WO2014032593A1

WO2014032593A1 - Liquid-cooled motor controller

Info

Publication number: WO2014032593A1
Application number: PCT/CN2013/082470
Authority: WO
Inventors: 陈夏新
Original assignee: Chen Xiaxin
Priority date: 2012-09-01
Filing date: 2013-08-28
Publication date: 2014-03-06

Abstract

The present invention belongs to the technical field of motor controllers and relates to a liquid-cooled motor controller. A circuit board of the motor controller, containing power devices is supported in a closed metal box in an insulating manner; an insulating and heat conducting liquid fills the metal box; a space for heat expansion of the liquid is arranged between the inner wall of the metal box and the liquid; and a lead wire connected to the motor controller is led out of the metal box in an insulating and sealing manner. The present invention has the following advantages of using the liquid to conduct heat outwards, high heat transfer efficiency, high heat dissipation speed, good insulating property and long service life, and having suitability for manufacturing motor controllers with high reliability.

Description

TECHNICAL FIELD The present invention relates to the field of motor controller technology, and particularly to a liquid-cooled motor controller.

Background technique

The power device currently used in the motor controller is a field effect transistor or an IGBT, etc.

The heat generated by the work is thermally conducted by pressing against the metal conductor. Power devices and metal heat sinks must be insulated from each other by insulation such as insulating sheets. This type of thermal conduction involves the pressing installation of power devices and metal heat conductors and the handling of insulation problems. And because of the current technical constraints, to achieve the purpose of the motor controller, the number of required power devices from 6 to 48 books

Between the six and 48 power devices, it is necessary to press on the metal heat conductor, and it is required to be insulated from the metal heat conductor. The processing process is complicated and the heat conduction effect is not good.

Summary of the invention

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid-cooled motor controller having a good insulation and heat dissipation and a single processing process.

The object of the invention is achieved in this way:

The liquid-cooled motor controller insulates a circuit board of a motor controller including a power device in a closed metal case, and the metal case is filled with an insulating and heat-conducting liquid, and a thermal expansion of the liquid is provided between the inner wall of the metal case and the liquid. Space, connect the motor controller to the wire insulation seal of the lead-out metal box.

The above liquid is an insulating heat conductive transformer oil or insulating oil or silicone oil or heat transfer oil or other liquid having insulating and heat conducting characteristics.

The thermal energy generated by the operation of the power device on the motor controller circuit board is transmitted to the metal case through the insulating and heat-conducting liquid, and then naturally convectively dissipated by the air through the metal case.

The top wall of the metal case and the high current metal conductive post are insulated by an insulating mat and sealed with a gasket. The lead wires of the above motor controller circuit board are sealed by a sealing device to take out the metal case. Still another object of the present invention is to provide a liquid-cooled motor controller to solve the problem that air in the casing is reserved for liquid expansion and contraction, and the sealing property in the entire metal case is liable to cause problems, thereby easily causing oil leakage. Technical problem.

The object of the invention is achieved in this way:

The liquid-cooled motor controller insulates a circuit board of a motor controller including a power device in a closed box body, and the box body is filled with an insulating and heat-conducting liquid, and at least one pressure balance device is arranged inside, outside and on the box body In order to balance the internal and external pressure difference generated when the insulating thermal fluid is thermally expanded and contracted in the sealed casing;

The pressure balance device is disposed inside the box body and communicates with the outside air, and the pressure balance device is sealed with the outer box of the sealed box. When the insulating and heat conducting liquid is heated and expanded, the air in the pressure balance device is discharged to the outside of the pressure balance device, and the inner insulation is performed. After the temperature of the heat transfer liquid drops, the volume of the insulating heat transfer liquid becomes smaller, and the external air is replenished back into the pressure balance device; or

The pressure balance device is disposed outside the casing, and penetrates with the seal box. The insulated heat transfer liquid is heated and expanded to the external pressure balance device. After the temperature drops, the insulated heat transfer liquid in the pressure balance device returns to the sealed box.

