JPS5956650A - Air conditioner - Google Patents

Abstract

PURPOSE:To enable to drive the equipment with low power consumption by a method wherein the speed of a motor-driven compressor is controlled in response to the increase of detected air conditioning load in the range from the minimum speed to the maximum speed and, when the lowering of the air conditioning load is smaller than a predetermined value, the motor-driven compressor is controlled in response to said load. CONSTITUTION:During air conditioning drive, the rotational speed signal is obtained by means of a speed signal generator 4 in response to a temperature deviation obtained by means of a temperature deviation sensor 3 from both outputs of a room temperature sensor 1 and a target room temperature setter 2. Furthermore, the level of a temperature deviation signal is compared at an intermittent control signal generator 5, which outputs an operation instruction when the level of the temperature deviation signal is higher than a certain fixed level, while outputs a stop instruction when lower. Said speed signal is sent through a speed control signal comparator-selector 6 to the motor-driven compressor 7 in order to control the drive of the compressor 7 when the operation instruction is generated. Said generator 4 generates a speed signal, which increases with the increase of the temprature difference from the minimum speed to the maximum speed, and at the same time generates a speed signal in response to the load when the load lower below the predetermined value.

Description

[Detailed Description of the Invention] i@I13靜MO[RIUSE/j``9しY] The present invention relates to a compressor for compressing refrigerant, and an air conditioner that drives the compressor to air condition a room, particularly the compressor. This invention relates to a control method for a motor for driving a machine.

[Background of the invention]

In the conventional Air Conditioning Regulation No. 11, a constant-speed induction motor was often used as the motor for driving the compressor, and the operation and stop of the motor was controlled according to the difference between the indoor temperature and the target temperature. . In this type of control system, the motor frequently starts and stops, and a large current flows during startup, shortening the life of the motor, compressor, control equipment, etc., and the width of the room increases between starting and stopping. There were drawbacks such as large up and down movements and the heat exchanger was idle because the refrigerant did not flow to the heat exchanger while the motor was stopped. On the other hand, if the rotation speed of the electric motor is controlled according to the heating and cooling load and the heat exchanger's cooling is diverted to the secondary side, the heat exchanger will not play and the nitrogen i+?
, l The performance of the 11th unit jr is improved, low power consumption operation becomes rjJ function, and -r+iJ Nl, room temperature ->j:, it is possible to realize efficient air conditioning with less vertical vibration rjj.

Figure 1 shows such a rotation speed ft1ll (i111iJ
The relationship between the rotational speed of the electric compressor of a borrowed air conditioner and the cooling and heating capacity of an IF compressor (hereinafter referred to as a compressor) driven by a motor. to beat.

Above a certain number of revolutions N1, as the number of revolutions increases, the cooling and heating capacity increases, so the number of rotations of the dynamic compressor increases.
z, by controlling the number φ11, air i according to the cold J or heating load! ”, I sum (Ikuno;!i<roll n] ability. However, as you can see from this diagram, Den!
If the rotation speed of the compressor is extremely low, below a certain rotation speed N, the cooling capacity of the air conditioner will be low, and the air-conditioning capacity will be reduced by just operating the air conditioner. However, the disadvantage is that the electricity is insufficient.

′! ) D-5 Figure 2 shows the relationship between the T-mouth compressor rotation speed and the cooling efficiency or heating efficiency. Here, the cooling efficiency &, 1 heating efficiency η is defined as follows.

As can be seen from the figure, efficiency improves as the rotation speed decreases from the maximum rotation speed N4, but at a constant rotation speed N5 (Nl
On the contrary, as the dog gets smaller, its efficiency decreases. Therefore, even if the engine is operated at a rotation speed below N2 (Nl υ) which provides the same efficiency as the maximum rotation speed N4, the third
tJf shown in the figure, the rotation speed of the dynamic compressor is continuously increased to 11j'.
As is clear from the relationship between the rotational speed and power consumption when controlled, it is not a good idea in terms of power consumption.

[Purpose of the invention]

The present invention eliminates the drawbacks of the above-mentioned intermittent control and rotation speed control,
The purpose is to provide a ventilation system that requires less operating power, is comfortable, and has good air cooling (heating) performance.

[Summary of the invention]

The basis of the present invention is that the electric compressor is not operated at the rotational speed N2 or lower.

