JP7658290B2 - Electric Compressor - Google Patents

Description

The present invention relates to an electric compressor.

The electric compressor includes a compression section, an electric motor, and an inverter device. The compression section compresses the fluid. The electric motor drives the compression section. The inverter device has a circuit board. The circuit board drives the electric motor. The electric compressor also includes a connector. The connector is electrically connected to a power source. Furthermore, the inverter device includes an inverter circuit. The inverter circuit converts DC power input from the power source via the connector into AC power.

For example, as in Patent Document 1, the inverter device includes a filter circuit. The filter circuit is provided on the connector side of the inverter circuit and reduces noise. Specifically, the filter circuit includes a coil, a first capacitor, and a second capacitor. The first capacitor is provided on the connector side of the coil. The second capacitor is provided on the inverter circuit side of the coil. The coil, the first capacitor, and the second capacitor are mounted on a circuit board. The circuit board includes a conductive pattern. The conductive pattern electrically connects the first capacitor and the second capacitor. The conductive pattern is connected to ground.

The noise generated from the inverter circuit flows to ground via the coil, the first capacitor, and the conductive pattern, or flows to ground via the second capacitor and the conductive pattern. This prevents the noise generated from the inverter circuit from flowing to the connector. As a result, the noise generated from the inverter circuit is prevented from leaking to the outside via the connector.

JP 2019-187228 A

However, in such an electric compressor, there is a risk that noise flowing from the inverter circuit through the second capacitor to the conductive pattern may flow via the first capacitor to the connector. If noise generated from the inverter circuit flows to the connector, there is a risk that the noise generated from the inverter circuit may leak out through the connector to the outside. Therefore, in such an electric compressor, it is desirable to prevent noise generated from the inverter circuit from leaking out through the connector to the outside.

The electric compressor that solves the above problem includes a compression section that compresses a fluid, an electric motor that drives the compression section, an inverter device having a circuit board that drives the electric motor, and a connector that is electrically connected to a power source. The inverter device includes an inverter circuit that converts DC power input from the power source through the connector into AC power, and a filter circuit that is provided on the connector side of the inverter circuit and reduces noise. The filter circuit includes a coil, a first capacitor that is provided on the connector side of the coil, and a second capacitor that is provided on the inverter circuit side of the coil. The coil, the first capacitor, and the second capacitor are mounted on the circuit board. The circuit board has a conductive pattern that electrically connects the first capacitor and the second capacitor, and the conductive pattern is connected to ground. The circuit board has an insulating portion that makes the impedance between the first capacitor and the second capacitor in the conductive pattern larger than the impedance between the second capacitor in the conductive pattern and the ground.

According to this, the insulating portion makes the impedance between the first capacitor and the second capacitor in the conductive pattern larger than the impedance between the second capacitor and ground in the conductive pattern. Therefore, noise flowing from the inverter circuit via the second capacitor to the conductive pattern is less likely to flow via the first capacitor to the connector. And noise flowing from the inverter circuit via the second capacitor to the conductive pattern is more likely to flow to ground. As a result, it is possible to suppress noise generated from the inverter circuit from leaking to the outside via the connector.

In the above electric compressor, a slit is formed in the conductive pattern, extending from between the first capacitor and the second capacitor toward the ground, and the slit may constitute the insulating portion.

According to this, an insulating section can be formed simply by forming a slit in the conductive pattern that extends from between the first capacitor and the second capacitor toward the ground. Therefore, there is no need to add, for example, a new coil, capacitor, etc. to the circuit board to prevent noise generated by the inverter circuit from leaking out to the outside via the connector. As a result, it is possible to avoid the formation of a new noise path on the circuit board by adding a new coil, capacitor, etc. to the circuit board.

This invention makes it possible to prevent noise generated by the inverter circuit from leaking to the outside through the connector.

1 is a cross-sectional view of an electric compressor according to an embodiment. FIG. 2 is a circuit diagram showing an electrical configuration of the electric compressor. FIG.

