Patent ID: 12199538

DETAILED DESCRIPTION

To make the objectives, technical solutions and advantages of the present disclosure more apparent and clearer, the following describes the present disclosure in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described therein are merely used for explaining the present disclosure instead of limiting the present disclosure.

The following describes implementations of the present disclosure in detail with reference to specific accompanying drawings.

An embodiment of the disclosure provides a motor21. The motor21includes a motor coil211.

Specifically, the motor coil211includes x sets of windings, x≥1, and x is an integer. A number of phases of an xthset of windings is mx. The motor is operated by controlling each set of mx-phase winding by a motor vector controller. In each of the x sets of windings, each phase winding includes nxcoil branches. A first end of each of the nxcoil branches of each phase winding is connected with a first end of a coil branch separated from the coil branch by an electrical angle of 360 degrees, to form mxphase endpoints. A second end of each of the nxcoil branches of each phase winding is further connected with a second end of a coil branch separated from the coil branch by an electrical angle of P*(360*k1+360/mx) degrees, to form nxneutral points, nx≥mx≥2, nx≥3, p=±1, 1≤k1≤(nx−1), and mx, nx, and k1are all integers.

In order to understand a structure of the motor coil211more clearly, the structure of the motor coil211is described below by using x being 1, mxbeing 3, and nxbeing 4 as an example.

FIG.1is a schematic diagram of a circuit structure of the motor coil211when x is 1, mxis 3, and nxis 4 according to this embodiment.

Specifically, referring toFIG.1, the motor coil211includes one set of windings. The set of windings include three phase windings: a first phase winding A, a second phase winding B, and a third phase winding C. Each phase winding includes four coil branches. First ends (which are respectively A1, A2, A3, and A4) of the coil branches in the first phase winding A are connected together to form a first phase endpoint. First ends (which are respectively B1, B2, B3, and B4) of the coil branches in the second phase winding B are connected together to form a second phase endpoint. First ends (which are respectively C1, C2, C3, and C4) of the coil branches in the third phase winding C are connected together to form a third phase endpoint.

Further, a second end of each of the four coil branches of each phase winding is connected with a second end of a coil branch separated from the coil branch by an electrical angle of 480 degrees to form four neutral points. In this case, P is 1, and k1is 1. Specifically, referring toFIG.1, a second end a1of a first coil branch of the first phase winding A, a second end b2of a second coil branch of the second phase winding B, and a second end c3of a third coil branch of the third phase winding are connected together to form a first neutral point N1. A second end a2of a second coil branch of the first phase winding A, a second end b3of a third coil branch of the second phase winding B, and a second end c4of a fourth coil branch of the third phase winding C are connected together to form a second neutral point N2. A second end c1of a first coil branch of the third phase winding C, a second end a3of a third coil branch of the first phase winding A, and a second end b4of a fourth coil branch of the second phase winding B are connected together to form a third neutral point N3. A second end b1of a first coil branch of the second phase winding B, a second end c2of a second coil branch of the third phase winding C, and a second end a4of a fourth coil branch of the first phase winding A are connected together to form a fourth neutral point N4.

Specifically, when a current passes through the motor coil211, any two coil branches of a first coil branch of a first phase coil A, a first coil branch of a second phase coil B, and a first coil branch of a third phase coil C are spatially spaced apart to form two overlapping circuits, and a mutual inductance effect is generated between the two coil branches by using the overlapping circuits.

In this embodiment, by means of staggered winding in the motor coil211, the mutual inductance effect generated when the current passes through the motor coil211can be effectively reduced. Therefore, the equivalent inductance can be increased, so that the inductance of the motor coil211is increased. In this way, the control of the current ripples is enhanced, and the energy loss of the motor coil is reduced, thereby resolving the problem of the large energy loss and the impedance in the control of the current ripples of the motor coil in the related art.

Further, as an implementation of the disclosure, in each set of windings, projections of the first end of each of the nxcoil branches of each phase winding and the first end of the coil branch separated from the coil branch by the electrical angle of 360 degrees on an end portion of the motor21are arranged in a circle. The first end and the second end of each coil branch are opposite to each other in an axial direction of the motor21.

In order to understand the structure of the motor coil211more clearly, the motor coil211shown inFIG.1is used as an example. In this case, a front-side structure of the one set of windings is shown inFIG.2, and a back-side structure of the set of windings is shown inFIG.3.

