JP3344034B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner provided with an electric compressor driven by a DC power supply.

[0002]

2. Description of the Related Art In an air conditioner using an electric compressor, an electric compressor driving device for driving an electric compressor for air conditioning supplies a large current to the electric compressor. Is provided in the power supply unit. This will be described with reference to FIG.

[0003] A battery 3 is connected to the electric compressor driving device 1. However, a floating inductance 8 formed by wiring or the like exists between them.
The electric compressor driving device 1 is connected to the electric compressor 2.

[0004] The output portion to the electric compressor 2 of the electric compressor driving device 1 has a structure shown in FIG. 3 (b). The generation of the recovery current is as follows.

When the upper output transistor 4 and the lower output transistor 5 are turned on, the current a is supplied to the electric compressor 2.
Is shed. Next, when the lower output transistor 5 is turned off, the current b flows through the flywheel diode 6 due to the inductance of the motor coil of the electric compressor 2. Thereby, the flywheel diode 6
, A recovery current c of the flywheel diode 6 flows when the lower output transistor 5 is turned on next time.

[0006] Since the flow in the recovery current c is the stray inductance 8, the stray inductance 8 when recovery current c is OFF, Sa as shown in FIG. 3 (b) to the power supply input voltage vp to the electric compressor driving device 1
Over di voltage is generated.

This surge voltage causes destruction of the upper output transistor 4, the lower output transistor 5, and the like. Therefore, normally, as shown in FIG. 3C , a recovery current countermeasure capacitor 7 which serves as a supply source of the recovery current c of the flywheel diode 6 and prevents it from flowing to the stray inductance 8 is connected to the power supply input to the electric compressor driving device 1. Section.

[0008]

In the circuit configured as described above, a resonance current flows through the power supply line of the electric compressor driving device 1 as follows, causing electromagnetic wave interference and the occurrence of electromagnetic interference. Problems such as heat generation, generation of a voltage pulse in the power supply line, and inaccurate current detection of the power supply line occur.

FIG. 4 As shown in the illustration of the resonance current of the electric compressor air conditioner, a circuit inductance 9 such as a transformer of a current detection device exists in the power supply line in addition to the stray inductance 8 because of the necessity on the circuit. I have.

[0010] the electric compressor driving device 1 the current i _m shown in FIG. 4 flows, the rise of the current, at the falling, the resonant current i _c flows by the recovery current measures capacitor 7 and the circuit inductance 9 and stray inductance 8 . Therefore a voltage pulse occurs in the voltage v _p of the power supply line of the electric compressor driving device 1, the current i _LC power supply line, the rise of the current, at the falling, so that the components of the resonant current i _c flows.

Therefore, the present invention is driven by a DC power supply which eliminates problems such as generation of electromagnetic interference due to resonance current, heat generation of a capacitor provided in a power supply line, voltage pulse of the power supply line, and deterioration of current detection accuracy of the power supply line. The purpose is to provide an electric compressor air conditioner.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides, as first means, a DC power supply, and an electric compressor driving apparatus which is supplied with electric power from the DC power supply and drives an electric compressor for air conditioning. In an air conditioner having a capacitor for supplying an instantaneous current to the electric compressor driving device and an inductance component in a current flow path of the electric compressor driving device, a diode is connected in parallel with the inductance component.

In order to solve the above-mentioned problems, the present invention provides, as second means, a DC power source, an electric compressor driving device which is supplied with power from the DC power source, and drives an air-conditioning electric compressor, and an electric compressor driving device. An air conditioner equipped with a capacitor that supplies an instantaneous current to the current and a current detection device that detects a current by an inductance component in a current flow path of the electric compressor drive device, and a diode is provided in one direction in parallel with the current detection device. Connect.

In order to solve the above-mentioned problems, the present invention provides, as third means, a DC power supply, an electric compressor driving device which is supplied with electric power from the DC power supply and drives an electric compressor for air conditioning, and an electric compressor driving device. An air conditioner that includes a capacitor that supplies an instantaneous current to the motor and a current detection device that detects a current by an inductance component in a path through which the current of the electric compressor driving device flows. Connect.

[0015]

According to the first means of the present invention, a DC power supply, an electric compressor driving device which is supplied with electric power from the DC power supply and drives an electric compressor for air conditioning, and an instantaneous electric current are supplied to the electric compressor driving device. In an air conditioner provided with a capacitor and an inductance component in a current flow path of the electric compressor drive device, a diode is connected in parallel with the inductance component.