An embodiment of an electric compressor will now be described with reference to Figures 1 to 3. The electric compressor of the present embodiment is used, for example, in a vehicle air conditioner.
(Overall configuration of vehicle Ve)
As shown in FIG. 1, the vehicle Ve includes an electric storage device B and a vehicle air conditioner 100. The electric storage device B is a power source that supplies power to devices mounted on the vehicle Ve. The electric storage device B is a DC power source. The electric storage device B is, for example, a secondary battery or a capacitor. The vehicle air conditioner 100 includes an external refrigerant circuit 110, an air conditioning ECU 120, and an electric compressor 10. The external refrigerant circuit 110 supplies a refrigerant as a fluid to the electric compressor 10. The external refrigerant circuit 110 includes, for example, a heat exchanger and an expansion valve. The external refrigerant circuit 110 performs heat exchange between the outside and the refrigerant to perform heating and cooling of the interior of the vehicle Ve. The air conditioning ECU 120 is configured to be able to grasp the vehicle interior temperature, the set temperature of the car air conditioner, and the like. The air conditioning ECU 120 transmits various commands, such as an ON/OFF command, to the electric compressor 10 based on parameters such as the vehicle interior temperature and the set temperature of the car air conditioner.

(Overall configuration of electric compressor 10)
The electric compressor 10 includes a housing 20, a rotating shaft 30, a compression unit 31, an electric motor 32, a connector 36, and an inverter device 40. The housing 20 is made of metal. For example, the housing 20 is made of aluminum. The material of the housing 20 may be any metal that has thermal conductivity. The housing 20 is grounded to a body (not shown) of the vehicle Ve.

The housing 20 has a suction housing 21, a discharge housing 22, and a cover member 23. The suction housing 21 has a plate-shaped end wall 21a, a cylindrical peripheral wall 21b, and a suction port 21c. The peripheral wall 21b stands up from the outer periphery of the end wall 21a toward the discharge housing 22. The suction port 21c is connected to the external refrigerant circuit 110. The suction port 21c is provided in the peripheral wall 21b.

The discharge housing 22 is attached to the suction housing 21 while blocking the opening of the suction housing 21. As a result, the suction housing 21 and the discharge housing 22 form a motor accommodating chamber S1 within the housing 20. The discharge housing 22 has a discharge port 22a. The discharge port 22a is connected to the external refrigerant circuit 110.

The cover member 23 has a plate-shaped end wall 23a and a cylindrical peripheral wall 23b. The cover member 23 is attached to the end wall 21a of the suction housing 21 with the open end of the peripheral wall 23b abutting against the end wall 21a. The opening of the peripheral wall 23b of the cover member 23 is blocked by the end wall 21a. As a result, the end wall 21a and the cover member 23 form the inverter accommodating chamber S2. Therefore, the housing 20 has the inverter accommodating chamber S2. The end wall 21a separates the motor accommodating chamber S1 from the inverter accommodating chamber S2.

The rotating shaft 30 is configured to be rotatable relative to the housing 20. The rotating shaft 30 is rotatably supported by the housing 20. The rotating shaft 30 is accommodated in the motor accommodation chamber S1 with the axial direction of the rotating shaft 30 coinciding with the axial direction of the peripheral wall 21b.

(Configuration of Compression Unit 31)
The compression section 31 is accommodated in the suction housing 21. The compression section 31 is, for example, a scroll type including a fixed scroll (not shown) fixed in the suction housing 21 and a movable scroll (not shown) arranged opposite the fixed scroll. The compression section 31 is arranged in the motor accommodating chamber S1 at a position closer to the discharge port 22a than the suction port 21c. The compression section 31 is connected to the rotating shaft 30. The compression section 31 is driven by the rotation of the rotating shaft 30 to compress the refrigerant.

(Configuration of electric motor 32)
The electric motor 32 is accommodated in the motor accommodating chamber S1. The electric motor 32 is disposed between the compression section 31 and the end wall 21a in the motor accommodating chamber S1. The electric motor 32 has, for example, a cylindrical rotor 33, a stator 34, and three-phase coils 35u, 35v, and 35w. The rotor 33 is fixed to the rotating shaft 30. This allows the rotating shaft 30 to rotate integrally with the rotor 33. The stator 34 is fixed to the peripheral wall 21b of the housing 20. The rotor 33 and the stator 34 face each other in the radial direction of the rotating shaft 30.

The three-phase coils 35u, 35v, and 35w are each wound around the stator 34. The three-phase coils 35u, 35v, and 35w are, for example, Y-connected. Note that the connection of the three-phase coils 35u, 35v, and 35w is not limited to Y-connection and may be any connection. The connection of the three-phase coils 35u, 35v, and 35w may be, for example, delta-connected.