As shown inFIG.2andFIG.3, projections of the first end of each of the four coil branches of each coil and the first end of the coil branch separated from the coil branch by the electrical angle of 360 degrees on the end portion of the motor21are arranged in a circle.

The first end and the second end of each coil branch are opposite to each other in the axial direction of the motor21.

In this embodiment, by arranging the projections of the first end of each of the nxcoil branches of each phase winding and the first end of the coil branch separated from the coil branch by the electrical angle of 360 degrees on the end portion of the motor21in a circle, an occupied area of the motor coil can be effectively reduced, and a space utilization for the motor coil211in the motor21can be increased.

Further, as an implementation of the disclosure, when a number mxof phases of each set of windings is equal, projections of second ends of

∑i=1x⁢(mx*nx)
coil branches on the end portion of the motor are cyclically arranged in a circle from a 1stphase to an mxthphase. Electrical angles of two coil branches in one phase winding arranged adjacent to each other differ by 360 degrees. Electrical angles of two adjacent coil branches in nxcoil branches within a same cycle differ by 360/mxdegrees.

Cyclic arrangement into a circle from the 1stphase to the mxthphase means that all phase coil branches are arranged from the 1stphase to the mxthphase in ascending order, and the operation is cyclically repeated from the 1stphase to the mxthphase. An arrangement direction of each cycle on the circle is clockwise or counterclockwise.

In order to understand the content of this implementation more clearly, the motor coil211shown inFIG.1is used as an example. In this case, a projection of the end portion of the motor is shown inFIG.4.

As shown inFIG.4, projections of second ends of 12 coil branches on the end portion of the motor are cyclically arranged in a circle according from the first phase winding A to the third phase winding C. Electrical angles of the two coil branches in one phase winding arranged adjacent to each other differ by 360 degrees. Electrical angles of two adjacent coil branches in four coil branches within a same cycle differs by 90 degrees.

It is to be noted that, the cycle herein is specifically composed of a coil branch in each phase winding, and a sequence is an arrangement direction of the projections of all phase windings on the end portion. For example, in the motor coil211shown inFIG.1, a cycle is composed of a coil branch in each phase winding, and four cycles are formed. The arrangement direction of all phase windings is A, B, and C in a clockwise direction. The arrangement direction of all phase windings are C, B, and A in a counterclockwise direction. One cycle in the motor coil211is a4, b4, and c4. The clockwise arrangement sequence is a4, b4, and c4. The counterclockwise arrangement sequence is c4, b4, and a4.

As a preferred solution of this embodiment, a coil branch corresponding to an mxthphase of one of the cycles is not connected with a coil branch corresponding to a first phase of a next cycle, a coil branch corresponding to a first phase of one of the cycles is not connected with a coil branch corresponding to an mxthphase of a last cycle, and a coil branch corresponding to a first phase of a first cycle is not connected with a coil branch corresponding to an mxthphase of a

∑i=1X⁢nxth
cycle.

In this embodiment, when the number mxof phases of each set of windings is equal, the projections of the second ends of the

∑i=1x⁢(mx*nx)
coil branches in the motor coil211on the end portion of the motor are cyclically arranged in a circle from the 1stphase to the mxthphase, the electrical angles of the two coil branches in one phase winding arranged adjacent to each other differ by 360 degrees, and the electrical angles of the two adjacent coil branches in the nxcoil branches within a same cycle differ by 360/mxdegrees. In this way, when the current passes through the motor coil211, the energy losses can be reduced, and the control of the current ripples is enhanced.

An embodiment of the disclosure provides a motor22. The motor22includes a motor coil221.

Specifically, the motor22includes the motor coil221. The motor coil221includes x sets of windings, x≥1, and x is an integer. A number of phases of each of the x sets of windings is m. The x sets of windings include x*m phase windings. The motor is operated by controlling each set of m-phase winding by a motor vector controller. In the x*m phase windings, each phase winding includes n coil branches. Each of the n coil branches of each phase winding is connected with a coil branch separated from the coil branch by an electrical angle of 360 degrees to form x*m phase endpoints. Each of the n coil branches of each phase winding is further connected with a coil branch separated from the coil branch by an electrical angle of P*(360*k2+360/(x*m)) degrees to form n neutral points, n≥x*m, m≥2, n≥3, p=±1, 1≤k2≤(n−1), and m, n, and k2are all integers.

