JP2004068668A - Compressor control device for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control a compressor to be operated with low noises during stopping an engine. <P>SOLUTION: In a vehicular air-conditioner 8 which has the compressor 41 mounted on a hybrid vehicle with a vehicle driving engine 4 and a vehicle driving motor 3 and adapted to be driven by a IPM motor 11, an air-conditioner ECU 10 outputs a rotating speed command value for the IPM motor 11 to a control part 14 of an inverter device, outputs a normal mode signal during operating the engine 4 and outputs a low noise mode signal during stopping the engine 4. The control part 14 executes the maximum torque control when receiving the normal mode signal and executes weak field control when receiving the low noise mode signal. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a compressor control device for a hybrid vehicle mounted on a hybrid vehicle such as a hybrid vehicle including a vehicle driving engine and a vehicle driving motor.
[0002]
[Prior art]
A hybrid vehicle is equipped with an internal combustion engine such as a gasoline engine or a diesel engine and an electric motor operated by electricity as power sources. When the engine efficiency is low such as when starting or running at low speed, the engine is not used. Stop and run with the power of the electric motor with excellent low-speed torque. In this way, it is attractive that the hybrid vehicle achieves low fuel consumption, keeps noise low when the engine is stopped, and keeps the interior of the vehicle quiet.
[0003]
In a hybrid vehicle, it has been proposed to employ a compressor using an electric motor as one of driving sources so that the air conditioner can be operated even when the engine is stopped. According to such a configuration, it is not necessary to drive the engine only to operate the compressor, and fuel efficiency can be improved.
[0004]
[Problems to be solved by the invention]
However, if the compressor is driven by the electric motor while the engine is stopped in the hybrid vehicle, there is a problem that the noise of the compressor impairs the quietness of the vehicle interior.
[0005]
The present invention has been made in view of the above problems, and has as its object to provide a hybrid vehicle compressor control device that controls a compressor to operate with low noise while an engine is stopped.
[0006]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided an air conditioner mounted on a hybrid vehicle having a vehicle drive motor and a vehicle drive engine as drive sources. By controlling the voltage applied to the compressor motor when driven by the compressor motor, one of the above, the number of rotations of the compressor motor is controlled. At this time, the compressor motor is controlled in the first mode when it is detected that the vehicle driving engine is operating, and the compressor motor is controlled in the first mode when it is detected that the vehicle driving engine is not operating. Control is performed in the second mode in which the compressor motor is driven with lower noise than in the first mode. In this way, by controlling the compressor motor to operate with low noise while the engine is stopped, quietness in the vehicle compartment while the engine is stopped can be maintained.
[0007]
Further, in the case of a vehicle having high soundproof performance in the vehicle interior, the compressor control device for a hybrid vehicle detects that the vehicle drive engine is not in the operating state, and reduces the rotational speed of the compressor. The compressor motor may be controlled in the second mode when it is detected that the rotation speed is half or more of the maximum rotation speed. As described above, the compressor motor is controlled in the second mode only when the engine is stopped and the noise level of the compressor is high, and when the noise level of the compressor is not so high even when the engine is stopped, the compressor motor is controlled in the first mode. This makes it possible to drive the compressor motor more efficiently without impairing the quietness of the cabin when the engine is stopped.
[0008]
When the compressor motor is an AC motor, the hybrid vehicle compressor control device is configured to execute the field weakening control when controlling the compressor motor in the second mode. Good. In this way, when the compressor motor is subjected to the field weakening control, the efficiency is slightly reduced as compared with the case where the compressor motor is controlled to be most efficiently driven at the target rotation speed. The cogging torque of the motor, which is one factor of the noise of the motor, is reduced, and as a result, the noise from the compressor is reduced. In this way, it is possible to reduce the noise from the compressor when the engine is stopped without significantly reducing the efficiency of the motor.
