JP2015193283A - Control driving device for motor compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control driving device for a motor compressor, the device capable of suppressing generation of background noise.SOLUTION: A control driving device for a motor compressor includes: a motor compressor provided with a built-in variable speed motor and compressing an air conditioning coolant; background noise detection means for detecting the background noise of a vehicle; and an inverter for controlling a rotation number of the motor compressor. The rotation number of the variable speed motor is designed to be controlled so that the rotation number of the motor compressor follows a control target value in response to the operational state of air conditioning by a refrigeration cycle. For a rotation number's rate of change, which is a rate of rotation number's change in a prescribed time, during the following up, an upper limit value of the rotation number's rate of change corresponding to the background noise is set.

Description

  The present invention relates to a control drive device for an electric compressor, and in particular, background noise (including background noise related to vehicle speed, a radiator fan that is a fan that sends air to a radiator or a condenser fan that is a fan that sends air to a condenser). The present invention relates to a control drive device for an electric compressor which is intended to be suppressed.

  Various types of control of the electric compressor have been conventionally proposed (for example, see Patent Document 1). Hereinafter, a conventional example of control of the electric compressor will be described with reference to FIG. As shown in FIG. 4, in step SB01, it is determined whether or not the air conditioner switch is OFF. If the air conditioner switch is OFF, the process proceeds to step SB02. If the air conditioner switch is ON, the process proceeds to step SB03.

  In step SB02, 0 is set to the designated rotational speed of the compressor.

  In step SB03, the evaporator determines whether the temperature is 1 ° C. or less. If the evaporator determines that the temperature is 1 ° C. or lower, the process proceeds to step SB02. When it is determined that the evaporator is not 1 ° C. or less, the process proceeds to step SB04.

  In step SB04, the rotation speed of the compressor is calculated by PI control calculation.

  Here, the number of rotations is obtained by the following PI control equation.

Number of revolutions = (actual evaporating temperature−target evaporating temperature) × P + ∫ (actual evaporating temperature−target evaporating temperature) × I
The actual evaporator temperature in the above formula is the actual evaporator temperature, and the target evaporator temperature is the target evaporator temperature.

  In step SB05, the rotational speed difference is calculated. That is, the rotational speed difference = the previous rotational speed (previous rotational speed) −the rotational speed (calculated value).

  In step SB06, it is determined whether or not the rotational speed difference is larger than 2000. If it is determined that the rotational speed difference is greater than 2000, the process proceeds to step SB07. If it is determined that the rotational speed difference is 2000 or less, the process proceeds to step SB08.

  In step SB07, the value of the previous rotation speed -2000 is set as the designated rotation speed of the compressor.

  In step SB08, the designated rotational speed = rotational speed (calculated value) is set.

  In step SB09, inverter rotation speed control is performed.

  In step SB10, the designated rotational speed is set as the previous rotational speed.

  As shown in FIG. 5A, the temperature of the evaporator usually decreases with time. Then, as shown in FIG. 5B, when the rotational speed of the compressor is lowered with time, as shown in B1 to B4, the sudden rotational speed decreases.

Japanese Patent No. 3477759

  However, there is a problem that the rate of change in the rotation speed of the compressor is larger in the high rotation speed range and the high rotation speed range of the electric compressor, and noise (sound is easily noticeable) due to fluctuations in the rotation speed occurs. is there.

  Accordingly, an object of the present invention is to provide a control drive device for an electric compressor that can suppress the generation of noise by changing the rate of change of the rotational speed in accordance with background noise that changes depending on the vehicle speed or the like. .

  According to the first aspect of the present invention, an electric compressor that incorporates a variable speed motor and compresses a refrigerant for air conditioning, background noise detection means that detects background noise of the vehicle, and the number of revolutions of the electric compressor are controlled. An inverter, and the rotation speed of the variable speed motor is controlled so that the rotation speed of the electric compressor follows the control target value according to the air conditioning operation state by the refrigeration cycle, and a predetermined value is set when the rotation speed is followed. The rotational speed change rate, which is the rate at which the rotational speed changes over time, is provided with an upper limit value of the rotational speed change rate according to the background noise.

