CN116567874A

CN116567874A - PTC heater and air conditioner of new energy automobile air conditioner

Info

Publication number: CN116567874A
Application number: CN202310589801.5A
Authority: CN
Inventors: 周玮; 万伟伟; 王坤; 王玮; 孙雨
Original assignee: Xiaogan Huagong Gaoli Electron Co Ltd
Current assignee: Xiaogan Huagong Gaoli Electron Co Ltd
Priority date: 2023-05-24
Filing date: 2023-05-24
Publication date: 2023-08-08

Abstract

The invention belongs to the technical field of electric heaters, and discloses a PTC heater of a new energy automobile air conditioner, which comprises a heating core body, a shell and a control box, wherein the heating core body is arranged in the shell and comprises a plurality of heating rods and a plurality of radiators, each heating rod comprises a PTC heating chip and electrode plates at two sides of the PTC heating chip, each heating rod is positioned between two adjacent radiators, a controller and a current collector are arranged in the control box, a control element for controlling the power of the heating rod is arranged on the controller, and electrodes of the heating rods extend into the control box and are electrically connected with the control element through the current collector. The invention can effectively solve the heating problem of the new energy automobile and has the characteristics of high heating speed, adjustable heating power, high protection level and the like.

Description

PTC heater and air conditioner of new energy automobile air conditioner

Technical Field

The invention belongs to the field of electric heaters, and particularly relates to a PTC heater of a new energy automobile air conditioner.

Background

New energy automobiles are the direction of global future automobile development and are the direction of important support of national policies. Because of the difference of power systems, the traditional heating mode is not suitable for new energy automobiles, and the electric heating function of the PTC ceramics just meets the requirement, so the PTC ceramics are widely used for the new energy automobiles. The PTC is used as a positive temperature coefficient semiconductor material, can self-heat in an electrified state, can self-adaptively adjust heating power according to the ambient temperature, can not overheat at the same time, and has the advantages of constant temperature, no open fire, safety, environmental protection and the like.

Although the PTC heater can autonomously control the heating power depending on its own characteristics, the temperature requirement of the user may vary from person to person in the actual situation, and the PTC heater of the automatic control may not fully satisfy the actual requirement of the user, resulting in low user experience comfort.

Disclosure of Invention

The invention aims to solve the heating problem of the new energy automobile and provides the PTC heater of the air conditioner of the new energy automobile, which can control heating power and execute turn-off protection.

In order to achieve the above purpose, the invention provides a PTC heater of a new energy automobile air conditioner, which comprises a heating core body, a shell and a control box, wherein the heating core body is arranged in the shell, the heating core body comprises a plurality of heating rods and a plurality of radiators, each heating rod comprises a PTC heating chip and electrode plates at two sides of the PTC heating chip, each heating rod is positioned between two adjacent radiators, a controller and a current collector are arranged in the control box, a control element for controlling the power of the heating rod is arranged on the controller, and the electrodes of the heating rods extend into the control box and are electrically connected with the control element through the current collector.

Specifically, the heating rods are divided into at least two groups, the busbar comprises a public busbar and at least two negative electrode busbars, wherein the positive electrodes of the heating rods are connected to the positive electrode of the control element through the public busbar, the negative electrode busbars are in one-to-one correspondence with the negative electrodes of the heating rods of each group, and the negative electrodes of the heating rods of each group are connected to the negative electrode of the control element through the corresponding negative electrode busbar.

Specifically, the heating rod is divided into two groups, the number of corresponding negative electrode bus plates is two, the number of the corresponding negative electrode bus plates is two, the corresponding negative electrode bus plates are a first bus plate and a second bus plate, the control element comprises a first IGBT, a second IGBT, a third IGBT and a fourth IGBT, the first IGBT and the second IGBT are electrically connected with the positive electrode of the heating rod through the common electrode bus plates, and the third IGBT and the fourth IGBT are electrically connected with the corresponding negative electrode of the heating rod group through the first bus plate and the second bus plate.