As shown in FIG. 5, when a diode is connected in parallel with the circuit inductance 9 in the direction opposite to the path of the DC current of the electric compressor driving device, this diode is referred to as a reverse resonance current countermeasure diode 10.

[0017] the electric compressor driving device 1 the current i _m shown in FIG. 5 flows, the rise of the current, at the falling, the recovery current measures capacitor 7 and the circuit inductance 9 and stray inductance 8,
The resonance current _ic shown in FIG. 4 is about to flow. However, the resonance energy is absorbed by the reverse resonant current measures diode 10, current flows i _D shown in FIG. 5 in the reverse resonant current measures diode 10. Accordingly, the resonance current _ic shown in FIG. 5 is smaller than the resonance current _ic shown in FIG. Then, the voltage pulse generated in the voltage v _p is also reduced. Meanwhile, current of the power supply line i _LC current i _m as shown in FIG. 5
And the current i _D.

Therefore, the resonance current _ic is reduced, thereby reducing the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line.

As a second means of the present invention, a DC power supply, an electric compressor driving device which is supplied with electric power from the DC power supply and drives an electric compressor for air conditioning, and supplies an instantaneous current to the electric compressor driving device In an air conditioner provided with a capacitor and a current detection device for detecting a current by an inductance component in a current flow path of the electric compressor drive device, a diode is connected in one direction in parallel with the current detection device.

As shown in FIG. 6, when a diode is connected in parallel with the circuit inductance 9 in the same direction as the path of the DC current of the electric compressor driving device, this diode is referred to as a forward resonance current countermeasure diode 11.

[0021] the electric compressor driving device 1 the current i _m shown in FIG. 6 flows, the rising of the current, at the falling, the recovery current measures capacitor 7 and the circuit inductance 9 and stray inductance 8,
The resonance current _ic shown in FIG. 4 is about to flow. However, the absorption resonance energy in the forward resonance current measures diode 11, current flows i _D shown in FIG. 6 in the forward resonance current measures diode 11. Thus, the resonance current _ic shown in FIG. 6 is smaller than the resonance current _ic shown in FIG. Then, the voltage pulse generated in the voltage v _p is also reduced. Meanwhile, current of the power supply line i _LC current i _m as shown in FIG. 6
And the current i _D.

Therefore, the resonance current _ic is reduced, thereby reducing the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line. Also,
To protect the electric compressor driving device 1 or the like it is necessary to monitor the maximum value of the current i _m to (A point in FIG. 6) by the current detection device. Current detected by the current detector is i _LC, the maximum value is equal to the maximum value of the current i _m the resonance current i _c does not flow. Therefore, the current detection of the power supply line becomes extremely accurate.

As a third means of the present invention, a DC power supply, an electric compressor drive device supplied with electric power from the DC power supply to drive an electric compressor for air conditioning, and an instantaneous current supply to the electric compressor drive device In an air conditioner including a capacitor and a current detection device that detects a current by an inductance component in a path through which a current of the electric compressor driving device flows, a diode is bidirectionally connected in parallel with the current detection device.

As shown in FIG. 7, both a reverse resonance current countermeasure diode 10 and a forward resonance current countermeasure diode 11 are connected in parallel with the circuit inductance 9.

[0025] the electric compressor driving device 1 the current i _m shown in FIG. 7 flows, the rise of the current, at the falling, the recovery current measures capacitor 7 and the circuit inductance 9 and stray inductance 8,
The resonance current _ic shown in FIG. 4 is about to flow. However, in the rising is absorbed resonant energy in the forward resonance current measures diode 11, current flows i _DF shown in FIG. 7 in the forward resonance current measures diode 11. Also, at the fall, the resonance energy is absorbed by the reverse resonance current countermeasure diode 10, and the current _iDR shown in FIG.