One solution is as follows: The pressure balance device is a gas chamber provided in the sealed box, and the gas port is connected with the outside air, and the extension of the gas port is sealed with the box of the sealed box. When the controller is in operation, the insulating heat transfer liquid is heated and expanded. After that, the air squeezing is squeezed to deform the air enthalpy, and the air in the air enthalpy is discharged outside the air vent. When the temperature of the internal insulating heat conductive liquid drops, the volume of the insulating heat conductive liquid becomes small, and the external air is replenished into the air enthalpy.

The second scheme is as follows: The pressure balance device is a gas vent on the sealed box or the outside, the extension of the gas vent is sealed with the box of the sealed box, the gas enthalpy and the sealed box are penetrated, and the insulating heat conductive liquid is heated and expanded, and is flooded to the outside. The gas is suffocating, the gas enthalpy becomes larger, and after the temperature drops, the gas enthalpy becomes smaller, and the insulating and heat-conducting liquid in the gas sputum returns to the sealed box. The pressure equalization device may also include a balancing air pressure device using a piston.

The liquid-cooled motor controller insulates the circuit board of the motor controller including the power device in a closed box body, and the box body is filled with an insulating and heat-conducting liquid, and a liquid thermal expansion space is arranged between the inner wall of the box and the liquid. Connect the wire of the motor controller to the outside of the lead-out box.

The thermal energy generated by the operation of the power device on the motor controller circuit board is transmitted to the metal surface through the insulating and heat-conducting liquid, and is naturally convected by the metal surface through the metal surface.

The small current lead of the above motor controller circuit board is sealed by a sealing device to take out the case.

The technical effects of the present invention that are outstanding and beneficial over the prior art are:

1. The invention adopts liquid to conduct heat to the outside, and the processing process has a single tube and good thermal conductivity.

2. The invention adopts the insulating and heat-conducting liquid to transfer the heat generated by the power device of the motor controller to the metal box wall from all directions, the heat transfer efficiency is high, the heat dissipation is fast, and the temperature rise of the motor controller is much slower than the conventional method. It ensures the normal operation of the controller and long service life.

3. The invention adopts insulating and heat-conducting liquid, and its insulating performance is superior to insulating materials such as insulating paper and insulating mat. This is because insulating materials such as insulating paper and insulating mat are easy to cause insulation hazard in manufacturing, installation and maintenance.

4. The power device on the motor controller circuit board of the present invention does not need to be fastened with the metal heat conductor, and the current technical reasons are generally more than 6 or even as many as 48, thereby greatly reducing the number of power devices. The processing workload. In addition, the power device on the motor controller circuit board of the present invention may be in tight contact with the metal housing or may not be in firm contact with the metal housing.

5. The high current connection of the present invention can be directly led out from the corresponding electrical connection point on the motor controller circuit board by the metal conductive column, thereby minimizing the electrical loss.

6. The high-current-connected metal conductive column of the present invention can be directly mounted on the top of the motor controller, and the process of fixing the wiring to the conventional method is eliminated when the motor is assembled.

7. The metal conductive column of the high current connection of the invention can be supported by the card slot or the column of the metal box. The body can also fix the circuit board of the motor controller, thus reducing the installation process.

8. The present invention is applicable to a highly reliable motor controller.

9. The invention provides at least one device for balancing pressure on the inside, the outside, and the box body of the casing to balance the internal and external pressure difference generated when the insulating thermal fluid is thermally expanded and contracted in the sealed casing body. With this pressure balance device, The insulating thermal fluid has a space for thermal expansion and contraction, so that no particularly large pressure difference is generated inside the casing, and the casing is easy to achieve sealing.