Specifically, the gates of the first IGBT and the second IGBT are connected with a high-side drive, and the gates of the third IGBT and the fourth IGBT are respectively connected with a first low-side drive and a second low-side drive.

Specifically, the casing includes left framework and right framework that can lock butt joint each other, and protection cross grid has all been seted up to left framework and right framework ventilation face and respectively with the control box can dismantle the connection.

Specifically, the control box opening part is provided with a groove for installing the control box cover plate, and the connection part of the control box and the cover plate and the heating core body is provided with a first sealing piece.

Specifically, still be equipped with waterproof ventilative valve, crimping plug-in components and pencil sealing plug on the control box, the three with the control box junction all is equipped with the second sealing member.

Specifically, the control box is connected with high-voltage wire harness, high-voltage wire harness one end pass through pencil sealing plug sealing connection in the control box, other end installation connector mount pad and mount pad apron.

The invention also provides a new energy automobile air conditioner, which comprises the PTC heater.

The invention also provides a control method of the PTC heater of the new energy air conditioner, comprising a conventional control S1 and a fault control S2, wherein the heating rods are divided into two groups, the first IGBT and the second IGBT are both connected to the anodes of the two groups of heating rods, the third IGBT is connected to the cathodes of one group of heating rods, and the fourth IGBT is connected to the cathodes of the other group of heating rods;

conventional control S1: accessing a whole vehicle power supply, and checking a power request; after receiving the power request, the high-side drive outputs a high level to enable the first IGBT and the second IGBT to be conducted, and the first low-side drive and the second low-side drive output PWM signals to enable the third IGBT and the fourth IGBT to be conducted; the heating rod is conducted, and the required heating power is output;

fault control S2: and when the third IGBT and the fourth IGBT are in fault, the high-side drive outputs a low level, the first IGBT and the second IGBT are cut off, and the first IGBT and the second IGBT enter a cut-off protection state.

Compared with the prior art, the invention has the following advantages and beneficial effects:

the PTC heater of the new energy automobile air conditioner has the advantages that the structure is simplified, the protection level is high, the high-temperature-resistant insulating sealing elements are arranged at the joints of the control box and the heating core body, and the integral protection level can reach IP67; the shell is provided with a protection cross grid, and the protection grade of the heater part can reach IPXXB; the PTC heating power can be controlled according to the PTC self characteristic and PWM, and turn-off protection is additionally arranged, so that the heater is safe and controllable in heating.

The present invention will be described in further detail with reference to the accompanying drawings.

Drawings

Fig. 1 is an exploded view schematically showing a PTC heater of a new energy vehicle air conditioner according to the present invention;

fig. 2 is a detailed view of the PTC heater controller and the bus plate of the new energy automobile air conditioner provided by the invention;

FIG. 3 is an overall assembly diagram of the PTC heater of the air conditioner of the new energy automobile provided by the invention;

fig. 4 is a schematic circuit diagram of the electrical connection between the heating core electrode and the control element of the PTC heater for the new energy automobile air conditioner.

Reference numerals illustrate: 1. a cover plate; 2. a control box; 3. a low voltage connector; 4. a high voltage harness; 5. a ground wire harness; 6. a left frame; 7. a right frame; 8. a heating core; 9. a controller; 10. a PTC heating chip; 11. an electrode sheet; 12. a heating rod; 13. a heat sink; 14. a ventilation valve; 15. a connector mount; 16. a mounting seat cover plate; 17. a harness sealing plug; 18. an IGBT mounting bracket; 19. a busbar mounting bracket; 20. a first bus bar; 21. a second bus bar; 22. a common electrode collector sheet; 23. a first IGBT; 24. a second IGBT; 25. a third IGBT; 26. and a fourth IGBT.

