobu Okamura
- 👤 Kiyoshi Nagasawa
- 👤 Kuniyuki Hitachi Minamikashiwa Yamada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 10:10
CPC Classifications
F; F24; F24F; F24F11/00; F24F11/30; F24F11/46; F24F11/62; F24F11/63; F24F11/70; F24F11/80; F24F11/86; F24F2110/00; F24F2110/10; F24F2221/00; F24F2221/34
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
187 words
A method of controlling a cooling operation in an air conditioning apparatus, comprising the steps of: sucking and cooling air in a room; measuring an air temperature in said room and a temperature of cooled air discharged to said room; determining a first difference value (ΔT1) corresponding to the difference between the measured air temperature in said room and a target value of the room temperature; determining a second difference value (α·ΔT2) corresponding to the difference between a target value of the discharged air temperature lower than said target value of the room temperature by a predetermined value and the measured value of the discharged air temperature; generating a control signal (ΔT) corresponding to the difference between said first difference value (ΔT1) and said second difference value (α·ΔT2); and controlling a rotational speed of a compressor of said air conditioning apparatus in accordance with the value of said control signal (ΔT) and the measured value of the air temperature in said room, so as to maintain the difference between said target value of the room temperature and said discharged air temperature to be a predetermined constant value.
Claim 2
Dependent Claim
84 words
A control method according to claim 1 further including: a first heating step for heating the cooled air, before it is discharged, after a predetermined time has elapsed from the start-up of the cooling operation; and a second heating step for heating the cooled air with a heating temperature of said heater lower than that obtained at said first heating step, when a measured value of said air temperature in said room has reached said target value of the air temperature in said room.
Claim 3
Dependent Claim
29 words
A control method according to claim 1, wherein said discharged air temperature is measured at an air discharge port of an indoor heat exchanger of said air conditioning apparatus.
Claim 4
Dependent Claim
198 words
A control method according to claim 1, wherein a rotational speed of said compressor is controlled in a PI control manner, with said value (ΔT) corresponding to the difference between the first difference value and the second difference value used as a proportional control term and a changing amount of the measured air temperature in said room used as an integral control term, where said control signal for the PI control is determined by the sum of a rotational speed derived by said proportional control term and a rotational speed derived by said integral control term, said proportional control term being derived from a table which contains previously determined values of rotational speeds with respect to values corresponding to said difference (ΔT) between the first difference value and the second difference value, and said integral control term provided for adding a predetermined value to a rotational speed derived from said proportional control value when a changing amount of a measured room temperature exceeds a predetermined temperature value and for subtracting a predetermined value from the rotational speed derived from said proportional control value when a changing amount of a measured room temperature is below a predetermined temperature value.
Claim 5
Dependent Claim
270 words
An air conditioning apparatus which utilizes a vapor compression cycle to cool a coolant and perform a heat exchange between air and the coolant through a heat exchanger (8) to cool down air, comprising: a first temperature sensor (1) for measuring an air temperature in a room; a second temperature sensor (3) for measuring air cooled by said air conditioning apparatus and discharged to said room; means (2) for setting a target value for a room temperature and a target value for a temperature of air discharged to said room at a value lower than said target value for the room temperature by a predetermined value; means (4) for determining a first difference value (ΔT1) corresponding to the difference between the air temperature in said room measured by said first sensor and said target value for the room temperature indicated by said setting means; means (4) for determining a second difference value (α·ΔT2) corresponding to a difference between said target value for the discharged air temperature indicated by said indicating means and the discharged air temperature measured by said second temperature sensor; means (4) for generating a control signal (ΔT) corresponding to the difference between said first difference value and said second difference value; and control means (4) for controlling a rotational speed of an compressor (5) of said air conditioning apparatus in accordance with the value of said control signal (ΔT) and the air temperature value in said room measured by said first temperature sensor to maintain the difference between said target value for the room temperature and the measured discharged air temperature to be a predetermined constant value.
Claim 6
Dependent Claim
97 words
An air conditioning apparatus according to claim 5, further including a heater (6) arranged near an air discharge port of said heat exchanger for heating air having passed through said heat exchanger, and wherein said control means further includes: means for conducting said heater to allow the same to heat after a predetermined time has elapsed from the start-up of a cooling operation; and means for adjusting a heating temperature of said heater when the air temperature in said room measured by said first sensor has reached said target value for the air temperature in said room.
References Cited (Backward Citations)
No citation records indexed.
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