10. The pressure equalization device of the present invention may be provided in one or more, particularly in accordance with a pressure difference that may occur, when a plurality of pressure equalization devices are disposed inside or outside the casing, the pressure balance devices may exist in separate manners. The inside or outside of the box can achieve better sealing effect, especially according to the liquid-cooled motor controller to set different pressure equalization devices at different positions to achieve the internal pressure balance effect, especially when a certain pressure When the balancing device fails, it does not affect the overall pressure difference. The pressure equalization device can also be present in series or inside the casing in a series manner, as well as achieving a sealing effect. Of course, the present invention can also improve the thermal conductivity by using a liquid outward heat conduction without providing a pressure balance device. DRAWINGS

Figure 1 is a schematic cross-sectional view showing a non-decompression device of the present invention;

Figure 2 is a cross-sectional view showing a second embodiment of the present invention;

Figure 3 is a cross-sectional view showing a third example of the present invention;

Figure 4A is a side elevational view of the entirety of the outer casing of the fourth embodiment of the present invention;

Figure 4B is a front elevational view of the entire outer casing of the fourth embodiment of the present invention;

5 and FIG. 6 are diagrams showing an example of the extension of the inner gas vent and the sealing of the casing of the sealed box in the fifth embodiment of the present invention;

Fig. 7 is a view showing an example of the structure inside the fifth embodiment of the present invention.

8A and 8B are two different state diagrams of another embodiment of the pressure equalization device, respectively. detailed description

Embodiment 1

The present invention will be further described in the following with reference to the accompanying drawings, FIG.

The liquid-cooled motor controller insulates the circuit board 2 of the motor controller 16 including the power device in the closed metal case 15, and the metal case 15 is filled with the insulating and heat-conducting liquid 11, the inner wall of the metal case 15 and the liquid 11 A thermal expansion space 10 is provided between the liquid, and the lead wire 14 connected to the motor controller 16 is insulated and sealed from the lead metal case 15.

At least three sides of the metal case 15 described above are boxes made of aluminum or copper. Of course, at least three sides of the metal case 15 are boxes made of aluminum or copper. This design has better heat dissipation, but generally only A box made of aluminum or copper is involved.

The above liquid 11 is an insulating heat conductive transformer oil or insulating oil or silicone oil or heat transfer oil or other liquid having insulating and heat conducting characteristics.

The thermal energy generated by the operation of the power device 9 on the circuit board 2 of the above motor controller 16 is transmitted to the metal case 15 through the insulating and thermally conductive liquid 11, and is then naturally convected by the metal case 15 to dissipate heat.

The circuit board 2 of the controller 16 insulates the circuit board 2 of the motor controller 16 in a closed metal box through the metal conductive post 7 on the top wall 5 and the nut 1 and the card slots 4 on the side walls 12, 17. In the case of 15, the card slot 4 is formed by a horizontal U-shaped body 3 fixed on the two side walls 12, 17 of the metal case or by a splint provided on the upper and lower sides of the circuit board 2 and fixed on the side walls 12, 17 of the metal case. form. This is merely an illustration and is not intended to be limited to the invention.

The top wall 5 of the metal case 15 and the high-current metal conductive column 7 are insulated by an insulating mat 6 and sealed with an epoxy resin and a gasket, and fixed by a nut 8, and the metal conductive column 7 is respectively controlled by a motor. The power input connection point on the circuit board 2 and the three-phase connection point of the drive motor are electrically connected. The sealing of epoxy resin and gasket is one of the more common sealing methods, but this method is not unique. The existing common sealing methods should also fall within the scope of protection of the present invention. The small current lead 14 (for example, the signal line) of the motor controller circuit board 2 described above is sealed by the sealing device 13 to be taken out of the metal case 15 or electrically connected to the socket provided on the side wall 12 of the metal case, and the side wall 12 of the metal case is Sealing between sockets.

