CN210591424U

CN210591424U - Electric automobile driving system and electric automobile

Info

Publication number: CN210591424U
Application number: CN201921505572.XU
Authority: CN
Inventors: 邓小武
Original assignee: Changsha Niumi Drive Technology Co Ltd
Current assignee: Changsha Niumi Drive Technology Co Ltd
Priority date: 2019-09-10
Filing date: 2019-09-10
Publication date: 2020-05-22
Anticipated expiration: 2029-09-10

Abstract

The utility model discloses an electric automobile driving system, including a plurality of contravariant units and driving motor, a plurality of coils in each phase stator winding of driving motor divide into the multiunit, form the multicomponent winding, each the branch winding is three-phase winding, branch winding and contravariant unit quantity equal, the three-phase input of a component winding corresponds with the three-phase output of an contravariant unit and links to each other, each the contravariant unit is the three-phase full-bridge structure that comprises discrete switching element. The utility model discloses still correspondingly disclose an electric automobile, include as above electric automobile actuating system. The utility model discloses an electric automobile actuating system and electric automobile all have compact structure, with low costs, the reliability is high, advantages such as heat dispersion is good.

Description

Electric automobile driving system and electric automobile

Technical Field

The utility model relates to an electric automobile technical field refers in particular to an electric automobile actuating system and electric automobile.

Background

The electric automobile driving system generally comprises a driving motor and a motor controller, wherein the driving motor generally adopts a three-phase alternating current motor at present, and the motor controller generally adopts a main circuit structure based on a three-phase full-bridge structure. Fig. 1 shows a schematic diagram of a main circuit of a three-phase alternating-current drive motor and a motor controller. In fig. 1, the direct current output from the battery enters the motor controller through DC + and DC-, and the motor controller inverts the direct current input from the battery into three-phase alternating current through a three-phase full-bridge inverter circuit composed of 6 switching tubes (1-6 #) and respectively enters the driving motor 2 through U, V and W to supply power to the motor. The switching tubes (1#, 3#, 5#) form three upper tubes of the full bridge, and the switching tubes (2#, 4#, 6#) are three lower tubes of the full bridge.

Currently, IGBT modules (such as an english-flying IGBT module-FF 600R12ME4) are commonly used for switching tubes of a driving motor controller, wherein one IGBT module comprises an upper tube (1# or 3# or 5#) and a lower tube (2# or 4# or 6#) shown in fig. 1.

Fig. 2 is a schematic diagram of a main circuit inside an IGBT module, in fig. 2, a1 is a single tube formed by one IGBT chip, a2 is a single tube formed by a plurality of IGBT chips identical to a1, a1 is connected with collectors c of a2, and emitters e are connected together to form an upper tube of a three-phase inverter full bridge in parallel; similarly, in fig. 2, b1 is a single tube composed of one IGBT chip, b2 is a single tube composed of a plurality of IGBT chips identical to b1, b1 is connected with collectors c and emitters e of a plurality of b2, and the collectors e are connected in parallel to form a lower tube of a three-phase inverter full bridge. The collector c of the upper tube is connected with the positive input end D1 of the module; the emitter e of the lower tube is connected with the negative input end D2 of the module; the emitter e of the upper tube and the collector c of the lower tube are connected together to form the output H1 in fig. 2, and the output H1 is connected to the outputs H2 and H3.

Fig. 3 is a schematic diagram of a main circuit of the controller based on the IGBT module shown in fig. 2 in a specific application. The direct current power supply output by the vehicle power battery is connected with the input end DC + and DC-of the

motor controller

1, 3 IGBT modules are arranged in the motor controller 1, and the input ends D1 of the 3 IGBT modules are connected together and connected with the DC +; the input ends D2 of the 3 IGBT modules are connected together and connected with DC-; the output ends H2 and H3 of each IGBT module are connected together and connected with one phase winding of the driving motor, and 3 IGBT modules output 3 paths of alternating current U, V and W in total to supply power for the three-phase alternating current driving motor.

Electric vehicles put high demands on the cost of a driving system, and in order to reduce the cost and improve the flexibility of the current grade of a motor controller, a discrete device of an IGBT single tube is used for replacing an IGBT module in the industry, for example, a Model S model of Tesla of American electric vehicle company is used for the motor controller based on parallel connection of the IGBT discrete single tubes. The companies such as internal instole and the like also put forward drive motor controllers based on IGBT discrete single tube parallel connection in batches, as described in the novel patent CN 201710132378-AC motor controller. The IGBT discrete single tube has 3 pins, namely a collector c, an emitter e and a gate g of the IGBT chip in the figure 2 respectively.