[0009]
Further, when the hybrid vehicle compressor control device controls the AC motor in the first mode, it is preferable to control the rotation speed of the compressor motor by maximum torque control. In this way, by controlling the motor to be driven efficiently while the engine is operating, the hybrid vehicle can be controlled even when the efficiency is slightly reduced in order to suppress noise from the compressor when the engine is stopped. Low fuel consumption can be maintained.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
A hybrid vehicle compressor control device according to one embodiment of the present invention is incorporated in an air conditioner mounted on a hybrid vehicle. FIG. 1 shows the overall configuration of this air conditioner. The hybrid vehicle 1 includes a vehicle driving motor 3 driven by electric power and a vehicle driving engine 4 which is an internal combustion engine using gasoline or the like as a power source for generating a driving force. Under the control of the hybrid ECU 7, the vehicle travels only by the driving force from the motor 3 when starting and traveling at low speed, and travels using the driving force from both the engine 4 and the motor 3 during normal traveling. Specifically, during normal running, the driving force from the engine 4 is divided into two paths, one of which is to directly drive the wheels 5 and the other of which is to drive the generator 6 to generate power. The generated electric power is used to drive the motor 3 to assist the driving force of the wheels 5, and is converted into DC by the inverter 60 and then stored in the battery 2.
[0011]
The air conditioner 8 includes an air conditioner unit 9 for air-conditioning the cabin of the hybrid vehicle 1 and an air conditioner ECU 10 for controlling devices constituting the air conditioner unit 9. The air conditioner 8 always keeps the temperature in the cabin at a set temperature. It is an automatic air conditioner that automatically controls as follows.
[0012]
The air-conditioning unit 9 is arranged on the front side of the vehicle interior to form an air passage for guiding conditioned air into the vehicle interior, a centrifugal blower unit 30 for sending air in the air-conditioning duct 20, and an air-conditioning duct 20. The cooling system includes a refrigeration cycle 40 for cooling the air flowing through the air conditioning duct 20 and cooling the air flowing through the air conditioning duct 20.
[0013]
An inside / outside air switching box is provided at the most upstream side of the air flow in the air conditioning duct 20, and has an inside air suction port 21 and an outside air suction port 22. An inside / outside air switching damper 23 is rotatably mounted inside the suction ports 21 and 22. The inside / outside air switching damper 23 is driven by an actuator (not shown) such as a servo motor, so that the inside air / outside air switching damper 23 is driven. The suction port mode is switched between an inside air circulation mode in which only the suction port 21 is opened and an outside air introduction mode in which only the outside air suction port 22 is opened.
[0014]
An air outlet switching box is provided at the most downstream side of the air flow in the air conditioning duct 20, and a defroster (DEF) opening, a face (FACE) opening, and a foot (FOOT) opening are formed. Ducts are connected to these openings, respectively. At the most downstream end of these ducts, a defroster (DEF) outlet 24 for blowing air-conditioned air toward the inner surface of the windshield of the vehicle, and the upper body of the occupant A face (FACE) outlet 25 that blows out conditioned air toward the vehicle and a foot (FOOT) outlet 26 that blows out conditioned air toward the feet of the occupant are open. Inside the air outlets 24 to 25, air outlet switching dampers 27 to 29 are rotatably mounted, and these are driven by actuators (not shown) such as servo motors, respectively, so that they can enter the vehicle interior. The air outlet is switched to one of a face (FACE) mode, a bilevel (B / L) mode, a foot (FOOT) mode, a foot differential (F / D) mode, and a defroster (DEF) mode.
[0015]
The blower unit 30 includes a centrifugal fan 31 rotatably housed in a scroll case integrally formed with the air conditioning duct 20, and a blower motor 32 for driving the centrifugal fan 31 to rotate. The control of the rotation speed (blowing amount) of the centrifugal fan 31 is performed by controlling the voltage applied to the blower motor 32 via the blower drive circuit 33.
[0016]
The refrigeration cycle 40 includes an electric compressor 41 for compressing the refrigerant, a condenser 42 for condensing and liquefying the compressed refrigerant, a receiver 43 for separating the condensed and liquefied refrigerant into gas and liquid and flowing only the liquid refrigerant downstream, and decompressing and expanding the liquid refrigerant. It comprises an expansion valve 44, an evaporator 45 for evaporating and evaporating the decompressed and expanded refrigerant, a cooling fan 46 for blowing outside air to the condenser 42, and a refrigerant pipe for connecting these. The condenser 42 is disposed in a place where the traveling wind generated when the vehicle 1 travels is easily received, and performs outdoor heat exchange between the refrigerant flowing therein and the outside air blown by the cooling fan 46 and the traveling wind. It is an exchanger. The evaporator 45 is an indoor heat exchanger that is disposed in the air conditioning duct 20 so as to cover the entire air passage, and cools and dehumidifies the air passing therethrough.