Description of the embodiments

The technical solutions of the present invention will be clearly and completely described in the following examples, and it is obvious that the described examples are only some examples of the present invention, but not all examples. Although representative embodiments of the present invention have been described in detail, those skilled in the art to which the invention pertains will appreciate that various modifications and changes can be made without departing from the scope of the invention. Accordingly, the scope of the invention should not be limited to the embodiments, but should be defined by the appended claims and equivalents thereof.

Referring to fig. 1 and 2, the embodiment of the invention provides a PTC heater for a new energy vehicle air conditioner, which comprises a housing, a heating core 8 and a control box 2;

the heating core body 8 comprises a heating rod 12 and a radiator 13, the heating rod 12 is formed by clamping two poles of the PTC heating chip 10 by two electrode plates 11, a positive electrode and a negative electrode are led out from one end of the control box 2 by the heating rod 12, and the positive electrode and the negative electrode are called as positive electrode and negative electrode according to the electric potential connected to the controller; the heat radiator 13 is arranged between the heating rods 12 at intervals, and the heat radiator 13 has good heat conductivity, and the heat is conducted by clinging to the heating rods 12, so that the heater rapidly releases heat, the heating rate is improved, and meanwhile, the heat radiator has the characteristics of reliability, environmental protection, manufacturability and the like. The control box 2 is internally provided with a controller 9 and a confluence device, a heating core 8 penetrates into the control box 2, the penetrating part comprises electrodes at two ends of a heating rod 12, the positive electrode and the negative electrode of the heating rod 12 are connected with the controller 9 through the confluence device, and the controller 9 adjusts heating power and executes turn-off protection by controlling the positive and negative electrode potential of the heating rod 12.

Optimizing the above embodiment, the current collector includes a first current collector sheet 20, a second current collector sheet 21, and a common electrode current collector sheet 22, where the first current collector sheet 20 and the second current collector sheet 21 are negative electrode current collector sheets; the controller comprises a first IGBT23, a second IGBT24, a third IGBT25 and a fourth IGBT26, wherein the first IGBT23 and the second IGBT24 are high-level IGBTs and are used for executing turn-off protection when the third IGBT25 and the fourth IGBT26 are in fault; the third IGBT25 and the fourth IGBT26 are low-level IGBTs, and function to control heater power. In a preferred embodiment, in order to prevent the total current from being too large and possibly exceeding the current-resistant level of the IGBTs, the controller 9 is provided with two high-level IGBTs for shunting, and the high-level IGBTs 23 and 24 correspond to the first busbar 22 and are positioned at the positive electrode of the whole vehicle input. Further, in order to accurately control the power of the heater, the heating rod 12 is divided into two parts, wherein the negative electrode of one part of the heating rod 12 is welded with the first bus bar 20, the negative electrode of the other part of the heating rod 12 is welded with the second bus bar 21, the first bus bar 20 and the second bus bar 21 are respectively welded on a third IGBT25 and a fourth IGBT26 on the controller correspondingly, the IGBT25 and the IGBT26 are positioned at the negative electrode of the whole vehicle input, and the heating power of the heater is controlled by respectively controlling the on-off state of the IGBT25 and the IGBT 26. In this embodiment, a busbar mounting bracket 19 is further disposed in the control box 2, and is used for arranging and fixing the busbar plates, and an IGBT mounting bracket 18 is used for arranging and fixing the four IGBTs below the controller 9.

Optimizing above-mentioned embodiment, the casing includes two left framework 6 and right framework 7 that can lock butt joint each other, and the casing is equipped with the fixed hole site of mutual block all around, and left and right framework is dismantled with the control box by the bolt respectively and is connected. The shell can adopt a high-temperature-resistant PBT modified material, such as PBT+GF30, a cross grid is formed on the ventilation surface, and operators are protected by isolating the heating core body 8, so that the IPXXB protection level is integrally met. Further, one end part of the heating core body 8 in the shell penetrates into the control box 2, a first sealing piece is arranged in an area which is matched with the control box 2, the first sealing piece is high-temperature-resistant insulating sealant, can be liquid silica gel, stands after the sealant is filled, and is sealed after solidification, and the sealing structure meets the IP67 protection level.