The rotor 33 rotates when the three-phase coils 35u, 35v, and 35w are energized in a predetermined pattern. The rotor 33 rotates, and the rotating shaft 30 rotates. This drives the compression section 31. The electric motor 32 drives the compression section 31. The refrigerant flowing through the external refrigerant circuit 110 is then sucked into the housing 20 from the suction port 21c. The compression section 31 compresses the refrigerant sucked into the housing 20. The compressed refrigerant is discharged from the discharge port 22a to the external refrigerant circuit 110.

(Regarding connector 36)
The connector 36 is a terminal for supplying electric power from the power storage device B mounted on the vehicle Ve to the inverter device 40. The connector 36 is electrically connected to the power storage device B. The connector 36 is provided on the cover member 23.

(Overall configuration of inverter device 40)
The inverter device 40 is accommodated in the inverter accommodating chamber S2. Thus, the housing 20 accommodates the inverter device 40. The inverter device 40 is electrically connected to the power storage device B via a connector 36.

The inverter device 40 has a circuit board 41. The circuit board 41 drives the electric motor 32. The circuit board 41 is accommodated in the inverter accommodation chamber S2. The circuit board 41 is disposed facing the end wall 21a at a predetermined distance in the axial direction of the rotating shaft 30. The circuit board 41 is accommodated in the inverter accommodation chamber S2 with the thickness direction of the circuit board 41 coinciding with the axial direction of the rotating shaft 30.

As shown in FIG. 2 , the inverter device 40 includes an inverter circuit 42 , a control unit 43 , and a filter circuit 44 .
(Regarding the inverter circuit 42)
The inverter circuit 42 includes a positive bus bar Lp, a negative bus bar Ln, six switching elements Q1 to Q6, and six diodes D1 to D6. IGBTs are used as the switching elements Q1 to Q6. Between the positive bus bar Lp and the negative bus bar Ln, a switching element Q1 constituting a u-phase upper arm and a switching element Q2 constituting a u-phase lower arm are connected in series. Between the positive bus bar Lp and the negative bus bar Ln, a switching element Q3 constituting a v-phase upper arm and a switching element Q4 constituting a v-phase lower arm are connected in series. Between the positive bus bar Lp and the negative bus bar Ln, a switching element Q5 constituting a w-phase upper arm and a switching element Q6 constituting a w-phase lower arm are connected in series. Diodes D1 to D6 are connected in inverse parallel to the switching elements Q1 to Q6.

The u-phase coil 35u of the electric motor 32 is connected between the switching element Q1 and the switching element Q2. The v-phase coil 35v of the electric motor 32 is connected between the switching element Q3 and the switching element Q4. The w-phase coil 35w of the electric motor 32 is connected between the switching element Q5 and the switching element Q6. The inverter circuit 42, which has the switching elements Q1 to Q6 constituting the upper and lower arms, is configured to convert DC voltage to AC voltage and output it to the electric motor 32 in accordance with the switching operation of the switching elements Q1 to Q6. Therefore, the inverter circuit 42 converts the DC power input from the storage device B via the connector 36 into AC power.

(Regarding the control unit 43)
The control unit 43 controls the switching operation of each of the switching elements Q1 to Q6. The control unit 43 can be realized, for example, by one or more dedicated hardware circuits and/or one or more processors (control circuits) that operate according to a computer program (software). The processor includes a CPU and memory such as RAM and ROM, and the memory stores, for example, program codes or instructions configured to cause the processor to execute various processes. Memory, i.e., computer-readable medium, includes any available medium that can be accessed by a general-purpose or dedicated computer.

The control unit 43 periodically turns each of the switching elements Q1 to Q6 ON/OFF based on a command from the air conditioning ECU 120. In detail, the control unit 43 PWM controls each of the switching elements Q1 to Q6 based on a command from the air conditioning ECU 120. The control unit 43 generates a control signal using the carrier signal and the command voltage value signal. Then, the control unit 43 converts DC power to AC power by controlling ON/OFF of each of the switching elements Q1 to Q6 using the generated control signal.