[0017]
The cooling water circuit 50 circulates cooling water (warm water) heated by a water jacket of the vehicle driving engine E by a water pump (not shown), and has a heater core 51 therein. The heater core 51 heats the conditioned air by performing heat exchange between the engine cooling water and the conditioned air. The heater core 51 is disposed downstream of the evaporator 45 in the air duct 20 so as to partially block the air passage. An air mix damper 52 is rotatably mounted in the vicinity of the heater core 51. The air mix damper 52 is driven by an actuator (not shown) such as a servomotor, and the amount of air passing through the heater core 51 is determined by its stop position. The temperature of the air blown into the vehicle cabin is adjusted by adjusting the ratio of the amount of air bypassing the heater core 51 to the amount of air bypassing the heater core 51.
[0018]
The compressor 41 has a built-in permanent magnet (IPM) synchronous motor (compressor motor) 11 that drives a compression mechanism therein by receiving electric power from the battery 2. The IPM motor 11 is inverter-controlled by an inverter device 12. The inverter device 12 includes a DC / AC conversion unit 13 having a plurality of switching elements (not shown), and a control unit 14 for controlling on / off operations of the switching elements. The IPM motor 11 is driven by an AC voltage from the battery 2 applied via the DC / AC converter 13.
[0019]
The air conditioner ECU 10 is disposed in a vehicle interior, and a microcomputer including a CPU, a ROM, a RAM, and the like (not shown) is provided therein. To the air conditioner ECU 10, switch signals from switches on an air conditioner operation panel 15 provided on the front surface of the vehicle compartment and sensor signals from various sensors (not shown) are input. Here, the switch signal is an air conditioner operation signal from an air conditioner switch, a set temperature signal indicating a temperature set by an occupant, and the like. An outside air temperature sensor for detecting the air temperature, a solar radiation sensor for detecting the amount of solar radiation irradiated into the vehicle interior, an evaporator outlet temperature sensor for detecting the air temperature immediately after passing through the evaporator 45, and a temperature of the cooling water flowing into the heater core 51. A water temperature sensor for detecting the vehicle speed, a vehicle speed sensor for detecting the traveling speed of the vehicle, and the like. Sensor signals from these sensors are A / D converted by an input circuit (not shown) in the air conditioner ECU 10 and then input to the microcomputer.
[0020]
When the ignition switch of the vehicle 1 is turned on, the air conditioner ECU 10 is operated by supplying DC power from the battery 2. FIG. 2 is a flowchart illustrating a procedure of a control process executed by the air conditioner ECU 10. When the ignition switch is turned on and this routine is started, first, in step 100, initialization is performed. Subsequently, a switch signal is read from each switch in step 110, and a sensor signal from each sensor is read in step 120. Next, in step 130, the current state of the cooling load is determined based on the set temperature, the inside air temperature detected by the inside air temperature sensor, the outside air temperature detected by the outside air temperature sensor, and the amount of solar radiation detected by the solar radiation sensor. Then, the target blowing temperature TAO of the air blown into the vehicle compartment is calculated. Subsequently, in step 140, a blower voltage (voltage applied to the blower motor 32) is determined based on the target blowout temperature TAO. Further, in step 150, the inlet mode is determined based on the target outlet temperature TAO, and in step 160, the outlet mode is determined based on the target outlet temperature TAO. In step 170, the opening of the air mix damper 52 is determined based on the target outlet temperature TAO, the evaporator outlet temperature, the cooling water temperature, and the like.
[0021]
In step 180, a subroutine for compressor control processing is called and executed, thereby determining a target rotation speed of the IPM motor 11 and a mode in which the IPM motor 11 is subjected to inverter control. FIG. 3 is a flowchart showing the procedure of the compressor control process. First, in step 200, based on the target outlet temperature TAO and the evaporator outlet temperature, a target rotation speed of the IPM motor 11 for enabling supply of a refrigerant amount according to the current cooling load is determined. At step 210, it is determined whether or not the engine is operating. If it is determined that the engine is operating, the process proceeds to step 230, where the mode for controlling the IPM motor 11 is determined to be the normal mode. If it is determined in step 210 that the engine is stopped, the process proceeds to step 240, where the mode for controlling the IPM motor 11 is determined to be the low noise mode.