In optimizing the above embodiment, the top of the control box 2 is also provided with a groove for installing the cover plate 1, and the embedded position of the control box 2 and the cover plate 1 is also provided with a first sealing piece for sealing. A plurality of functional connectors have been seted up to control box 2 side, for promoting the whole security of box body, increase on the control box 2 and be equipped with low pressure connector 3, be used for shutoff control box 2's the waterproof ventilative valve 14 of louvre, the one end of high-voltage harness 4 passes through pencil sealing plug 17 and connects control box 2, low pressure connector 3, waterproof ventilative valve 14 and pencil sealing plug 17 and control box 2 junction all accomplish sealedly through the second sealing member, the second sealing member is terminal surface seal rubber ring, high-voltage harness 4 main part covers has insulating rubber, the other end is accomplished sealedly through connector mount pad 15 and mount pad apron 16, above-mentioned seal structure all satisfies IP67 protection level.

As shown in fig. 3, the control box 2 is further connected with a high-voltage harness 4 for voltage input of the heater and a grounding harness 5 for grounding protection.

Referring to fig. 4, according to the connection manner of the heating rod anode and the bus bar, the integration of the heating rod connected with the first bus bar into PTC1 and the integration of the other part of the heating rod connected with the second bus bar into PTC2 are shown in the figure. HV+ is the positive input of the whole vehicle, the first IGBT23 and the second IGBT24 are connected in parallel, the potential of the c pole is equal to HV+, the g pole is connected with the positive poles of the positive poles PTC1 and PTC2 in a high-side driving H_driver to control on/off, the potential of the e pole is connected with the positive poles of the positive poles PTC1 and PTC2, when the heater works, the positive poles of the positive poles PTC1 and PTC2 are close to the input voltage of the whole vehicle, the e pole voltage of the IGBT at the high side is considered to be unstable, the e pole is connected to a high-voltage reference point GND_H for accurately controlling on/off of the IGBT23 and the IGBT24, the potential difference between the g pole and the e pole can be effectively identified through the potential of the reference GND_H, and the voltage difference is controlled to be between 0V and 15V, so that on/off of the IGBT23 and the IGBT24 is controlled.

The IGBT25 and the IGBT26 are respectively connected with the cathodes of the PTC1 and the PTC2, the G-side is respectively connected with the first low-side drive L_Driver1 and the second low-side drive L_Driver2, the first low-side drive and the second low-side drive control the on-off of the PTC heating chip in a time sequence through PWM signals, and the average power of the PTC is controlled according to the duty ratio.

The embodiment of the invention also provides a control mode of the PTC heater of the air conditioner of the new energy automobile, which comprises a conventional control S1 and a fault control S2,

conventional control S1: accessing a whole vehicle power supply, and checking a power request;

when no power is requested: the IGBT23, the IGBT24, the IGBT25 and the IGBT26 are all turned off, and at the moment, no pressure difference exists between the positive electrode and the negative electrode of the PTC;

when there is a power request: the IGBT23 and the IGBT24 are conducted by H_driver output high level; the IGBTs 25 and 26 are turned on only at this time, i.e., in the power request state, by the PWM high level signal output by the l_driver, and the duty ratio is adjusted according to the power demand.

Fault control S2: when the IGBT25/IGBT26 fails, the H_driver outputs a low level, and the two high-side IGBTs are cut off and enter a cut-off protection state.

In the embodiment of the invention, the number of the high-side IGBT, the low-side IGBT and the corresponding driving is determined according to the input voltage of the whole vehicle and the current-resisting level of the IGBT, and in other embodiments, the number of the control elements can be increased or decreased according to actual conditions.