The structure and the principle of the motor controller based on the parallel connection of the IGBT discrete single tubes are similar to those of the motor controller based on the IGBT module, the main difference is that the motor controller based on the parallel connection of the IGBT discrete single tubes is formed by connecting a plurality of discrete IGBT single tubes in parallel through an external circuit, and the switching device shown in the figure 1 is formed by connecting IGBT chip single tubes in the IGBT module in parallel inside the module.

In addition, the stator winding of the driving motor of the electric automobile generally adopts a distributed winding, the number of poles of the motor is generally more than 8, for simplifying the description, fig. 4 shows a connection mode of a motor winding with 4 poles and 24 slots, the motor is a commonly-adopted double-layer winding, namely, an upper winding side and a lower winding side are arranged in one stator slot, the upper winding side is represented by a solid line, and the lower winding side is represented by a dotted line. The number of slots of each phase of each pole of the motor is 2, the pitch is 5, wherein the upper layer sides (solid lines) of 1 slot and 2 slots and the lower layer sides (broken lines) of 6 slots and 7 slots are a coil group, 4 similar coil groups are shared by the A phase, the upper layer sides of the other 3 coil groups are respectively positioned in 7 slots and 8 slots, 13 slots and 14 slots, and 19 slots and 20 slots, and the distribution and connection of the 4 coil groups of the A phase winding are shown in fig. 5. Because the pitch is fixed to be 5, each coil can be replaced by an upper layer side for the sake of simplicity, the connection mode of the windings shown in fig. 4 is simplified as shown in fig. 6, and as can be seen from fig. 6, 4 coil groups of each phase of winding are 2 in series and 2 in parallel, namely, the number of parallel branches is 2, and the three-phase windings are in star connection. The 4 coil groups of each phase of winding may also be 4 all in series (for example, fig. 7 shows that the U-phase 4 coil groups are all in series, and the number of parallel branches is 1) or 4 all in parallel (for example, fig. 8 shows that the U-phase 4 coil groups are all in parallel, and the number of parallel branches is 4), which is specifically determined according to the voltage and the height of the driving motor and the design of the motor.

As described above, in the scheme commonly adopted in the current electric vehicle driving system, the main problems of the motor controller + three-phase ac driving motor based on the IGBT module or based on the IGBT discrete single tube parallel connection include:

1. according to the chip parallel scheme of the IGBT module or the IGBT discrete single tube parallel scheme, due to the fact that stray inductance needs to be reduced, the chip and the single tubes need to be closely arranged, heat is concentrated, heat dissipation is relatively difficult, and performance exertion of the IGBT is affected;

2. the motor controller based on the IGBT module has high cost, less current level and poor matching flexibility with a driving motor;

3. because the IGBT current has the positive correlation characteristic with the temperature, the temperature is increased due to the increase of the current, the current is increased due to the increase of the temperature, the overcurrent is easily caused by the parameter difference between the IGBT discrete single tubes, the parallel technology difficulty is large, and the difficulty is increased along with the increase of the number of parallel connection; the number of the IGBT discrete single tubes connected in parallel in the domestic scheme is at most 4, so that the application of the parallel scheme is limited, and the problem of poor reliability also exists.

4. The whole motor controller or the driving motor cannot work due to the fault of one IGBT module of the motor controller or the fault of a part of windings in the driving motor, and the reliability is poor.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model lies in: to the technical problem that prior art exists, the utility model provides an electric automobile actuating system and electric automobile that reliability is high, the flexibility is strong.

In order to solve the technical problem, the utility model provides a technical scheme does:

the utility model provides an electric automobile driving system, includes a plurality of contravariant units and driving motor, a plurality of coils in each phase stator winding of driving motor divide into the multiunit, form the multicomponent winding, each the branch winding is three-phase winding, each branch winding and contravariant unit quantity equal, the three-phase input of a set of branch winding corresponds with the three-phase output of an contravariant unit and links to each other, each the contravariant unit is the three-phase full-bridge structure that constitutes by discrete switching element.

As a further improvement of the above technical solution:

the discrete switch device is an IGBT discrete single tube or a Mosfet discrete single tube or a silicon carbide discrete single tube or a gallium nitride discrete single tube.

And the coils in each phase winding in each sub-winding are mutually connected in series or in parallel.

Each sub-winding is a three-phase polar phase group corresponding to one pole of the driving motor or two three-phase polar phase groups with opposite polarities corresponding to a pair of poles.

Each sub-winding forms a neutral point, and the neutral points of the sub-windings are not connected with each other.

The input ends of the plurality of inversion units are connected in parallel with a bus capacitor, and the bus capacitor comprises a single capacitor or a plurality of capacitors connected in parallel.