  The invention according to claim 2 is characterized in that the upper limit value of the rotational speed change rate is larger as the background noise is larger.

  According to a third aspect of the present invention, the background noise detection means includes a vehicle speed related to background noise, a rotational speed of a radiator fan that sends air to the radiator, or a rotation of a condenser fan that sends air to the condenser. It is characterized by detecting numbers.

  According to the present invention, the generation of noise is suppressed by providing the upper limit value of the rotational speed change rate that changes depending on the vehicle speed.

It is the schematic which shows embodiment of this invention and shows the outline of a control drive device. It is a flowchart which shows embodiment of this invention and shows operation | movement of a control drive device. 1 shows an embodiment of the present invention, where (a) is a characteristic diagram of air temperature that has passed through an evaporator at normal time, and (b) is a characteristic that shows a change in the rotational speed of the compressor when the air temperature has passed through the evaporator. FIG. It is a flowchart which shows a prior art example and shows operation | movement of a control drive device. A conventional example is shown, (a) is a characteristic diagram of the air temperature that has passed through the evaporator in a normal state, (b) is a characteristic diagram that shows a change in the rotational speed of the compressor when the air temperature that has passed through the evaporator is lowered. is there.

  Embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the vehicular cooling device is electrically driven according to the refrigeration cycle S, the speed (background noise) detection means 11 for detecting the speed (background noise) of the vehicle, the detection result of the speed detection means 11, and the like. And a control drive device 10 that controls an inverter 2 that controls the rotational speed of the compressor 1.

  The refrigeration cycle S is generally well-known, and can be briefly described as follows. The electric compressor 1 compresses the gaseous refrigerant into a high-temperature and high-pressure refrigerant, and the condenser 4 cools the high-temperature and high-pressure refrigerant. Thus, the liquid refrigerant is decompressed by the expansion valve 6, and the air passing through the evaporator 7 is cooled by using the heat of vaporization of the decompressed refrigerant. The electric compressor 1 includes an inverter 2 and a variable speed motor 3 driven by the output of the inverter 2.

  The control drive device 10 of the electric compressor 1 controls the rotation speed of the variable speed motor 3 so that the rotation speed of the electric compressor 1 follows the control target value according to the air conditioning operation state by the refrigeration cycle S. Thus, an upper limit value of the rotational speed change rate is set according to the speed (background noise), and the rotational speed change rate, which is the rate at which the rotational speed changes during a predetermined time when the tracking is performed. This will be described below.

  FIG. 2 shows a control flow of the control drive device 10, and this control flow will be described. As shown in FIG. 2, in step SA01, it is determined whether the air conditioner switch (AC-SW) is ON or OFF. If it is determined that the air conditioner switch is ON, the process proceeds to step SA02. If it is determined that the air conditioner switch is OFF, the process proceeds to step SA03.

  In step SA02, the control drive device 10 sets the command rotational speed to zero.

  In step SA03, referring to the detected value, the control drive device 10 determines whether or not the evaporator is 1 ° C. or less. If the evaporator determines that the temperature is 1 ° C. or lower, the process proceeds to step SA02. If it is determined that the evaporator is not below 1 ° C., the process proceeds to step SA04.

  In step SA04, the control drive device 10 calculates the rotational speed of the electric compressor 1 by PI control calculation.

  That is, the rotational speed of the electric compressor 1 is calculated by the following formula.

Number of revolutions = (actual evaporating temperature−target evaporating temperature) × P + ∫ (actual evaporating temperature−target evaporating temperature) × I
The actual evaporator temperature in the above formula is the actual temperature of the evaporator 7, and the target evaporator temperature is the target temperature of the evaporator 7.

  In step SA05, the control drive device 10 calculates the rotational speed difference of the electric compressor 1.

  That is, the rotational speed difference = the previous rotational speed (previous rotational speed) −the rotational speed (calculated value).

  In step SA06, the control drive device 10 determines whether or not the vehicle speed is greater than 60 km / h. If it is determined that the vehicle speed is greater than 60 km / h, the process proceeds to step SA07. If it is determined that the vehicle speed is 60 km / h or less, the process proceeds to step SA08.