Referring to fig. 1-4, an embodiment of the present invention further provides an air conditioner, which includes an air conditioner body, and further includes the PTC heater, where the PTC heater is installed in the air conditioner body. The air conditioner is suitable for heating of new energy automobiles, has the characteristics of automatic temperature adjustment, uniform heating, high protection level and the like, and has a simple structure and considerable economic benefit.

The foregoing examples are merely illustrative of the present invention and are not intended to limit the scope of the present invention, and all designs that are the same or similar to the present invention are within the scope of the present invention.

Claims

1. The utility model provides a new energy automobile air conditioner PTC heater, includes core, casing and the control box generate heat, its characterized in that have arranged the core that generates heat in the casing, the core that generates heat includes a plurality of heating rods and a plurality of radiator, the heating rod includes PTC heating chip and both sides electrode slice, every the heating rod is located between two adjacent radiators, be provided with controller and collector in the control box, be equipped with the control element of control heating rod power on the controller, the electrode of heating rod stretches into in the control box and is connected with the control element electricity through the collector.

2. The PTC heater for a new energy vehicle air conditioner of claim 1 wherein the heating bars are divided into at least two groups, the busbar comprises a common busbar and at least two negative electrode busbars, wherein the positive electrodes of the heating bars are connected to the positive electrode of the control element through the common busbar, the negative electrode busbars are in one-to-one correspondence with the negative electrodes of the heating bars of each group, and the negative electrodes of the heating bars of each group are connected to the negative electrode of the control element through the corresponding negative electrode busbar.

3. The PTC heater for a new energy vehicle air conditioner of claim 2, wherein the heating rod is divided into two groups, the number of corresponding negative electrode bus bars is two, and the number of corresponding negative electrode bus bars is a first bus bar and a second bus bar, the control element comprises a first IGBT, a second IGBT, a third IGBT and a fourth IGBT, the first IGBT and the second IGBT are electrically connected with the positive electrode of the heating rod through the common electrode bus bar, and the third IGBT and the fourth IGBT are electrically connected with the negative electrode of the corresponding heating rod group through the first bus bar and the second bus bar, respectively.

4. The PTC heater for a new energy vehicle air conditioner of claim 3 wherein the gates of the first IGBT and the second IGBT are connected with a high side drive, and the gates of the third IGBT and the fourth IGBT are connected with a first low side drive and a second low side drive, respectively.

5. The PTC heater for a new energy vehicle air conditioner of claim 1, wherein the housing comprises a left frame and a right frame which can be fastened and abutted to each other, and the ventilation surfaces of the left frame and the right frame are provided with a protection cross grid and are detachably connected with the control box respectively.

6. The PTC heater for air conditioner of new energy vehicle as claimed in claim 1, wherein the opening of the control box is provided with a groove for installing the cover plate of the control box, and the connection parts of the control box, the cover plate and the heating core are provided with a first sealing member.

7. The PTC heater for a new energy vehicle air conditioner of claim 6 wherein the control box is further provided with a waterproof vent valve, a crimp connector and a wire harness sealing plug, and wherein the junction of the three and the control box is provided with a second sealing member.

8. The PTC heater for a new energy vehicle air conditioner of claim 7 wherein the control box is connected with a high voltage harness, one end of the high voltage harness is sealingly connected to the control box by a harness sealing plug, and the other end is provided with a connector mounting seat and a mounting seat cover plate.

9. A new energy vehicle air conditioner comprising an air conditioner body, and further comprising a PTC heater according to any one of claims 1 to 8, wherein the PTC heater is installed in the air conditioner body.

10. The control method of the PTC heater of the new energy air conditioner is characterized by comprising a conventional control S1 and a fault control S2, wherein heating rods are divided into two groups, a first IGBT and a second IGBT are connected to the anodes of the two groups of heating rods, a third IGBT is connected to the cathodes of one group of heating rods, and a fourth IGBT is connected to the cathodes of the other group of heating rods;