(Regarding the filter circuit 44)
The filter circuit 44 is provided on the connector 36 side with respect to the inverter circuit 42. The filter circuit 44 is provided between the connector 36 and the inverter circuit 42. The filter circuit 44 reduces noise contained in the DC power input from the connector 36 to the inverter circuit 42. The filter circuit 44 also reduces noise generated from the inverter circuit 42 and flowing toward the connector 36. Note that the noise generated from the inverter circuit 42 is, for example, noise generated in conjunction with the switching operations of the switching elements Q1 to Q6.

The filter circuit 44 is connected to the positive bus Lp and the negative bus Ln. Therefore, the filter circuit 44 is provided on the input side of the inverter circuit 42. The filter circuit 44 has a smoothing capacitor 45, a coil 46, a first capacitor 47, and a second capacitor 48.

The smoothing capacitor 45 is an X capacitor connected in parallel to the inverter circuit 42. Specifically, the smoothing capacitor 45 is connected to the positive bus bar Lp and the negative bus bar Ln.

The coil 46 is, for example, a common mode choke coil. The coil 46 is provided on the input side of the inverter circuit 42. The coil 46 has a leakage inductance L. The leakage inductance L functions as a choke coil for normal mode noise. Therefore, the leakage inductance L, together with the smoothing capacitor 45, constitutes a low-pass filter circuit that removes normal mode noise. As a result, the coil 46 reduces the noise contained in the DC power. Therefore, the filter circuit 44 removes common mode noise and normal mode noise.

The filter circuit 44 has two first capacitors 47. The two first capacitors 47 are connected in series. The space between the two first capacitors 47 is grounded to the body of the vehicle Ve via the housing 20. The two first capacitors 47 are provided on the connector 36 side with respect to the coil 46. The two first capacitors 47 are connected in parallel to the connector 36. The two first capacitors 47 are connected in parallel to the coil 46. The two first capacitors 47 are located between the connector 36 and the coil 46.

The filter circuit 44 has two second capacitors 48. The two second capacitors 48 are connected in series. The space between the two second capacitors 48 is grounded to the body of the vehicle Ve via the housing 20. The two second capacitors 48 are provided on the inverter circuit 42 side with respect to the coil 46. The two second capacitors 48 are connected in parallel with the coil 46. The two second capacitors 48 are connected in parallel with the smoothing capacitor 45. The two second capacitors 48 are located between the coil 46 and the smoothing capacitor 45.

(Details of the configuration of the circuit board 41)
As shown in Fig. 3, the coil 46, the first capacitor 47, and the second capacitor 48 are mounted on the circuit board 41. For convenience of explanation, only one each of the first capacitor 47 and the second capacitor 48 is shown in Fig. 3. In addition, the smoothing capacitor 45 is also mounted on the circuit board 41, but is not shown in Fig. 3 for convenience of explanation.

The circuit board 41 has a first conductive pattern 51, a second conductive pattern 52, and a third conductive pattern 53. The circuit board 41 also has an insulating layer 54. The insulating layer 54 is formed, for example, from a plate-shaped glass epoxy resin. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are formed from a sheet-shaped copper foil. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are patterned into a predetermined shape. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are provided on the surface of the insulating layer 54. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are provided on the surface of the insulating layer 54 while being spaced apart from each other to an extent that insulation between them can be ensured.

The first conductive pattern 51 is electrically connected to the inverter circuit 42. The first conductive pattern 51 has a first edge 51a facing the second conductive pattern 52. The first conductive pattern 51 also has a second edge 51b facing the third conductive pattern 53. The second conductive pattern 52 is electrically connected to the connector 36. The second conductive pattern 52 has a third edge 52a facing the first edge 51a of the first conductive pattern 51. The second conductive pattern 52 also has a fourth edge 52b facing the third conductive pattern 53. The third conductive pattern 53 has a fifth edge 53a facing the second edge 51b of the first conductive pattern 51 and the fourth edge 52b of the second conductive pattern 52.

The first end of the coil 46 is connected to the first conductive pattern 51. The second end of the coil 46 is connected to the second conductive pattern 52. Thus, the coil 46 electrically connects the first conductive pattern 51 and the second conductive pattern 52. The coil 46 electrically connects the first conductive pattern 51 and the second conductive pattern 52 while straddling the gap between the first edge 51a of the first conductive pattern 51 and the third edge 52a of the second conductive pattern 52.