[0022]
Returning to FIG. 2, in step 190, the blower motor 32, the inside / outside air switching damper 23, the air outlet switching dampers 27 to 29, the actuators (not shown) for driving the air mix damper 52, and the blower driving circuit 33 A control signal for controlling these to the target values calculated in steps 140 to 170 is output. Further, a rotation speed command signal S1 indicating the target rotation speed of the IPM motor 11 determined in step 180 and a control mode signal S2 indicating the inverter control mode are output to the control unit 14 of the inverter device 12.
[0023]
When receiving the normal mode signal as the control mode signal from the air conditioner ECU 10, the control unit 14 of the inverter device 12 executes the maximum torque control for determining the target current value so that the target rotation speed can be obtained with the minimum current as follows. I do. In general, in the case of an AC motor, the motor current includes the exciting current, so that the torque is not proportional to the current. Therefore, the motor current is separated into a d-axis current (excitation current component) and a q-axis current (torque current component) and controlled independently. Since the IPM motor 11 is an AC motor having a reverse saliency, not only the magnet torque but also the reluctance torque can be used. Therefore, assuming that the current value is constant, as shown in FIG. 4A, the maximum torque is such that the current phase β determined by the d-axis component and the q-axis component is in the range of −45 ° <β <0 °. There is a point to be obtained, and torque can be obtained most efficiently by controlling the current vector to a phase (optimal phase) corresponding to this point.
[0024]
FIG. 4B is a diagram illustrating an example of a relationship between a current value and a torque in the IPM motor 11. In FIG. 4B, the maximum torque / current curve is a curve obtained by connecting points where the current value (consisting of the d-axis component Id and the q-axis component Iq) is minimum on each constant torque curve. In the maximum torque control, a current value corresponding to a point on the maximum torque / current curve is determined as a target current value. Specifically, the load torque corresponding to the target rotation speed is determined from the load rotation speed-load torque characteristic of the compressor 41, and the intersection of the constant torque curve and the maximum torque / current curve corresponding to the load torque is determined as the target current. Selected as value.
[0025]
For example, when the load torque corresponding to the target rotation speed is 3 Nm, the current value at the point P is determined as the target current value. That is, the value of the d-axis component Id at the point P is set as the target value of the d-axis current, and the value of the q-axis component Iq is set as the target value of the q-axis current. A d-axis voltage target value and a q-axis voltage target value are determined based on the current target value and the target rotation speed. By such control, a motor torque corresponding to the load torque corresponding to the target rotation speed can be obtained with the minimum current. When the actual load torque is smaller than the motor torque, the rotation of the IPM motor 11 is accelerated, and when the actual load torque is larger than the motor torque, the rotation of the IPM motor 11 is reduced. When the actual load torque becomes equal to the motor torque in this way, the IPM motor 11 rotates at a rotation speed (a target rotation speed) corresponding to the load torque.
[0026]
On the other hand, when receiving the low noise mode signal as the control mode signal from the air conditioner ECU 10, the control unit 14 performs the field weakening control for controlling the IPM motor 11 to the target rotational speed while maintaining the induced voltage at the predetermined value. Conventionally, field weakening control is intended to further increase the number of revolutions after the voltage reaches saturation, and when performing field weakening control for this purpose, the induced voltage is based on the actual voltage limit value or current limit value. The induced voltage is controlled so as to keep the derived induced voltage limit value. FIG. 5 is a diagram illustrating an example of the relationship between the current value and the torque in the IPM motor 11 and the relationship between the current value and the rotation speed when the field weakening control is performed. In the field-weakening control, in order to keep the induced voltage at a constant limit value, when the current values (d-axis current value Id and q-axis current value Iq) are determined, the rotation speed is thereby limited to a specific rotation speed. FIG. 5 shows an example of a constant rotation speed curve (ellipse) connecting points corresponding to a specific rotation speed.
[0027]
Specifically, in the field-weakening control, first, a load torque corresponding to a target rotation speed is obtained from a rotation speed-load torque characteristic of the load in the compressor 41, and a constant torque curve corresponding to the load torque and a target rotation speed in FIG. Is selected as the target current value. If there are a plurality of such intersections, the point with the smallest current value is selected. For example, the target rotation speed is 5480 min.^{− 1}When the load torque is 3 Nm, the current value at the point R is set as the target current value. As described above, according to the field weakening control, the d-axis current is increased in the negative direction to weaken the magnetic flux, so that the rotation speed can be increased even after the voltage reaches saturation.