The invention can be conveniently implemented for motor controllers such as two-wheel, three-wheel, four-wheel electric vehicles and forklifts. The above embodiment is only a preferred embodiment of the present invention in a 24 field effect tube electric vehicle motor controller (Note: only 12 field effect tubes are shown in the drawing, and another 12 field effect tubes and figures are shown. It is symmetrically arranged, not shown in the figure). The scope of the present invention is not limited thereto, and all equivalent changes made by the structure, shape, size, and principle of the present invention are intended to be included in the scope of the present invention. Embodiment 2

The present invention will be further described below with reference to the accompanying drawings in which: FIG.

The liquid-cooled motor controller insulates the circuit board 2 of the motor controller 16 including the power device in the closed casing 15, and the casing 15 is filled with an insulating and heat-conducting liquid 11 connected to the wire 14 of the motor controller 16 for insulation. The sealed take-out case 15 is outside.

At least one balance pressure device is arranged on the inner and outer parts of the casing, and the metal box body is balanced to balance the internal and external pressure difference generated when the insulating thermal fluid is thermally expanded and contracted in the sealed casing.

The pressure balance device is disposed inside the box body and communicates with the outside air, and the pressure balance device is sealed with the sealed box. When the insulating heat transfer liquid is heated and expanded, the air in the pressure balance device is discharged to the outside of the pressure balance device, and the temperature of the internal insulated heat conductive liquid After the lowering, the volume of the insulating and thermally conductive liquid becomes smaller, and the external air is replenished back into the pressure balance device; or

One solution is: the pressure balance device is a gas cylinder 19 (shown in FIG. 2) provided in one or more sealed boxes, the gas port is connected to the outside air, and the extension of the gas port is sealed with the casing of the sealed box. When the controller is in working state, after the insulating and heat-conducting liquid is heated and expanded, the air enthalpy is squeezed to deform the air enthalpy, and the air in the air enthalpy is discharged outside the air vent. When the temperature of the internal insulating heat-conductive liquid drops, the volume of the insulating heat-conductive liquid becomes smaller. The outside air is replenished inside the air. When there are a plurality of gas cylinders 19, the gas cylinders 19 can be independent of each other, and each of the gas cylinders 19 is disposed in the sealed box, but the sealing box is provided with a corresponding through hole, and the mouth of the gas cylinder 19 passes through the corresponding through hole, and the outside air Connected, and, the gas vent and the through hole of the sealed box are sealed to ensure that the sealed box does not leak due to the through hole, and the mouth of the gas vent 19 ensures communication with the outside air, and some may be provided. Convenient access to the air plug. The gas cylinders 19 can be independent of each other, so that when there is a problem with one of the gas cylinders, the overall pressure balance is not affected. Also, the gas cylinders 19 can be independently disposed at different positions in the sealed box, especially when there are different pressure differences in the sealed box, the different sizes of the gas cylinders 19 are disposed at corresponding positions to achieve the overall pressure balance effect.

When the number of the air cylinders 19 is plural, the air cylinders 19 can communicate with each other, and a through hole is formed in the sealed casing, and the port of one of the air cylinders 19 communicates with the outside air through the through holes. These two methods can greatly improve the balance. Embodiment 3

The second scheme is as follows: The pressure balance device is a gas cylinder 18 (shown in Figure 3) provided on or outside the sealed box. The extension of the gas port is sealed with the box of the sealed box, and the gas and seal boxes are penetrated, and the insulation is thermally conductive. After the liquid is heated and expanded, it is flooded to the external gas, and the gas enthalpy becomes larger. After the temperature drops, the gas enthalpy becomes smaller, and the insulating and heat-conducting liquid in the gas enthalpy returns to the sealed box. Similarly, the gas enthalpy 18 may be plural, and the effect is the same as the above, and will not be described again. Embodiment 4

Compared with the second and third embodiments, the present embodiment may not include the pressure balance device.

The upper and lower covers may also be metal boxes, or one of the upper and lower covers is a metal case. For example, as shown in FIG. 4A and FIG. 4B, no air entanglement may be provided on the outer casing.