In order to understand the structure of the motor coil221more clearly, the structure of the motor coil221is described below by using x being 1, mxbeing 6, and nxbeing 7 as an example.

FIG.5is a schematic diagram of a circuit structure of the motor coil221when x is 1, m is 6, and n is 7 according to this embodiment.

Specifically, referring toFIG.5, the motor coil221includes one set of windings. The set of windings include six phase windings: a first phase winding A, a second phase winding B, a third phase winding C, a fourth phase winding D, a fifth phase winding E, and a sixth phase winding F. Each phase winding includes seven coil branches. First ends (which are respectively A1, A2, A3, A4, A5, A6, and A7) of all of the coil branches in the first phase winding A are connected together to form a first phase endpoint. First ends (which are respectively B1, B2, B3, B4, B5, B6, and B7) of the coil branches in the second phase winding B are connected together to form a second phase endpoint. First ends (which are respectively C1, C2, C3, C4, C5, C6, and C7) of the coil branches in the third phase winding C are connected together to form a third phase endpoint. First ends (which are respectively D1, D2, D3, D4, D5, D6, and D7) of the coil branches in the fourth phase winding U are connected together to form a fourth phase endpoint. First ends (which are respectively E1, E2, E3, E4, E5, E6, and E7) of the coil branches in the fifth phase winding V are connected together to form a fifth phase endpoint. First ends (which are respectively F1, F2, F3, F4, F5, F6, and F7) of the coil branches in the sixth phase winding W are connected together to form a sixth phase endpoint.

Further, a second end of each of the seven coil branches of each phase winding is connected with a second end of a coil branch separated from the coil branch by an electrical angle of 420 degrees to form four neutral points. In this case, P is 1, and k2is 1. Specifically, referring toFIG.5,FIG.5does not show a method for connecting neutral points N formed by the second ends of all of the coil branches in each phase winding. The method specifically includes the following: A second end a1of a first coil branch of the first phase winding A, a second end b2of a second coil branch of the second phase winding B, a second end c3of a third coil branch of the third phase winding C, a second end d4of a fourth coil branch of the fourth phase winding D, a second end e5of a fifth coil branch of a fifth phase winding E, and a second end f6of a sixth coil branch of the sixth phase winding F are connected together to form a first neutral point N1. A second end a2of a second coil branch of the first phase winding A, a second end b3of a third coil branch of the second phase winding B, a second end c4of a fourth coil branch of the third phase winding C, a second end d5of a fifth coil branch of the fourth phase winding D, a second end e6of a sixth coil branch of the fifth phase winding E, and a second end f7of a seventh coil branch of the sixth phase winding F are connected together to form a second neutral point N2. A second end a3of a third coil branch of the first phase winding A, a second end b4of a fourth coil branch of the second phase winding B, a second end c5of a fifth coil branch of the third phase winding C, a second end d6of a sixth coil branch of the fourth phase winding D, a second end e7of a seventh coil branch of the fifth phase winding E, and a second end f1of a first coil branch of the sixth phase winding F are connected together to form a third neutral point N3. A second end a4of a fourth coil branch of the first phase winding A, a second end b5of a fifth coil branch of the second phase winding B, a second end c6of a sixth coil branch of the third phase winding C, a second end d7of a seventh coil branch of the fourth phase winding D, a second end e1of a first coil branch of the fifth phase winding E, and a second end f2of a second coil branch of the sixth phase winding F are connected together to form a fourth neutral point N4. A second end a5of a fifth coil branch of the first phase winding A, a second end b6of a sixth coil branch of the second phase winding B, a second end c7of a seventh coil branch of the third phase winding C, a second end d1of a first coil branch of the fourth phase winding D, a second end e2of a second coil branch of the fifth phase winding E, and a second end f3of a third coil branch of the sixth phase winding F are connected together to form a fifth neutral point N5. A second end a6of a sixth coil branch of the first phase winding A, a second end b7of a seventh coil branch of the second phase winding B, a second end c1of a first coil branch of the third phase winding C, a second end d2of a second coil branch of the fourth phase winding D, a second end e3of a third coil branch of the fifth phase winding E, and a second end f4of a fourth coil branch of the sixth phase winding F are connected together to form a sixth neutral point N6. A second end a7of a seventh coil branch of the first phase winding A, a second end b1of a first coil branch of the second phase winding B, a second end c2of a second coil branch of the third phase winding C, a second end d3of a third coil branch of the fourth phase winding D, a second end e4of a fourth coil branch of the fifth phase winding E, and a second end f5of a fifth coil branch of the sixth phase winding F are connected together to form a seventh neutral point N7.