  In step SA07, the control drive device 10 sets the change rate to 2000.

  In step SA08, the control drive device 10 determines whether or not the vehicle speed is greater than 20 km / h. If it is determined that the vehicle speed is greater than 20 km / h, the process proceeds to step SA09. If it is determined that the vehicle speed is 20 km / h or less, the process proceeds to step SA10.

  In step SA09, the control drive device 10 sets the rate of change to 500.

  In step SA10, the control drive device 10 sets the rate of change to 100.

  In step SA11, the control drive device 10 determines whether the rotational speed difference is larger than the change rate. If it is determined that the rotational speed difference is greater than the change rate, the process proceeds to step SA12. If it is determined that the rotational speed difference is equal to or less than the change rate, the process proceeds to step SA13.

  In step SA13, the control drive device 10 sets the rotational speed (calculated value) as the designated rotational speed.

  In step SA12, the control drive device 10 sets the value of the previous rotational speed-change rate as the designated rotational speed.

  In step SA14, the inverter controls the rotation speed of the inverter.

  In step SA05, the control drive device 10 sets the indicated rotational speed as the previous rotational speed.

  That is, in the control flow, the upper limit value of the rotational speed change rate is set to be larger as the speed (background noise) is larger. In other words, the upper limit value of the rotational speed change rate is set to be smaller as the speed (background noise) is smaller.

  Accordingly, as shown in FIG. 3A, in normal operation, the temperature of the air that has passed through the evaporator decreases with time. Although the rotation of the electric compressor (compressor) 1 is controlled by a drop in the air temperature that has passed through the evaporator, the upper limit value of the rate of change is changed according to the vehicle speed as described above. Specifically, in the situation where background noise is conspicuous, As shown in FIG. 3 (b), the rotation of the electric compressor (compressor) 1 is a gradual decrease in the rotational speed as indicated by A1 to A4.

  The resolution in the above control is temperature: increments of 0.3 ° C., rotation speed: 1 rpm, temperature range: −10 to 40 ° C., rotation speed: 1000 to 9000 rpm, but suppresses noise caused by fluctuations in the rotation speed due to the difference in resolution. There is also an effect.

  In the control of the above embodiment, the reference speed for changing the upper limit value of the rotation change of the electric compressor (compressor) 1 is set to 60 km / h and 20 km / h, but is not limited thereto. Various factors are taken into consideration.

In the above embodiment, the background noise detection means 11 detects the vehicle speed related to the background noise. However, the background noise detection means 11 is a fan that sends air to the condenser, or the rotation speed of the radiator fan that sends air to the radiator. It may be one that detects the rotational speed of a certain condenser fan.
Is also applicable.

DESCRIPTION OF SYMBOLS 1 Electric compressor 2 Inverter 3 Variable speed motor 4 Capacitor 5 Condenser fan 6 Expansion valve 7 Evaporator 8 Radiator 9 Radiator fan 10 Control drive 11 Speed detection means

Claims (3)

An electric compressor (1) that incorporates a variable speed motor and compresses refrigerant for air conditioning, background noise detection means (5, 9, 11) for detecting background noise of the vehicle, and rotation of the electric compressor (1) An inverter (2) for controlling the number,
The rotation speed of the variable speed motor (3) is controlled so that the rotation speed of the electric compressor (1) follows the control target value according to the air-conditioning operation state by the refrigeration cycle. A control drive device (10) for the electric compressor (1), characterized in that an upper limit value of the rotational speed change rate is set in accordance with the background noise as a rotational speed change rate that is a rate at which the rotational speed changes over time ).   The control drive device (10) for an electric compressor (1) according to claim 1, wherein the upper limit value of the rotational speed change rate is larger as the background noise is larger.   The background noise detection means (5, 9, 11) is a vehicle speed related to background noise, the number of revolutions of a radiator fan that sends air to the radiator, or the number of revolutions of a condenser fan that sends air to the condenser. The control drive device (10) of the electric compressor (1) according to claim 1 or 2, wherein the control drive device (10) is detected.

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