In the present application, a stud is disposed on a bottom or other side of the box body, the circuit board defines a through hole, and the heat radiating surface of the power component contacts the stud passing through the through hole of the circuit board to directly pass the heat generated by the power component. The studs and the wall of the box are thermally conductive, and the studs can also be fixed. The box body is sealed and fixedly connected by the studs and the high-current metal conductive posts. In the present application, how to fix the connection is not the present invention. Focus.

Fifth embodiment

The pressure equalization device may also include a balancing air pressure device using a piston. The object of the present invention is to: insulate and support a circuit board of a motor controller including a power device in a closed casing, the casing is filled with an insulating and heat-conducting liquid, and at least one pressure of the balance pressure is set inside the casing, the outside, and the casing. The balance device, in order to balance the internal and external pressure difference caused by the thermal expansion and contraction of the insulating thermal fluid in the sealed box body, has such characteristics, and should fall within the protection scope of the present invention.

T匕: 3⁄4 port:

A certain amount of heat-conducting oil is added to the sealed box, leaving room for expansion of the heat-conducting oil after temperature rise. This space can have air, which can be vacuum. In the case of air, the internal pressure will become larger after temperature rise, resulting in sealing. The difficulty becomes higher, and there is also a way to set the air box in the sealed box, the air port is connected with the outside air, and the extension 36 of the gas port is sealed with the box of the sealed box (as shown in Fig. 6), when the product works, heat conduction After the oil is heated and expanded, the gas is squeezed to deform the gas, and the air in the gas is discharged outside the gas mouth. When the temperature of the internal heat transfer oil drops, the volume of the heat transfer oil becomes smaller, and the external air is replenished into the gas, so that The pressure inside and outside the sealed box is the same. The principle of the external air enthalpy is that the extension of the gas vent is sealed with the box of the sealed box, and the gas enthalpy and the sealing box are penetrated. After the heat transfer oil is heated and expanded, it is flooded to the outside air, and the gas suffocation becomes large. After the temperature drops, the gas enthalpy becomes smaller, and the heat transfer oil in the gas sump returns to the sealed box. Another way is to use a device such as a piston to balance the air pressure.

The pressure balance device is disposed outside the box body, and a pressure valve body is disposed at a position penetrating the seal box to achieve a valve body whose pressure in the seal box is greater than a threshold value and opens to the pressure balance device, otherwise the valve body is opened. The effect of flowing to the valve body of the sealed box.

The pressure equalization device may also be not only a gas cartridge provided on or outside the sealed box, but may be other devices such as a software device.

The software device is disposed inside or outside the sealed box (see Fig. 8B), and the software device can increase the volume inside the sealed box or reduce the volume inside the sealed box by moving its position. It may be a soft rubber-like device on one side of the casing. Before heating, the software device 37 is convex inward (Fig. 8A), that is, convex toward the liquid portion (inwardly convex portion in Fig. 8A), after heating , like a soft rubber, it bounces to the side, the soft body device 37 is convex outward (as shown in Fig. 8B), that is, it can be decompressed to a portion without liquid, and one side is perforated, and the external air can also be connected. The effect of achieving pressure balance.

The invention can be conveniently implemented for motor controllers such as two-wheel, three-wheel, four-wheel electric vehicles, forklifts and electric vehicles. The above embodiments are only preferred embodiments of the present invention in an electric vehicle motor controller, and are not intended to limit the scope of the present invention. Therefore, the structure, shape, size, principle, etc. according to the present invention are The effect changes should be covered by the scope of the present invention.

Referring to FIG. 5 to FIG. 7, the circuit board of FIG. 7 is insulated and supported in the outer casing of FIG. 6. The outer casing of FIG. 6 is provided with an insulating thermal fluid, and the thermal expansion and contraction of the insulating thermal fluid is balanced by the airflow of FIG. pressure.

In this example, the structure of the casing 31 and the outer casing 32 is not critical, and the present invention is mainly provided with a pressure balancing device for balancing the pressure difference in the casing.