[0028]
Generally, when the motor is controlled by the field-weakening control, the cogging torque is reduced due to the decrease in the magnetic flux, thereby reducing the noise. Focusing on this, the present embodiment employs field weakening control as a control method in the low noise mode. However, if the induced voltage is controlled to the actual induced voltage limit value as in the conventional field-weakening control, a large current is required to obtain a low rotation speed. The rotation speed is limited by the current limit value. Conventional field-weakening control is used to further increase the number of revolutions after the voltage reaches a saturation state, so there is no problem even if there is a limit on the minimum number of revolutions obtained by this control. Since the field-weakening control is adopted as the control in step (1), it must be possible to obtain the rotation speed in the operating range of the compressor 41 by this control. When the control is performed such that the induced voltage is maintained at the actual induced voltage limit value, if a low rotation speed among the rotation speeds in the operating range of the compressor 41 cannot be obtained, such a low rotation speed is set to the range of the current limit value. In order to obtain a value within the range, a value smaller than the actual induced voltage limit value must be set as the induced voltage limit value, and control must be performed to maintain the induced voltage at this value.
[0029]
Therefore, in this embodiment, in the field-weakening control executed as control in the low noise mode by the control unit 14 of the inverter device 12, the induced voltage limit value is set in advance based on the operating range of the compressor 41, and the induced voltage limit value is induced. The target current values (d-axis current target value Id and q-axis current target value Iq) are determined so as to maintain the voltage. Specifically, similarly to the above-described conventional field weakening control, a current value at which a target rotation speed is obtained when the induced voltage is fixed at the set induced voltage limit value (on a constant rotation speed curve corresponding to the target rotation speed). ), A current value at which a motor torque corresponding to the load torque is obtained (intersection with a constant torque curve corresponding to the load torque) is selected as the target current value. A d-axis voltage target value and a q-axis voltage target value are determined based on the target current value and the target rotation speed. According to such field-weakening control, the noise from the compressor 41 can be reduced although the efficiency is slightly reduced as compared with the above-described maximum torque control.
[0030]
The control unit 14 outputs a control signal to the DC / AC conversion unit 13 for controlling the voltage applied to the IPM motor 11 to the determined target value. Thus, the IPM motor 11 is driven at the target rotation speed by the AC voltage applied through the DC / AC converter 13.
[0031]
As described above, in the present embodiment, the maximum torque control is executed so that the IPM motor 11 can be efficiently driven at the target rotation speed while the engine is operating, and the IPM motor 11 is controlled while the engine is stopped while suppressing noise. Field weakening control is performed so that can be driven at the target rotation speed. As a result, in the hybrid vehicle, it is possible to maintain quietness in the vehicle compartment when the engine is stopped without significantly increasing the fuel efficiency.
[0032]
The control unit 14 of the air conditioner ECU 10 and the inverter device 12 according to the present embodiment corresponds to the control means of the present invention. Further, the normal mode of the present embodiment corresponds to the first mode of the present invention, and the low noise mode corresponds to the second mode of the present invention.
[0033]
(2nd Embodiment)
In the first embodiment, the control mode is determined based only on whether the engine 4 is operating or not. In the second embodiment, it is further determined whether the rotation speed of the compressor 41 is less than half of the maximum rotation speed. The control mode is determined on the basis of the above. As shown in FIG. 6, in a vehicle having a high soundproofing performance in the vehicle compartment, the noise level in the vehicle compartment increases even if the rotational speed of the compressor 41 increases in a range of less than half of the maximum rotational speed (less than 3500 rpm in FIG. 6). Experiments have shown that there is little. Therefore, if the rotation speed of the compressor 41 is less than half of the maximum rotation speed even when the engine is stopped, the quietness in the vehicle compartment is not impaired even if the normal control is performed.