Therefore, the resonance current _ic shown in FIG. 7 is smaller than the resonance current _ic shown in FIG. Then, the voltage pulse generated in the voltage v _p is also reduced. On the other hand, the power supply line current i _{L C} is a current i _m and current i _DF and i _DR as shown in FIG. 7
And the sum of

Therefore, the resonance current i_cIs reduced
Electromagnetic interference, capacitors installed on power lines
Heat generation and voltage pulses on the power supply line are reduced. Also,
To protect the electric compressor drive 1 etc.
Flow i_mThe maximum value (point A in Fig. 7) is monitored by the current detection device
It is necessary to keep. The current detected by the current detector is
i_LCAnd its maximum value is the resonance current i_cDoes not flow
And the current i_mIs equal to the maximum of Therefore, the power line
Flow detection becomes extremely accurate. Further, in this case i _LCNima
Since the negative current does not flow, the rectifier circuit
It becomes unnecessary and simple.

[0028]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 1 shows a circuit diagram and a configuration diagram of an electric compressor air conditioner according to a first embodiment of the present invention.

The difference from the diagram for explaining the resonance current of the electric compressor air conditioner shown in FIG. 4 is that the reverse resonance current countermeasure diode 1 is connected in parallel to the wiring 14 corresponding to the circuit inductance 9.
0 is connected.

In an electric compressor driven by a DC power supply, a large current of 20 A flows when the DC power supply is as low as 100 V and the output is 2 kW in an electric vehicle or the like. Also, because of DC, fuse 1
3. The energizing relay 16 and the like become special products and have a large breaking capacity, so they are quite large components. Therefore, it cannot be mounted on a printed circuit board. Therefore, the wiring 14 is required for connection with the printed circuit board, and this wiring 14 contributes to the circuit inductance 9.

Accordingly, by connecting the reverse resonance current countermeasure diode 10 in parallel to the wiring 14, the recovery current countermeasure capacitor 7 and the wiring 14 can be connected at the rise and fall of the current of the electric compressor driving device 1.
The energy of the resonance current due to the (circuit inductance 9) and the stray inductance 8 is absorbed by the reverse-direction resonance current suppression diode 10. Therefore, the resonance current is reduced, and the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line are reduced, and the effect of the first means can be obtained.

In this case, the fuse 13 and the energizing relay 16
Since the diode is connected in the opposite direction to the direct current flowing through the circuit, the operation of the electric circuit is not affected.

FIG. 2A shows a circuit diagram of an electric compressor air conditioner according to a second embodiment of the present invention.

The difference from the illustration of the resonance current of the electric compressor air conditioner of FIG. 4 is that a forward resonance current countermeasure diode 11 is connected in parallel to the primary side of a current detection transformer 17 corresponding to the circuit inductance 9. It is. Here, a current waveform is transmitted from the primary side of the current detection transformer 17 to the secondary side, and a negative current is not detected by the rectifier diode 18 on the secondary side.

By connecting the forward resonance current countermeasure diode 11 in parallel with the primary side of the current detection transformer 17, the recovery current countermeasure capacitor 7 and the current detection transformer 17 are used when the current of the electric compressor drive device 1 rises and falls. The energy of the resonance current due to the primary side (circuit inductance 9) and the stray inductance 8 is absorbed by the forward resonance current suppression diode 11. Accordingly, the resonance current is reduced, and the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line are reduced, and the effect of the second means can be obtained.

In this case, the voltage drop due to the DC current flowing through the primary side of the current detecting transformer 17 is sufficiently smaller than the forward voltage of the forward-resonant-current countermeasure diode 11, so that the operation of the electric circuit is not affected.

The maximum value of the current flowing through the electric compressor driving device is equal to the maximum value of the current flowing through the primary side of the current detection transformer 17. Further, the negative current is not detected by the rectifier diode 18 on the secondary side. Therefore, the current detection of the power supply line becomes extremely accurate.

FIG. 2B shows a circuit diagram of an electric compressor air conditioner according to a third embodiment of the present invention.

The difference from the illustration of the resonance current of the electric compressor air conditioner shown in FIG. 4 is that the diode 11 and the reverse resonance current countermeasure are provided in parallel with the primary side of the current detection transformer 17 corresponding to the circuit inductance 9. The point is that both of the diodes 10 are connected. Here, the current waveform is transmitted from the primary side of the current detection transformer 17 to the secondary side.

By connecting both the forward resonance current countermeasure diode 11 and the reverse resonance current countermeasure diode 10 to the primary side of the current detection transformer 17 in parallel, recovery at the rise and fall of the current of the electric compressor driving device 1 is achieved. The energy of the resonance current due to the current countermeasure capacitor 7, the primary side (circuit inductance 9) of the current detection transformer 17 and the stray inductance 8 is
At the time of rising, the forward resonance current suppression diode 11 is used. At the time of falling, the reverse resonance current suppression diode 10 is used.
Absorbed by Therefore, the resonance current is reduced, and the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line are reduced, and the effect of the third means can be obtained.