In this embodiment, by means of staggered winding in the motor coil221, the mutual inductance effect generated when the current passes through the motor coil221can be effectively reduced. Therefore, equivalent inductance can be increased, so that the inductance of the motor coil221is increased. In this way, the control of the current ripples is enhanced, and the energy losses of the motor coil are reduced, thereby resolving the problem of large energy losses and the impedance in the control of the current ripples of the motor coil in the related art.

Further, as an implementation of the disclosure, a phase line of one set of windings is staggered from a phase line of another set of windings, a second end of a coil branch of the set of windings is connected with a second end of a coil branch separated by an electrical angle of P*(360*k2+360/(x*m)) degrees in the another set of windings, to form n neutral points.

In order to understand the content of this implementation more clearly, a structure of the motor coil211is described below by using x being 2, mxbeing 3, and nxbeing 3 as an example.

FIG.9is a schematic diagram of a circuit structure of the motor coil221when x is 2, m is 3, and n is 3 according to this embodiment.

Specifically, referring toFIG.9, the motor coil221includes a first set of windings2211and a second set of windings2212. Each set of windings include three phase windings. The three phase windings of the first set of windings are respectively a first phase winding A, a second phase winding B, and a third phase winding C. The three phase windings of the second set of windings are respectively a fourth phase winding U, a fifth phase winding V, and a sixth phase winding W. Each phase winding includes three coil branches. First ends (which are respectively A1, A2, and A3) of all of the coil branches in the first phase winding A are connected together to form a first phase endpoint. First ends (which are respectively B1, B2, and B3) of all of the coil branches in the second phase winding B are connected together to form a second phase endpoint. First ends (which are respectively C1, C2, and C3) of all of the coil branches in the third phase winding C are connected together to form a third phase endpoint. First ends (which are respectively U1, U2, and U3) of all of the coil branches in the fourth phase winding U are connected together to form a fourth phase endpoint. First ends (which are respectively V1, V2, and V3) of all of the coil branches in the fifth phase winding V are connected together to form a fifth phase endpoint. First ends (which are respectively W1, W2, and W3) of all of the coil branches in the sixth phase winding W are connected together to form a sixth phase endpoint.

Further, a second end of each of the three coil branches of each phase winding is connected with a second end of a coil branch separated from the coil branch by an electrical angle of 420 degrees, to form three neutral points. In this case, P is 1, and k2is 1. For details of a connection method for forming three neutral points, refer toFIG.9.

In this embodiment, by means of winding in another staggering manner, the mutual inductance effect generated when the current passes through the motor coil221can be effectively reduced. Therefore, equivalent inductance can be increased, so that the inductance of the motor coil221is increased. In this way, the control of the current ripples is enhanced, and the energy losses of the motor coil are reduced, thereby resolving the problem of large energy losses and the impedance in the control of the current ripples of the motor coil in the related art.

Further, as an implementation of the disclosure, projections of a first end of each of the n coil branches of each phase winding and a first end of a coil branch separated from the coil branch by an electrical angle of 360 degrees on the end portion of the motor are arranged in a circle. The first end and the second end of each coil branch are opposite to each other in an axial direction of the motor.

The motor coil221for which x is 1, m is 6, and n is 7 is used as an example. As shown inFIG.6andFIG.7, projections of a first end of each of the n coil branches and a first end of a coil branch separated from the coil branch by an electrical angle of 360 degrees on an end portion of the motor are arranged in a circle.

In this embodiment, by arranging the projections of the first end of each of the nxcoil branches of each phase winding and the first end of the coil branch separated from the coil branch by the electrical angle of 360 degrees on the end portion of the motor22in a circle, an occupied area of the motor coil can be effectively reduced, and a space utilization for the motor coil221in the motor22can be increased.