[0034]
Therefore, in the second embodiment, the compressor control process is executed as shown in FIG. This compressor control process is called as a subroutine by the air conditioner control process shown in FIG. 2, as in the first embodiment. First, in step 300, the target rotation speed of the IPM motor 11 is determined based on the target outlet temperature TAO and the evaporator outlet temperature. At step 310, it is determined whether or not the engine is operating. If it is determined that the engine is operating, the process proceeds to step 330, where the mode for controlling the IPM motor 11 is determined to be the normal mode. If it is determined in step 310 that the engine is stopped, the process proceeds to step 320, where the target rotation speed Nc of the compressor 41 (IPM motor 11) obtained in step 300 is determined.^tIs greater than or equal to half of the maximum rotation speed Ncmax. If the rotation speed Nc is equal to or more than half of the maximum rotation speed Ncmax, the process proceeds to step 340, where the mode for controlling the IPM motor 11 is determined to be the low noise mode. In step 320, the target rotation speed Nc of the compressor 41^tIs smaller than half of the maximum rotation speed Ncmax, the routine proceeds to step 330, and the mode for controlling the IPM motor 11 is determined to be the normal mode.
[0035]
The target rotational speed and the inverter control mode determined by the compressor control process as described above are transmitted from the air conditioner ECU 10 to the control unit 14 of the inverter device 12 as the rotational speed command signal S1 and the control mode signal S2, as in the first embodiment. Each is output. The control unit 14 executes the maximum torque control when receiving the normal mode signal as the control mode signal S2, and executes the field weakening control when receiving the low noise mode signal as the control mode signal S2.
[0036]
According to the present embodiment, when the level of the noise from the compressor 41 in the vehicle compartment is not so high even when the engine is stopped, the quietness in the vehicle compartment when the engine is stopped is maintained by executing the maximum torque control instead of the field-weakening control. However, it is possible to drive the IPM motor 11 more efficiently.
[0037]
The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the invention described in the claims.
[0038]
In the above embodiment, when the control unit 14 of the inverter device 12 receives the normal mode signal as the control mode signal S2 from the air conditioner ECU 10, the control is performed to the strict optimal current phase according to the current value. 4 (B), the angle between the line connecting the point on the maximum torque / current curve and the origin and the Iq axis) slightly changes depending on the current value, but does not change so much. The phase may be controlled to βopt. That is, the d-axis current target value Id and the q-axis current target value Iq are determined such that a motor torque corresponding to the load torque corresponding to the target rotation speed is obtained and the current phase β matches the optimum phase βopt. You may do so. Thus, even if the maximum torque control of the above embodiment is simplified, the efficiency is not greatly reduced.
[0039]
In the above embodiment, the control unit 14 of the inverter device 12 receives the rotation speed command signal S1 indicating the target rotation speed and the control mode signal S2 from the air conditioner ECU 10 and controls the rotation speed of the IPM motor 11 in an open control system. Although an example has been shown, the control unit 14 may fetch the actual rotation speed information of the IPM motor 11 and control the IPM motor 11 to the target rotation speed by feedback control.
[0040]
In the second embodiment, when the engine is stopped and the rotation speed of the compressor 41 is half or more of the maximum rotation speed, that is, when the engine is stopped and the noise level from the compressor 41 is high, the low noise In the case where the IPM motor 11 is controlled in the mode, the condition that the vehicle 1 is stopped or running at a low speed is added thereto, and the level of the noise from the compressor 41 becomes higher than the running sound of the vehicle 1 The IPM motor 11 may be controlled only in the low noise mode. Even in this case, similarly to the second embodiment, it is possible to efficiently drive the IPM motor 11 while maintaining quietness in the vehicle interior when the engine is stopped.
[0041]
In the above-described embodiment, the IPM motor 11 is used as the motor for driving the compressor 41. However, other types of motors such as an AC motor or a DC motor can be used for driving the compressor 41. However, similarly to the above embodiment, the field weakening control can be adopted as the control in the low noise mode only in the case of the AC motor. In the case of a DC motor, for example, in the normal mode, the motor is controlled to the target rotation speed, and in the low noise mode, if it is not so strictly required that the motor is driven at the target rotation speed, the target rotation speed is set. Control such as reducing the number to a predetermined level may be performed. As a control method in the normal mode when an AC motor other than the IPM motor is used, an efficient control method according to the type of the motor may be employed. As in the above-described embodiment, the maximum torque control can be adopted as the control in the normal mode only in the case of a motor (such as a reluctance motor) having saliency (or reverse saliency).
[0042]
For example, in the case of a surface permanent magnet (SPM) synchronous motor having no saliency, reluctance torque cannot be used, and only magnet torque is used. That is, in this case, since the d-axis current does not contribute to the generation of torque, the maximum torque can be obtained when the point B in FIG. 4A, that is, when the current phase is 0 °. Therefore, in the case of such an SPM motor, it is efficient to perform control so as to always keep Id = 0.