In this case, the voltage drop due to the DC current flowing through the primary side of the current detection transformer 17 is sufficiently smaller than the forward voltage of the forward-direction resonance current countermeasure diode 11, so that the operation of the electric circuit is not affected.

The maximum value of the current flowing to the electric compressor driving device is equal to the maximum value of the current flowing to the primary side of the current detection transformer 17. Therefore, the current detection of the power supply line becomes extremely accurate.

Further, in this case, since no negative current flows, the rectifier diode 18 is not required on the secondary side of the current detecting transformer 17.

In the second embodiment, the diode 11 for preventing forward resonance current is used. However, the diode 10 for preventing reverse resonance current is used to convert the primary current of the current detecting transformer 17 including the resonance current. It may be detected and used for a protection function or the like.

In addition, the present invention is not limited to the above, and various applications are possible as long as the gist of the present invention is satisfied.

[0047]

According to the first means of the present invention, the resonance current _ic is reduced, so that the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line are reduced.

According to the second means of the present invention, the resonance current i
_c is reduced, so that the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line are reduced. Further, the maximum value of the current detected by the current detection device is equal to the maximum value of the current flowing through the electric compressor driving device 1 because no resonance current flows. Therefore, the current detection of the power supply line becomes extremely accurate.

According to the third means of the present invention, the resonance current i
_c is reduced, so that the occurrence of electromagnetic interference, the heat generated by the capacitor provided on the power supply line, and the voltage pulse on the power supply line are reduced. Further, the maximum value of the current detected by the current detection device is equal to the maximum value of the current flowing through the electric compressor driving device 1 because no resonance current flows. Therefore, the current detection of the power supply line becomes extremely accurate. Further, since a negative current does not flow through the current detection device, the current detection device does not require a rectifying circuit or the like, which is simplified.

[Brief description of the drawings]

FIG. 1A is a circuit diagram of an air conditioner according to a first embodiment of the present invention. FIG. 1B is a configuration diagram of the main part. FIG.

FIG. 2A is a circuit diagram of an air conditioner according to a second embodiment of the present invention; FIG. 2B is a circuit diagram of an air conditioner according to a third embodiment of the present invention;

FIG. 3 (a) is an explanatory diagram of a recovery current measure of the air conditioner, FIG. 3 (b) is an explanatory diagram thereof, and FIG.

FIG. 4A is a diagram illustrating a resonance current of the air conditioner, and FIG. 4B is a diagram illustrating the same.

FIG. 5A is an explanatory view of a means for solving the problem of the present invention, and FIG.

FIG. 6A is an explanatory view of a means for solving the problem of the present invention, and FIG.

FIG. 7A is an explanatory view of a means for solving the problem of the present invention, and FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric compressor drive device 2 Electric compressor 3 Battery 4 Upper output transistor 5 Lower output transistor 6 Flywheel diode 7 Recovery current countermeasure capacitor 8 Floating inductance 9 Circuit inductance 10 Reverse resonance current countermeasure diode 11 Forward resonance current countermeasure diode 12 Missing 13 Fuse 14 Wiring 15 Circuit printed circuit board 16 Current relay 17 Current detection transformer 18 Rectifier diode

────────────────────────────────────────────────── ─── Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02P 5/408-5/412 H02P 7/628-7/632 H02P 21/00 H02M 7/42-7 / 98 F24F 11/00-11/02 F25B 43/00-49/04

Claims (2)

(57) [Claims] An electric compressor drive for converting an electric power from a DC power supply into an alternating current to drive an electric compressor, and a capacitor connected between plus and minus of a power supply line connecting the DC power supply and the electric compressor drive. And a coil inserted in the middle of a power supply line connecting the DC power supply and the electric compressor driving device, a current detection device that detects a current value flowing through the coil by a magnetic flux generated from the coil, and in parallel with the coil. And a diode to be connected, wherein the coil is
Power source line, and insert the diode
The node is an air conditioner connected to the electric compressor drive device side. 2. The air conditioner according to claim 1, further comprising an additional diode connected in parallel with said coil and in a direction opposite to said diode.