In other words, when the cooling/heating load is above a certain level, the rotation speed of the 'Iiii motor for driving the compressor is adjusted between the maximum rotation speed N4 and the minimum rotation speed N according to the cooling (heating) load. When the cooling (heating) load is below a certain level, the cooling (heating)
It was set so that it would operate intermittently between the minimum rotation speed N and stop depending on the heating load, and when the load exceeded a specified level, it would operate at maximum rotation and father N4. In this case, the operation is continued until the load falls below a predetermined value to improve the start-up of the cooling (heating) operation.Here, the minimum rotation speed N is between N2 and N4, and the air [1g] shall be determined taking into consideration other design conditions and performance conditions of the harmonizing device.

By implementing the present invention, the target controlled by the air conditioner, for example, the room temperature, is kept constant as shown in FIG. 4 by controlling the rotational speed of the compressor driving electric motor when the cooling load is above a certain level. It maintains the temperature at 6n degrees, has the same start-up performance as conventional air conditioners, and reduces the cooling (heating) load.
level, the intermittent control of the compressor drive motor causes a certain amount of vertical vibration in the chamber 7M18 to remain as shown in Figure 5, but it is not as large as with conventional intermittent control, and the number of intermittent vibrations is extremely high. This reduces the amount of air used, resulting in extremely comfortable air conditioning with a long equipment life. Furthermore, as described above, the operating performance of the air conditioner is greatly improved, resulting in significant savings in operating power.

[Embodiments of the invention]

Hereinafter, a method for controlling the rotation of a motor for driving a compressor in an air conditioner according to the present invention will be explained using examples.

FIG. 6 is a block diagram illustrating an embodiment of the present invention for controlling the room temperature in the desired air condition '2 [1], where 1 is an indoor temperature detector such as a thermistor, and 2 is an indoor target humidity setting. 3 is a temperature deviation detector, 4 is a speed signal generator, 5 is an intermittent control signal generator, 6 is a speed control signal comparison and selection device,
These components constitute a control command means 8 that generates an operation stop command and a rotational speed control command for the electric compressor 7, which will be described later. Moreover, air conditioning load detection means 9 is comprised by 1-3. The electric compressor 7 includes a compressor section, a frost motor section, and a speed control drive section that receives the above control command and controls the electric motor. Next, the control operation will be explained by 6 (?, ?,. The set target vortex 1 piece is compared with the 7.-1 degree deviation detector 3 to find the l temperature deviation corresponding to the air conditioner negative A Wf, and the according to'
The 71% dynamic compression rock compression rotational speed IW is determined by the relationship shown in the corresponding example shown in the seventh area. The intermittent control signal generator 5 compares the levels of the 111ii+1 degree deviation signals, and as shown in the example shown in Fig. 8, seven snow vehicles exceeding a certain level are given a driving command, while those below a certain level are given a driving command. A stop command is issued. The speed control signal comparison selector 6 determines that the output No. 8 of the intermittent control No. 1g generator 5 is the operation command.
is the speed/1 number generator 40 torque compressor rotation l1 (TK speed (No. 11 output is sent to 111. dynamic compressor 7, and the above intermittent control Iha month output 41: output number i of device 5 is stopped. Whether it is a command, the electric compressor rotational speed signal output of the phantom speed signal generator 4 is cut, a stop signal is sent to the electric compressor 7, and in this way, the electric compressor 7id and the speed control signal comparison selector 6 are It is operated according to the output signal.

FIG. 7 shows an example of how the speed signal corresponds to the temperature deviation of the speed Ih generator 4 in FIG. )1, the minimum rotation speed N and maximum rotation speed N
However, when the 7:m degree deviation is larger than D4 and the maximum rotation speed N4 is given, case j1,
The maximum rotation speed N4 until the temperature deviation falls below the predetermined value D3.
It shows that it holds. In Figure 7, coordinate point (1)
+, N), (D4.

N4) is not necessarily ii! There is no need to connect with a line,
The line may be other than a straight line depending on the operating characteristics and control goals of the air conditioner. However, there is no problem even if the predetermined value (fm, D3 may be a value as shown in FIG. 7, and it is between 1 and D2).

FIG. 8 shows an example of how the operation command corresponds to the flow rate deviation of the intermittent control generator 5 in FIG. 6, and the temperature deviation is D2.
When the temperature deviation becomes too large, an operation command is issued, and when the temperature deviation gradually decreases to Dl, a stop command is issued at that moment, and as long as the temperature deviation remains below DI, it continues to rise until it exceeds D2. ,■) Indicates that a driving command is generated the moment the value exceeds 2.