The number of the sub-winding or the inversion units is equal to the number of poles or the number of pole pairs of the driving motor.

The utility model also discloses an electric automobile, include as above electric automobile actuating system.

Compared with the prior art, the utility model has the advantages of:

(1) the utility model discloses an electric automobile driving system divides into multiunit branch winding with each phase stator winding of driving motor, and every branch winding pair has a set of independent contravariant unit, and the separate single tube of each contravariant unit can select different current levels for use, realizes more total current levels through the branch winding collocation with different group numbers, and the flexibility is strong; on the other hand, a form of a plurality of sets of main circuits formed by the inverter units and the sub-windings is adopted, the reliability is higher compared with the form of a single set of main circuit formed by the existing single set of inverter and the stator windings, and the main circuits work independently and can be protected redundantly; under the condition that one set of main circuit has a problem, other main circuits can work normally, and the motor driving system can realize power reduction operation, so that the problem that the whole system cannot work after the existing inverter has the problem is solved.

(2) Because the IGBT discrete single tube is adopted to replace the existing IGBT module, the cost of the whole system is reduced;

(3) because the inversion unit is formed by IGBT discrete single tubes, each IGBT discrete single tube can be uniformly distributed in a larger space, the heat dissipation of the IGBT discrete single tubes is facilitated, and the working performance of the IGBT discrete single tubes is better exerted;

(4) because the IGBT discrete single tube is adopted to form the three-phase full-bridge structure, the three-phase full-bridge structure is directly connected with the corresponding sub-winding, the large-capacity bus and the cable which are connected with the motor winding in parallel in the existing IGBT module are omitted, the cost is further reduced, the size and the weight are reduced, the deep integration of the motor and the inversion unit is facilitated, and the size is further reduced.

(5) The utility model discloses an electric automobile has as above electric automobile actuating system's advantage equally.

Drawings

Fig. 1 is a schematic diagram of a main circuit of a drive system in the prior art.

Fig. 2 is a schematic diagram of a main circuit inside an IGBT module in the prior art.

Fig. 3 is a main circuit block diagram of a driving system constructed based on an IGBT module in the prior art.

Fig. 4 is a stator winding arrangement and connection diagram of a driving motor in the prior art.

Fig. 5 is a layout diagram of four coils of a U-phase winding of a driving motor in the prior art.

FIG. 6 is a schematic diagram of the connection of the windings of the driving motor in the prior art (series-parallel connection)

Fig. 7 is a schematic diagram (all connected in series) of connection of windings of a driving motor U in the prior art.

Fig. 8 is a schematic diagram of the connection of the windings of the driving motor U in the prior art (all parallel connection).

Fig. 9 is a schematic diagram of a main circuit according to a first embodiment of the present invention.

Fig. 10 is a schematic diagram of a main circuit according to a second embodiment of the present invention.

The reference numbers in the figures denote: 1. an inversion unit; 101. an IGBT discrete single tube; 2. a drive motor; 3. a stator winding; 4. and (5) dividing the winding.

Detailed Description

The invention is further described with reference to the drawings and the specific embodiments.

As shown in fig. 9 and 10, the electric vehicle driving system of the present embodiment includes a plurality of inverter units 1 and a driving motor 2, wherein a plurality of coils in each phase stator winding 3 of the driving motor 2 are divided into a plurality of groups to form a multi-component winding 4, and each sub-winding 4 is a three-phase winding; the number of the sub-windings 4 is equal to that of the inversion units 1, the three-phase input of one sub-winding 4 is correspondingly connected with the three-phase output of one inversion unit 1, each inversion unit 1 is a three-phase full-bridge structure formed by discrete switching devices, and each sub-winding 4 is a three-phase winding.

The utility model discloses an electric automobile driving system divides each phase stator winding 3 of driving motor 2 into multiunit branch winding 4, and every branch winding 4 corresponds to has a set of independent contravariant unit 1, and the discrete single tube of each contravariant unit 1 can select different current levels for use, realizes more total current levels through the branch winding collocation with different group numbers, and the flexibility is strong; on the other hand, a form of a plurality of sets of main circuits formed by the inverter unit 1 and the sub-windings 4 is adopted, compared with the form of a single set of main circuit formed by the existing single set of inverter and the stator windings 3, the reliability is higher, each set of main circuit can work independently, and the main circuits can be protected redundantly; under the condition that one set of main circuit has a problem, other main circuits can work normally, and the motor driving system can realize power reduction operation, so that the problem that the whole system cannot work after the existing inverter has the problem is solved.