The third conductive pattern 53 is a conductive pattern that electrically connects the first capacitor 47 and the second capacitor 48. A first end of the first capacitor 47 is connected to the second conductive pattern 52. A second end of the first capacitor 47 is connected to the third conductive pattern 53. Thus, the first capacitor 47 electrically connects the second conductive pattern 52 and the third conductive pattern 53. The first capacitor 47 electrically connects the second conductive pattern 52 and the third conductive pattern 53 while straddling the gap between the fourth edge 52b of the second conductive pattern 52 and the fifth edge 53a of the third conductive pattern 53.

A first end of the second capacitor 48 is connected to the first conductive pattern 51. A second end of the second capacitor 48 is connected to the third conductive pattern 53. Thus, the second capacitor 48 electrically connects the first conductive pattern 51 and the third conductive pattern 53. The second capacitor 48 electrically connects the first conductive pattern 51 and the third conductive pattern 53 across the gap between the second edge 51b of the first conductive pattern 51 and the fifth edge 53a of the third conductive pattern 53.

A bolt 55 passes through the third conductive pattern 53. The bolt 55 is screwed into the housing 20 to fix the circuit board 41 to the housing 20. The bolt 55 is electrically connected to the housing 20. Therefore, the bolt 55 functions as a ground. The third conductive pattern 53 is electrically connected to the bolt 55. Therefore, the third conductive pattern 53 is connected to the ground. The third conductive pattern 53 is grounded to the body of the vehicle Ve via the bolt 55 and the housing 20.

(Regarding the slit 56)
A slit 56 is formed in the third conductive pattern 53. The slit 56 extends from a portion located between the first capacitor 47 and the second capacitor 48 on the fifth edge 53a of the third conductive pattern 53 toward the bolt 55. Specifically, the slit 56 has a first slit portion 56a and a second slit portion 56b. The first slit portion 56a extends from a portion located between the first capacitor 47 and the second capacitor 48 on the fifth edge 53a of the third conductive pattern 53 in a direction perpendicular to the fifth edge 53a. The second slit portion 56b extends from an end of the first slit portion 56a opposite to the fifth edge 53a toward the bolt 55 along the fifth edge 53a. Thus, the slit 56 extends from between the first capacitor 47 and the second capacitor 48 toward the ground.

(Regarding the current path of the third conductive pattern 53)
The cross-sectional area of the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 is smaller than when the slits 56 are not formed in the third conductive pattern 53. In addition, the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 is longer than when the slits 56 are not formed in the third conductive pattern 53. Therefore, the impedance between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 is larger than when the slits 56 are not formed in the third conductive pattern 53.

The slit 56 makes the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 longer than the current path between the second capacitor 48 and the bolt 55 in the third conductive pattern 53. In addition, the bolt 55 is present on the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53.

(Regarding the insulating portion 57)
The space inside the slit 56 functions as an insulating portion 57 that suppresses noise that has flowed from the inverter circuit 42 through the second capacitor 48 to the third conductive pattern 53 from flowing to the first capacitor 47 without passing through the bolt 55. Therefore, the insulating portion 57 makes the impedance between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 greater than the impedance between the second capacitor 48 in the third conductive pattern 53 and the bolt 55. Thus, the slit 56 constitutes the insulating portion 57. In this manner, the circuit board 41 has the insulating portion 57.

(Action)
Next, the operation of this embodiment will be described.
Noise generated from the inverter circuit 42 flows to ground via the coil 46, the first capacitor 47, and the third conductive pattern 53, for example, as shown by an arrow A1 in Fig. 3. Moreover, noise generated from the inverter circuit 42 flows to ground via the second capacitor 48 and the third conductive pattern 53, for example, as shown by an arrow A2 in Fig. 3. This prevents the noise generated from the inverter circuit 42 from flowing to the connector 36. As a result, the noise generated from the inverter circuit 42 is prevented from leaking to the outside via the connector 36.

The insulating portion 57 makes the impedance between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 greater than the impedance between the second capacitor 48 and the bolt 55 in the third conductive pattern 53. Therefore, noise flowing from the inverter circuit 42 through the second capacitor 48 to the third conductive pattern 53 is less likely to flow toward the connector 36 via the first capacitor 47. And, noise flowing from the inverter circuit 42 through the second capacitor 48 to the third conductive pattern 53 is more likely to flow to ground. As a result, noise generated from the inverter circuit 42 is prevented from leaking to the outside through the connector 36.