[0043]
In the above embodiment, the IPM motor 11 for driving the compressor 41 is built in the compressor 41, but the IPM motor 11 may be installed outside the compressor 41. In the above embodiment, the compressor 41 is an electric compressor driven only by a motor, but may be a hybrid compressor using the vehicle drive engine 4 and the compressor motor as drive sources.
[0044]
In the above embodiment, the present invention is applied to an automatic air conditioner that performs automatic control by the air conditioner ECU 10, but the present invention may be applied to a manual air conditioner that is controlled by manual operation.
[0045]
In the above-described embodiment, the present invention is applied to the vehicle air conditioner including the heater core 51. However, the discharge gas refrigerant (hot gas) of the compressor is directly introduced into the condenser of the refrigeration cycle, and the condenser radiates heat from the gas refrigerant to the conditioned air. By doing so, the present invention can be applied to a vehicle air conditioner that obtains a heating function. In the above embodiment, the present invention is applied to an air-mix type air conditioner for a hybrid vehicle in which cold air is reheated by a heater core 51. However, a reheat type vehicle in which the amount of hot water supplied to the heater core is adjusted by a flow control valve. The present invention may be applied to an air conditioner for home use.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating an overall configuration of a hybrid vehicle air conditioner in which a compressor control device according to a first embodiment of the present invention is incorporated.
FIG. 2 is a flowchart showing a procedure of a control process executed by an air conditioner ECU shown in FIG.
FIG. 3 is a flowchart showing a procedure of a compressor control process executed in step 180 shown in FIG. 2; (1st Embodiment)
4A is a diagram showing an optimum phase of a current supplied to a motor used for driving a compressor, and FIG. 4B is a diagram showing a maximum phase executed in a normal mode by a control unit of the inverter device shown in FIG. FIG. 4 is an explanatory diagram of torque control.
FIG. 5 is an explanatory diagram of a field weakening control executed in a low noise mode by a control unit of the inverter device shown in FIG. 1;
FIG. 6 is a diagram showing the relationship between the number of revolutions of the compressor of the vehicle air conditioner and the noise level in the vehicle cabin.
FIG. 7 is a flowchart showing a procedure of a compressor control process executed in step 180 shown in FIG. 2; (2nd Embodiment)
[Explanation of symbols]
1 Hybrid car
2 Battery
3 Vehicle drive motor
4 Vehicle drive engine
8 air conditioner for hybrid vehicles
9 air conditioning unit
10 air conditioner ECU
11 Motor for compressor
12 inverter device
13 DC / AC converter of inverter device
14 Control unit of inverter device
41 compressor

Claims (4)

An air conditioner (8) mounted and used in a hybrid vehicle (1) having a vehicle drive motor (3) and a vehicle drive engine (4) as drive sources includes a compressor (41) that compresses and discharges refrigerant. The compressor motor (11), which is one of the driving sources for driving, is applied to the compressor motor (11) when the compressor (41) is driven by the compressor motor (11). A compressor control device for a hybrid vehicle, comprising control means (10, 14) for controlling the number of revolutions by controlling the voltage applied to the compressor.
The control means (10, 14) controls the compressor motor (11) in a first mode when detecting that the vehicle driving engine (4) is in an operating state, and controls the vehicle driving engine ( And 4) controlling the compressor motor (11) in a second mode in which the compressor motor (11) is driven with lower noise than in the first mode when detecting that the compressor motor (11) is not operating. Control device for hybrid vehicles. When the control means (10, 14) detects that the vehicle drive engine (4) is not in an operating state and detects that the rotational speed of the compressor (41) is half or more of the maximum rotational speed. The compressor control device for a hybrid vehicle according to claim 1, wherein the compressor motor (11) is controlled in the second mode. The compressor motor (11) is an AC motor, and when the control means (10, 14) controls the compressor motor (11) in the second mode, the compressor motor (11) is controlled by field weakening control. The compressor control device for a hybrid vehicle according to claim 1 or 2, wherein the rotation speed is controlled. When the control means (10, 14) controls the compressor motor (11) in the first mode, the control means (10, 14) controls the rotation speed of the compressor motor (11) by maximum torque control. The compressor control device for a hybrid vehicle according to claim 3.

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