In this embodiment, the discrete switching devices are all IGBT discrete single tubes 101, that is, each set of inverter unit 1 includes six IGBT discrete single tubes 101; the three-phase output of each inversion unit 1 is directly connected with the three-phase input of the corresponding sub-winding 4. In specific application, the grade type of the discrete single IGBT tube 101 is selected according to the conditions of the corresponding shunt winding 4 and the like. Through adopting the three-phase full-bridge structure that the IGBT discrete single tube 101 constitutes, have following technological effect:

(1) because the IGBT discrete single tube 101 is adopted to replace the existing IGBT module, the cost of the whole system is reduced;

(2) because the inverter unit 1 is formed by the IGBT discrete single tubes 101, each IGBT discrete single tube 101 can be uniformly distributed in a larger space, the heat dissipation of the IGBT discrete single tubes 101 is facilitated, and the working performance of the IGBT discrete single tubes 101 can be better exerted;

(3) because the IGBT discrete single tube 101 is adopted to form a three-phase full-bridge structure, the three-phase full-bridge structure is directly connected with the corresponding sub-winding 4, a large-capacity bus and a cable which are connected in parallel and output between the existing IGBT modules are omitted, the cost is further reduced, the deep integration of the driving motor 2 and the inversion unit 1 is facilitated, and the size is reduced.

Of course, in other embodiments, Mosfet discrete single tubes, silicon carbide discrete single tubes, gallium nitride discrete single tubes, or the like may be used instead of IGBT discrete single tubes, and the above technical effects can also be achieved.

In this embodiment, the number of coils in each sub-winding 4 is the same, and the coils in each sub-winding 4 are connected in series; through the arrangement, the structure and the performance of each main circuit are consistent, and the control is convenient. Of course, in other embodiments, the coils in the partial windings 4 may be connected in parallel or in series-parallel (series-parallel).

In this embodiment, the number of the sub-windings or the inverter units is equal to the number of poles or the number of pole pairs of the driving motor; each sub-winding is a three-phase polar phase group corresponding to one pole of the driving motor or two three-phase polar phase groups with opposite polarities corresponding to a pair of poles; each sub-winding forms a neutral point, and the neutral points of the sub-windings are not connected with each other. In addition, a bus capacitor is connected in parallel to the input ends of the multiple inversion units, and the bus capacitor includes a single capacitor (such as the capacitor C in fig. 9 or 10) or multiple capacitors connected in parallel.

The utility model discloses still correspondingly disclose an electric automobile, include as above electric automobile actuating system. The utility model discloses an electric automobile has as above electric automobile actuating system's advantage equally.

The electric vehicle driving system of the present invention is described below with reference to two complete embodiments:

the first embodiment is as follows:

as shown in fig. 9, also explained with the 4-pole 24-slot motor winding shown in fig. 4, the winding in this embodiment is divided into two sets of three-phase sub-windings (F1 and F2 in fig. 9), where the U1 phase of the three-phase sub-winding F1 is a parallel branch of the U-phase winding in fig. 6, i.e., a branch formed by connecting coil groups a1-X1 and coil groups a2-X2 in series; the U2 phase of the three-phase sub-winding F2 is another parallel branch of the U-phase winding in FIG. 6, namely a branch formed by serially connecting coil groups A3-X3 and coil groups A4-X4. Similarly, the V1 phase of the three-phase sub-winding F1 and the V2 phase of the F2 are also formed by disconnecting two parallel branches of the V-phase winding in fig. 6, and similarly, the W1 phase of the sub-winding F1 and the W2 phase of the sub-winding F2 are also formed by two branches of the W-phase winding in fig. 6. The three phases U1, V1 and W1 of the sub-winding F1 are connected to the 3 ac output terminals O11, O13 and O12 of the three-phase inverter bridge E1, respectively.

As shown IN fig. 9, the three-phase inverter bridge E1 is composed of 6 discrete single IGBTs (1-6 # IN fig. 9), collectors c of 3 upper tubes (1#, 3# and 5#) are connected together to form a dc positive electrode IN1+, emitters E of 3 lower tubes (2#, 4# and 6#) are connected together to form a dc negative electrode input IN1-, emitters E of the discrete single IGBTs 1# are connected to collectors c of the discrete single IGBTs 2# to form an ac output terminal O11, emitters E of the discrete single IGBTs 3# are connected to collectors c of the discrete single IGBTs 4# to form an ac output terminal O12, and emitters E of the discrete single IGBTs 5# are connected to collectors c of the discrete single IGBTs 6# to form an ac output terminal O13.

Similarly, three phases U2, V2 and W2 of the sub-winding F2 are connected to three 3 ac output terminals O11, O12 and O13 of the three-phase inverter bridge E2, respectively. The three-phase inverter bridge E2 has the same structure as the E1 and is also composed of 6 IGBT separated single tubes.