(effect)
The above embodiment can provide the following effects.
(1) The circuit board 41 has an insulating portion 57 that makes the impedance between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 greater than the impedance between the second capacitor 48 in the third conductive pattern 53 and ground. This makes it difficult for noise flowing from the inverter circuit 42 through the second capacitor 48 to the third conductive pattern 53 to flow toward the connector 36 via the first capacitor 47. Moreover, noise flowing from the inverter circuit 42 through the second capacitor 48 to the third conductive pattern 53 is more likely to flow to ground. As a result, it is possible to suppress noise generated from the inverter circuit 42 from leaking to the outside through the connector 36.

(2) The third conductive pattern 53 has a slit 56 extending from between the first capacitor 47 and the second capacitor 48 toward the ground. The slit 56 constitutes an insulating section 57. Thus, the insulating section 57 can be constituted by simply forming the slit 56 extending from between the first capacitor 47 and the second capacitor 48 toward the ground in the third conductive pattern 53. Therefore, in order to prevent noise generated from the inverter circuit 42 from leaking to the outside through the connector 36, it is not necessary to add, for example, a new coil, capacitor, etc. to the circuit board 41. As a result, it is possible to avoid the formation of a new noise path on the circuit board 41 by adding a new coil, capacitor, etc. to the circuit board 41.

(3) In order to prevent noise generated by the inverter circuit 42 from leaking to the outside through the connector 36, for example, there is no need to add new coils, capacitors, etc. to the circuit board 41. Therefore, it is possible to avoid an increase in size of the electric compressor 10, which would be caused by adding new coils, capacitors, etc. to the circuit board 41. In addition, since there is no need to change the arrangement space or layout of the circuit board 41 relative to the inverter accommodating chamber S2, the degree of freedom in the layout of the inverter accommodating chamber S2 can be improved.

(Example of change)
The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

In the above embodiment, MOSFETs may be used as the switching elements Q1 to Q6 instead of IGBTs. In this case, the diodes D1 to D6 are not required.
In the above embodiment, instead of the slits 56 , for example, a through hole penetrating the circuit board 41 may be formed to form the insulating portion 57 .

In the above-mentioned embodiment, the number of first capacitors 47 is not particularly limited.
In the above embodiment, the number of second capacitors 48 is not limited to a specific number.
In the above-mentioned embodiment, the coil 46 is not limited to a common mode choke coil.

In the above-mentioned embodiment, the compression section 31 is not limited to a scroll type, and may be, for example, a piston type or a vane type.
In the above embodiment, the electric compressor 10 is used in the vehicle air-conditioning system 100, but the present invention is not limited to this. For example, the electric compressor 10 may be mounted on a fuel cell vehicle and may compress air, which serves as a fluid to be supplied to the fuel cell, by the compression unit 31.

B...electricity storage device which is a power source, 10...electric compressor, 31...compression section, 32...electric motor, 36...connector, 40...inverter device, 41...circuit board, 42...inverter circuit, 44...filter circuit, 46...coil, 47...first capacitor, 48...second capacitor, 53...third conductive pattern which is a conductive pattern, 56...slit, 57...insulating section.

Claims (1)

A compression section that compresses the fluid;
an electric motor that drives the compression unit;
an inverter device having a circuit board for driving the electric motor;
a connector electrically connected to a power source;
The inverter device is
an inverter circuit that converts DC power input from the power source through the connector into AC power;
a filter circuit provided on the connector side of the inverter circuit and configured to reduce noise;
The filter circuit includes:
A coil and
a first capacitor provided on the connector side with respect to the coil;
a second capacitor provided on the inverter circuit side with respect to the coil,
the coil, the first capacitor, and the second capacitor are mounted on the circuit board;
the circuit board has a conductive pattern that electrically connects the first capacitor and the second capacitor;
a bolt passes through the conductive pattern, and the first capacitor and the second capacitor are connected to ground via the same bolt ;
the circuit board has an insulating portion that makes an impedance between the first capacitor and the second capacitor in the conductive pattern larger than an impedance between the second capacitor and the ground in the conductive pattern ,
the conductive pattern has a slit extending from between the first capacitor and the second capacitor toward the bolt,
a current path between the first capacitor and the second capacitor in the conductive pattern is formed longer than a current path between the second capacitor and the bolt in the conductive pattern;
The electric compressor , wherein the slit constitutes the insulating portion .

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