Further, as an implementation of the disclosure, projections of second ends of m*n coil branches on the end portion of the motor are cyclically arranged in a circle from a 1stphase to an (x*m)*thphase, electrical angles of two coil branches in one phase winding arranged adjacent to each other differ by 360 degrees, and electrical angles of two adjacent coil branches in x*m coil branches within a same cycle differ by 360/(x*m) degrees.

The motor coil221for which x is 1, m is 6, and n is 7 is as an example. As shown inFIG.8, projections of second ends of m*n coil branches on the end portion of the motor are cyclically arranged in a circle from a 1stphase to an (x*m)thphase.

In this embodiment, projections of second ends of m*n coil branches on the end portion of the motor are cyclically arranged in a circle from a 1st phase to an (x*m)th phase, electrical angles of two coil branches in one phase winding arranged adjacent to each other differ by 360 degrees, and electrical angles of two adjacent coil branches in nxcoil branches within a same cycle differ by 360/(x*m) degrees. In this way, when the current passes through the motor coil221, the energy losses can be reduced, and the control of the current ripples is enhanced.

As shown inFIG.10, the disclosure further provides an energy conversion device4. The energy conversion device4includes a motor2and a reversible pulse-width modulation (PWM) rectifier41.

Specifically, the reversible PWM rectifier41is connected with the motor2. A charging circuit or a discharging circuit is formed by an external charging port or a discharging port5and an external battery6by using the energy conversion device4. A driving circuit is formed by the external battery6and the energy conversion device4. The motor2and the reversible PWM rectifier41are both connected with the external charging port or the discharging port5. The reversible PWM rectifier41is connected with the external battery6.

In the above driving circuit, the reversible PWM rectifier41is configured to convert a direct current (DC) inputted by the battery6into an alternating current (AC), to drive the motor2to operate. In the above charging circuit, the reversible PWM rectifier41is configured to boost the DC in cooperation with the motor2and output the boosted DC, so as to charge the battery. In the above discharging circuit, the reversible PWM rectifier41causes the DC inputted by the battery6to be discharged through the discharging port5.

In the above driving circuit, the motor2is configured to receive the AC inputted by the reversible PWM rectifier41, to achieve driving. In the above charging circuit, the motor2is configured to boost the DC in cooperation with the reversible PWM rectifier41. In the above charging circuit, the motor2causes the DC inputted by the battery6to be discharged through the discharging port5.

It is to be noted that, the motor2may be the motor21, or may be the motor22. The motor2includes a motor coil. The motor coil may be the motor coil211, or may be the motor coil221. No specific limitation is imposed herein.

In this embodiment, by means of the motor2and the reversible PWM rectifier41, the boosting of the DC can be realized in the charging circuit, and by means of the battery6and the reversible PWM rectifier41, the driving of the motor2can be achieved. Therefore, the motor2and the reversible PWM rectifier41are reused. In this way, the circuit integration level is enhanced, the circuit structure is simplified, thereby reducing the size and the costs.

Further, as an implementation of the disclosure, the reversible PWM rectifier41includes K groups of Mxbridge arms. A midpoint of at least one bridge arm in a group of Mxbridge arms is connected with a phase endpoint. Any two phase endpoints are connected with different bridge arms. A first end and a second end of each bridge arm in the K groups of Mxbridge arms are connected together to form a first bus terminal and a second bus terminal, Mx≥mx, Mx≥m, K≥x, and K and Mxare both integers. The external charging port or the discharging port5is connected with a neutral line led out from a neutral point of the motor and the second bus terminal. The first bus terminal is connected with a positive electrode of the battery6, and the second bus terminal is connected with a negative electrode of the battery6.

In order to understand the content of this embodiment more clearly, K being 1 and Mxbeing 3 is used as an example.

Specifically, as shown inFIG.11, the reversible PWM rectifier41includes a group of three bridge arms. Each bridge arm includes two power switches connected in series. The motor2includes three phase windings. Each phase winding includes four coil branches and forms three phase endpoints: A, B, and C. The three phase endpoints are connected with midpoints of the three bridge arms in a one-to-one correspondence. First ends of all of the bridge arms are connected together to form the first bus terminal, and then connected with the positive electrode of the battery6. Second terminals of all of the bridge arms are connected together to form the second bus terminal, and then connected with the negative electrode of the battery6.

In the above embodiment, when the battery6outputs a DC, a bridge arm in the reversible PWM rectifier41converts the DC into an AC and inputs the AC to one phase winding, so as to drive the motor2to operate. Other two phase windings output an AC, and the two bridge arms connected with the other two phase windings convert the AC into a DC, and return the DC to the battery6.