FIG. 9 shows another embodiment of the invention, one of the previous embodiments.
No. 3 and 192 are made to match.

In the period from (1) to (D2), the minimum speed signal N is generated to improve the operation rate of the electric compressor at low speeds when the load is small.

〔Effect of the invention〕

As stated above, when the electric compressor is operated at variable speeds above the minimum speed N, and the air conditioning load is heavy and the electric compressor is operated at the maximum speed N4,
By continuing to operate at maximum speed when the air conditioning load is below a predetermined value, the electric compressor has the advantages of variable speed operation, improving comfort, reducing operating power, and extending the life of the equipment. An improved sense of comfort can be achieved by improving the start-up during heating and cooling.

[Brief explanation of drawings]

Figure 1 is a relationship diagram between dynamic compressor rotation speed and heating capacity, Figure 2 is a relationship diagram between electric compressor rotation speed and cooling (heating) efficiency, and Figure 3 is an electric compressor relationship diagram. 4 and 5 are diagrams showing an example of room temperature control using the present Komei method and the conventional method, and FIG. 6 is a diagram illustrating an example of the air conditioner according to the present invention. Block diagram, Figure 7 is an example of the correspondence between the temperature deviation of the speed signal generator in Figure 6 and the electric compressor rotation speed, Figure 8 is the temperature deviation and operation of the intermittent control No. h generator in Figure 6. FIG. 9, a diagram showing a correspondence example of stop commands, is a diagram illustrating another embodiment of the present invention. 1... Indoor temperature detector, 2... Indoor target humidity setting device, 3... Hot water temperature deviation detector, 4... Speed signal generator,
5... Intermittent control signal generator, 6... Speed control signal comparison and selection device, 7... Electric compressor 1, 8... Control command means. 9... Sky 1st (2) Gal O"b I'/l N3
~ 4' [Dynamic pressure fallout same payment anzu (boar zI2] Electric pressure? Ii o (mouth inside l ( 312) D・D, Warm Pressure L 9th Mouth 0″′ Atsushi y hammer Δihri 1
Continued from page 1 0 Inventor: Yasuo Hosoda 800 Tomita, Ohira-cho, Shimoga-gun, Tochigi Prefecture Hitachi, Ltd. Tochigi Factory 2 Name of the invention Air conditioner 3.・ 1 temple 3'1 applicant +, "・l 171jll14 ・t, ・
'tl It r't', 'Shi1
Work place 4, agent 11 between 11i i'l'
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(1,,) ,-・'Chokoichi' J2 Fern °I1 1.7 oath ,・1 3, on page 6, line 19, it says "is composed", but [ga, 4-6
The speed signal generating means 10 is configured as follows. 4. Amend Figure 6 of the drawings as shown in the attached sheet. 2, Claim 1 A refrigeration cycle comprising a compressor for compressing refrigerant and a speed control drive unit for driving the compressor, a tlj Nb iso, a room 1 heat exchanger, and an indoor heat exchanger. Yotsu-C An air conditioner for air conditioning a room includes an air conditioning load detection means for detecting an air conditioning load, a means for determining the magnitude of the air conditioning load, and generating an operation or stop signal for the electric motor according to a predetermined hysteresis. The above electric power due to increase in load! t II Generates a speed signal for the electric motor that increases the minimum speed N of one machine to the maximum speed N4, and generates a speed signal for the motor that includes - 2. J) An air cylinder 11 device having a speed signal generating means that operates to continue generating the maximum speed signal N4 during the time when the speed decreases to 3.゜

Claims (1)

[Claims] Detects air conditioning load in an air conditioner that air-conditions a room using a refrigeration cycle that includes a compressor for compressing refrigerant and a speed control drive unit that drives the compressor. an air conditioning load detecting means; a series control signal generating means for determining the magnitude of the air conditioning load and generating a signal to stop the electric motor from operating or stopping according to a predetermined hysteresis; On the other hand, the motor speed signal e'r13 increases at a maximum speed N4-1 in a non-decreasing relationship from the minimum speed N of the electric motor,
When the maximum speed signal is generated, the maximum speed signal continues to be generated. After that, when the air conditioning load falls below a predetermined value, the previous MLE'? a speed signal generating means that operates to generate a speed signal according to the m'J load, generates a stop or speed change signal for the electric motor from the intermittent control signal and the speed signal, and supplies the signal to the speed control drive section of the electric motor. An air conditioner characterized by being equipped with a control command means.