JP2002079826A - Hybrid compressor control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hybrid compressor control device which prevents breakage of an electric motor by preventing a current from exceeding a rated current at starting of the motor. SOLUTION: A hybrid compressor 5 which selects at least an engine 1 for travelling and the electric motor 7 as a driving source, and is driven by the electric motor 7 at the stop of the engine 1 for traveling, is provided with excessive load current preventive means for preventing an excessive load current at starting of the electric motor 7. When the hybrid compressor is provided with a variable capacity mechanism, discharge capacity of the compressor 5 is gradually increased from 0 at starting of the electric motor 7, and when the hybrid compressor is a fixed capacity compressor, voltage supplied to the electric motor 7 is gradually increased from 0 at starting of the electric motor 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a hybrid compressor which is driven by at least a driving engine and an electric motor when the driving engine is stopped.

[0002]

2. Description of the Related Art A control device for a vehicle compressor disclosed in Japanese Patent Application Laid-Open No. 10-236151 aims at reducing the size of an electric motor and improving the mountability of the electric motor on a vehicle. Before driving the compressor, the discharge capacity of the compressor is set to a minimum value to minimize the driving load of the compressor and the driving load of the electric motor.

[0003]

However, in the above-mentioned reference, even if the load on the compressor is minimized, the electric motor for driving the compressor is reduced accordingly, so that the inrush current to the electric motor is reduced to the rated current of the motor. , The electric motor is damaged.

Further, when the motor is started after the engine is stopped (after the compressor is stopped), the pressure in the refrigeration cycle is in an equilibrium state, so that the starting torque of the compressor is increased and the load on the motor is rapidly increased. Therefore, the same problem as in the case described above occurs.

[0005] Therefore, an object of the present invention is to provide a hybrid compressor control device that prevents the electric motor from being damaged by preventing the current at the time of starting the motor from exceeding the rated current.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a hybrid compressor which is driven by the electric motor when the driving engine is stopped, wherein at least the traveling engine and the electric motor are selected as drive sources. Another object of the present invention is to provide an overload current preventing means for preventing an overload current when starting the motor.

[0007] Further, the hybrid compressor includes:
It is preferable that a displacement variable mechanism be provided, and that the overload current prevention means gradually increase the discharge capacity of the compressor from zero or a minimum capacity when the electric motor is started.

Further, the hybrid compressor is a fixed displacement compressor, and the overload current preventing means gradually increases a supply voltage to the electric motor from zero when the electric motor is started. Is desirable.

[0009]

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

In FIG. 1, a traveling engine 1 is a direct-injection engine mounted on, for example, a hybrid vehicle or an idle stop vehicle, and is connected to an air conditioning compressor 5 via a belt 4 mounted on pulleys 2 and 3. I have.
The air conditioning compressor 5 and the traveling engine 1 are connected via an electromagnetic clutch 6.

The air-conditioning compressor 5 is a hybrid compressor that can be driven by an electric motor 7. When the connection with the traveling engine 1 is interrupted by an electromagnetic clutch 76, the electric motor 7 The electric motor 7 is driven by the start of energization.

The air conditioning compressor 5 has a variable capacity mechanism 8 so that the amount of refrigerant flowing through the refrigeration cycle 13 can be changed. The refrigeration cycle 13 is configured at least by the air conditioning compressor 5, the condenser 9, the expansion valve 10, and the evaporator 12 arranged in the air conditioning duct 11.
As the control factor of the variable capacity mechanism 8, for example, the high pressure Pd of the refrigeration cycle 13 detected by the pressure sensor 14 is used. It should be noted that, depending on the type of refrigerant, it is suitable to use the low pressure of the refrigeration cycle 13 as a control factor.

In the above configuration, the traveling engine 1,
A control unit 20 is provided to control the electromagnetic clutch 6, the variable displacement mechanism 8, an air-conditioning control device (not shown), and other control devices. The control unit 20 includes at least a central processing unit (CP)
U), a read-only memory (ROM), a random access memory (RAM), an input / output port (I / O), and the like. The control unit 20 includes a rotational speed Ne of the traveling engine, After the high pressure Pd of the refrigeration cycle 13, the compressor rotation speed Nc, the supply current Im to the electric motor 7, and other heat load signals for air conditioning control are input and processed by a predetermined program, the control signal Is output.

Hereinafter, the control of the hybrid compressor according to the first embodiment of the present invention executed by the control unit 20 will be described with reference to the flowchart shown in FIG.

The hybrid compressor control started from step 100 is periodically started from a main control routine for performing air conditioning control or the like.
It is determined whether or not the rotation speed Ne of the traveling engine 1 is equal to the idling rotation speed Na.
Proceeding to step 120, the compressor discharge capacity Cc is set to 0.
(Destroke), the engine speed Ne is set to 0 in step 130, and the process returns from step 270 to the main control routine.

Then, according to the setting of step 130, the process proceeds from step 110 to step 140 to determine whether or not the engine speed Ne is zero. If it is determined in step 110 that the engine rotation speed Ne is equal to or higher than the idling rotation speed Na, the process proceeds from step 110 to step 140. Proceeding to 150, the compressor discharge capacity C
c, a compressor discharge capacity Cem suitable for driving by the driving engine 1 is set, a timer T described below is reset in step 160, and various setting flags A and B are returned to initial values in step 170, and step 270 is performed.
To return to the main control routine.