The preferred embodiments of the invention are only intended to aid in the description of the invention. The preferred embodiments are not intended to be exhaustive or to limit the details of the invention. Obviously, many modifications and variations are possible in light of the contents of this specification. The present invention has been chosen and described in detail to explain the principles and embodiments of the present invention. The invention is to be limited only by the scope of the appended claims and the appended claims.

Claims

Claim

1. A liquid-cooled motor controller, characterized in that: a circuit board of a motor controller including a power device is insulated and supported in a closed metal case, and the metal case is filled with an insulating and heat-conducting liquid, between the inner wall of the metal case and the liquid A thermal expansion space is provided for the liquid, and the wire of the motor controller is insulated from the lead-out metal case.

2. The liquid-cooled motor controller according to claim 1, wherein: the liquid is an insulating heat conductive transformer oil or an insulating oil or a silicone oil or a heat transfer oil or other liquid having an insulating and heat conducting property.

3. The liquid-cooled motor controller according to claim 1, wherein: the thermal energy generated by the operation of the power device on the circuit board of the motor controller is transmitted to the metal case through the insulating and heat-conducting liquid, and then passed through the metal case. Use air to convect heat naturally.

4. The liquid-cooled motor controller according to claim 1, wherein: the top wall of the metal case and the high-current metal conductive post are insulated by an insulating mat and sealed with a gasket.

5. The liquid-cooled motor controller according to claim 1, wherein: the lead wire of the motor controller circuit board is sealed by a sealing device to take out the metal case.

6. A liquid-cooled motor controller, characterized in that a circuit board of a motor controller including a power device is insulated and supported in a closed casing, and the casing is filled with an insulating and heat-conducting liquid, inside, outside, and box of the casing At least one pressure equalizing device for balancing pressure is disposed on the body to balance the internal and external pressure difference generated when the insulating thermal fluid is thermally expanded and contracted in the sealed casing body.

The pressure balance device is disposed outside the box body, and penetrates with the sealing box, and the insulating heat conduction liquid heats up In the expanded state, it is flooded to the external pressure balance device. After the temperature drops, the insulating and heat transfer liquid in the pressure balance device returns to the sealed box.

7. The liquid-cooled motor controller according to claim 6, wherein the pressure equalizing device is a gas vent provided in one or more sealed boxes, and the gas vent is connected to the outside air, and the gas vent is extended. The box of the sealed box is sealed. When the controller is in working condition, the insulating and heat-conducting liquid is heated and expanded, the air is squeezed, the air is deformed, and the air in the air is discharged outside the air port. When the temperature of the internal insulating heat-conducting liquid drops, The volume of the insulating and heat-conducting liquid becomes smaller, and the external air is replenished inside the gas cylinder.

8. The liquid-cooled motor controller according to claim 6, wherein the pressure balance device is one or more air bubbles disposed on or outside the sealed box, and the extension of the gas port is sealed with the outer casing of the sealed box. The gas enthalpy and the sealing box penetrate, and after the insulating and heat-conducting liquid is heated and expanded, it is flooded to the external gas, and the gas enthalpy becomes large. After the temperature is lowered, the gas enthalpy becomes smaller, and the insulating and heat-conducting liquid in the gas enthalpy returns to the sealed box.

The liquid-cooled motor controller according to claim 6, wherein the pressure balance device further comprises a balance air pressure device using the piston.

The liquid-cooled motor controller according to claim 6, wherein the pressure balance device is disposed outside the casing, and a pressure valve body is disposed at a position penetrating the seal box to achieve a pressure greater than that in the seal box. A threshold opens the valve body that flows to the pressure equalization device, otherwise it opens the valve body that flows to the seal box.

11. The liquid-cooled motor controller according to claim 6 or 7, wherein: the thermal energy generated by the operation of the power device on the motor controller circuit board is transferred to the metal-made side through the insulating and heat-conductive liquid. The box body is then convectively cooled by air using a metal surface.

12. An electric vehicle comprising a liquid-cooled motor controller of claims 1 to 11.