As shown in fig. 9, the sub-winding F1 has a neutral point D1, the sub-winding F2 has a neutral point D2, and the neutral point D1 is not connected to the neutral point D2.

Example two:

as shown in fig. 10, the same explanation is given for the 4-pole 24-slot motor winding shown in fig. 4, and each phase winding in this embodiment is divided into four sets of three-phase sub-windings, which are respectively F3-F6 in fig. 10. Similarly, 4 three-phase inverter bridges composed of IGBT discrete single tubes are adopted, namely E3-E6; the three-phase alternating current input ends U1, V1 and W1 of the three-phase sub-winding F3 are respectively connected with the output ends O11, O13 and O12 of a three-phase inverter bridge E3; the three-phase alternating current input ends U2, V2 and W2 of the three-phase sub-winding F4 are respectively connected with the output ends O11, O13 and O12 of a three-phase inverter bridge E4; the three-phase alternating current input ends U3, V3 and W3 of the three-phase sub-winding F5 are respectively connected with the output ends O11, O13 and O12 of a three-phase inverter bridge E5; the three-phase AC input ends U4, V4 and W4 of the three-phase sub-winding F6 are respectively connected with the output ends O11, O13 and O12 of a three-phase inverter bridge E6.

The U1 phase of a three-phase sub-winding F3 of the driving motor 2 is composed of a coil group A1-X1, the V1 phase is composed of a coil group B1-Y1, and the W1 phase is composed of a coil group C1-Z1; the U2 phase of the three-phase sub-winding F4 is composed of a coil group A2-X2, the V2 phase is composed of a coil group B2-Y2, and the W2 phase is composed of a coil group C2-Z2; the U3 phase of the three-phase sub-winding F5 is composed of a coil group A3-X3, the V3 phase is composed of a coil group B3-Y3, and the W3 phase is composed of a coil group C3-Z3; the U4 phase of the three-phase sub-winding F6 is composed of a coil group A4-X4, the V4 phase is composed of a coil group B4-Y4, and the W4 phase is composed of a coil group C4-Z4.

As shown in fig. 10, the sub-winding F3 has a neutral point D3, the sub-winding F4 has a neutral point D4, the sub-winding F5 has a neutral point D5, the sub-winding F6 has a neutral point D6, and the neutral points D3, D4, D5, and D6 are not connected to each other.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention. The technical solution of the present invention can be used by anyone skilled in the art to make many possible variations and modifications, or to modify equivalent embodiments, without departing from the scope of the technical solution of the present invention, using the technical content disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments by the technical entity of the present invention should fall within the protection scope of the technical solution of the present invention.

Claims

1. The utility model provides an electric automobile driving system, its characterized in that includes a plurality of contravariant units (1) and driving motor (2), a plurality of coils in each phase stator winding (3) of driving motor (2) divide into the multiunit, form multiunit winding (4), each divide winding (4) to be three-phase winding, each divide winding (4) and contravariant unit (1) quantity to equal, the three-phase input of a set of branch winding (4) corresponds with the three-phase output of an contravariant unit (1) and links to each other, each contravariant unit (1) are the three-phase full-bridge structure that constitutes by discrete switching element.

2. The electric vehicle drive system of claim 1, wherein the discrete switching devices are IGBT discrete monotubes or Mosfet discrete monotubes or silicon carbide discrete monotubes or gallium nitride discrete monotubes (101).

3. The electric vehicle drive system according to claim 1, wherein the coils in each phase winding of the respective divided windings (4) are connected in series or in parallel with each other.

4. The electric vehicle drive system according to claim 1, 2 or 3, wherein each of the fractional windings (4) is a three-phase polar group corresponding to one pole of the drive motor (2) or two three-phase polar groups with opposite polarities corresponding to a pair of poles.

5. The electric vehicle drive system according to claim 1, 2 or 3, characterized in that each of the partial windings (4) forms a neutral point, and the neutral points of the partial windings (4) are not connected to each other.

6. The electric automobile driving system according to claim 1, 2 or 3, characterized in that a plurality of inverter unit (1) input ends are connected in parallel with a bus capacitor, and the bus capacitor comprises a single capacitor or a plurality of capacitors connected in parallel.

7. The electric vehicle drive system according to claim 1, 2 or 3, characterized in that the number of the partial windings (4) or the inverter units (1) is equal to the number of poles or the number of pole pairs of the drive motor (2).

8. An electric vehicle characterized by comprising the electric vehicle drive system according to any one of claims 1 to 7.