Steps 110 and 140
Is determined, the rotational speed Ne of the traveling engine 1 is 0.
When it is determined that is, the routine proceeds to step 180, where it is first determined whether or not the flag B indicating that the power supply to the electric motor 7 has been started is set to "1". If “1” is not set in the flag B, the process proceeds to step 190, and it is determined whether or not “1” is set in the flag A indicating the operation of the timer T. In this determination, if "1" is not set in the flag A, the process proceeds to step 200 to start the timer T, and in step 210, the flag A indicating the operation of the timer T is set to "1". Therefore, from the next time, steps 200 and 210 are bypassed by the determination in step 190, and in step 220, it is determined whether or not the timer T has elapsed a predetermined time α. As a result, it is possible to detect that the traveling engine 1 is in the stopped state during the predetermined time α.

If it is determined in step 220 that the stopped state of the traveling engine 1 has continued for a predetermined time α, the process proceeds to step 230 to apply the voltage Vm to the electric motor 7. Then, in step 240, "1" is set to the flag B indicating the operation of the electric motor 7. Then, the routine proceeds to step 250, where the compressor discharge capacity C
It is determined whether or not c has reached the maximum discharge capacity Cmm by the electric motor 7.
At 0, the compressor discharge capacity Cc is increased by + β. As a result, the compressor discharge capacity Cc gradually increases up to the maximum discharge capacity Cmm of the electric motor, so that the driving load of the air conditioning compressor 5 gradually increases. Therefore, the current Im flowing to the electric motor 7 gradually increases,
This can prevent the occurrence of a sudden inrush current.

The above control will be described with reference to a timing chart shown in FIG.
Decreases from the normal running rotation speed to the idling rotation speed Na (t1 to t2), at time t2, the compressor discharge capacity Cc is set to “0”, and the compressor discharge capacity Cc decreases toward 0 (destroke). (T2 to t3). Then, the rotation speed Ne of the traveling engine 1 becomes “0” (t4), and a predetermined time elapses (t4 to t4).
5) After that, the voltage Vm is applied to the electric motor 7 (t
5). Then, thereafter, from time t6, the compressor discharge capacity Cc is changed to the maximum discharge capacity Cmm (t
By increasing the current Im gradually to 7), a sudden increase in the current Im supplied to the electric motor 7 is prevented.

The hybrid compressor control according to the second embodiment shown in FIGS. 4 and 5 shows a case where the air-conditioning compressor 5 has a fixed displacement without the variable displacement mechanism 8. Hereinafter, this embodiment will be described. However, the same portions as those in the above-described embodiment or portions having similar effects are denoted by the same reference numerals, and description thereof is omitted.

In the second embodiment, when the rotational speed Ne of the traveling engine 1 matches the idling rotational speed Na, the electromagnetic clutch (Mgcl) 6 is turned off to stop the operation of the air conditioning compressor 5. , The rotational speed N of the traveling engine 1 as described above in step 130.
e is set to “0”. If it is determined in steps 110 and 140 that the running engine 1 has reached the idling rotational speed Na or higher, step 155 is executed.
And the electromagnetic clutch 6 is engaged. Furthermore, after a lapse of a predetermined time α after the driving engine 1 is stopped, the voltage Vm applied to the electric motor 7 is gradually increased to the rated voltage Vmm of the electric motor 7 by the determination in steps 265 and 255. Therefore, since the current supplied to the electric motor 7 gradually increases, it is possible to prevent the inrush current to the electric motor 7 from exceeding the rated value.

The above control will be described with reference to a timing chart shown in FIG.
Is reduced from the normal running rotation speed to the idling rotation speed Na (t1 to t2), the electromagnetic clutch 6 is turned off at the time t2, so that the compressor drive torque τ
c becomes 0. Then, the rotation speed N of the traveling engine 1
e becomes “0” (t4), and a predetermined time elapses (t4 to t4).
5) After that, the voltage Vm is applied to the electric motor 7, and this voltage Vm is gradually increased (t5 to t7), thereby preventing a rapid increase in the current Im supplied to the electric motor 7.

[0023]

As described above, according to the present invention, when the electric motor is driven after the traveling engine is stopped, the compressor capacity is gradually increased from 0 (destroke), or the compressor capacity is increased. By gradually increasing the voltage and gradually increasing the current value flowing to the electric motor, it was possible to prevent a large current from flowing suddenly to the electric motor, thereby preventing damage to the electric motor and ensuring a stable compressor. You can get the operation.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating hybrid compressor control according to the first embodiment of the present invention.

FIG. 3 is a timing chart illustrating hybrid compressor control according to the first embodiment of the present invention.

FIG. 4 is a flowchart illustrating hybrid compressor control according to a second embodiment of the present invention.

FIG. 5 is a timing chart showing hybrid compressor control according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Running engine 5 Air-conditioning compressor 6 Electromagnetic clutch 7 Electric motor 8 Variable capacity mechanism 20 Control unit

Claims (3)

[Claims] 1. A hybrid compressor driven by the electric motor when the driving engine is stopped, wherein at least a driving engine and an electric motor are selected as drive sources, and an overload current at the time of starting the electric motor is prevented. A hybrid compressor control device comprising overload current prevention means. 2. The hybrid compressor according to claim 1, further comprising a variable displacement mechanism, wherein the overload current preventing means gradually increases a discharge capacity of the compressor from zero or a minimum capacity when the electric motor is started. The hybrid compressor control device according to claim 1, wherein 3. The hybrid compressor according to claim 1, wherein the hybrid compressor is a fixed displacement compressor, and wherein the overload current prevention means gradually increases a supply voltage to the electric motor from zero when the electric motor is started. The hybrid compressor control device according to claim 1.