In the above embodiment, when the charging port or the discharging port5inputs a DC, a power switch VT4is controlled to turn on and a power switch VT1to turn off, so that an energy storage circuit is formed by the charging port or the discharging port5, the first phase winding A, and the power switch VT4, and the first phase winding A completes energy storage. When the power switch VT4is turned off, and the power switch VT1is turned on, an energy releasing circuit is formed by the charging port or the discharging port5, the first phase winding A, the power switch VT1, and the battery6. The power switch VT1outputs the boosted DC to charge the battery6.

It is to be noted that, a manner in which a power switch VT3and a power switch VT5output a DC is same as the manner in which the power switch VT4outputs the boosted DC, which is not described herein.

In addition, when the battery6outputs the DC, the reversible PWM rectifier41and the motor2cause the DC to be discharged through the charging port or the discharging port5. The discharging process is opposite to the above charging process, which is not described herein.

In this embodiment, by means of the reversible PWM rectifier41and the motor2in cooperation, the DC outputted by the charging port or the discharging port5is converted into the boosted DC for charging the battery6. In addition, when the external battery6outputs the DC, the DC is converted by the reversible PWM rectifier41into an AC to drive the motor2. Discharging may be further achieved by the motor2and the reversible PWM rectifier41. Therefore, the reuse of the reversible PWM rectifier41and the motor2in the driving circuit and the charging and discharging circuits is realized. In this way, the circuit integration level is enhanced, and the circuit structure is simplified, thereby reducing the size and the costs.

Further, as an implementation of the disclosure, at least one neutral line is led out from one of the neutral points of each set of windings.

Specifically, the neutral line may be a neutral line led out from one or more neutral points that are connected together, or may be a plurality of neutral lines correspondingly led out from a plurality of neutral points one by one.

Further, a number of connected neutral points is controlled by using the neutral line, to control the inductance formed by the motor coil in the motor2. In this way, in different charging and discharging conditions, different numbers of neutral points are connected, to satisfy different charging power requirements.

In this embodiment, by leading out different numbers of neutral lines, the inductance formed by the motor coil in the motor2can be controlled, so that the power requirements in different circuit conditions can be satisfied.

Further, as an implementation of the disclosure, as shown inFIG.12, the charging port5is a DC charging port51.

Specifically, one end of the DC charging port51is connected with the neutral line, and another end of the DC charging port51is connected with the second bus terminal of the reversible PWM rectifier41.

In this embodiment, a DC charging circuit for charging the battery6or a DC discharging circuit is formed by the DC charging port51, the motor coil, and the reversible PWM rectifier41. The DC charging circuit and the DC discharging circuit have been described above, and therefore are not described herein again.

In this embodiment, by means of the reversible PWM rectifier41and the motor2in cooperation, the DC outputted by the DC charging port51is converted into the boosted DC for charging the battery6. In addition, when the external battery6outputs the DC, the DC is converted by the reversible PWM rectifier41into an AC to drive the motor2. Discharging may be further achieved by the motor2and the reversible PWM rectifier41. Therefore, the reuse of the reversible PWM rectifier41and the motor2in the driving circuit and the charging and discharging circuits is realized. In this way, the circuit integration level is enhanced, and the circuit structure is simplified, thereby reducing the size and the costs.

Further, as an implementation of the disclosure, as shown inFIG.13, the energy conversion device4further includes a two-way bridge arm42.

Specifically, the charging port or the discharging port5includes an AC discharging port52. One end of the AC discharging port52is connected with the motor2by the neutral line. The two-way bridge arm42is connected between the first bus terminal of the reversible PWM rectifier41and the second bus terminal of the reversible PWM rectifier41. Another end of the AC discharging port52is connected with a midpoint of the two-way bridge arm42.

The two-way bridge arm42includes a power switch VT7and a power switch VT8connected in series. A midpoint between the power switch VT7and the power switch VT8is used as the midpoint of the two-way bridge arm42.

In this embodiment, the AC charging port52inputs an AC. The three bridge arms in the reversible PWM rectifier respectively form rectifier full bridges with the two-way bridge arm42, and convert the AC inputted by the AC charging port52into a DC. The AC charging port cooperates with the motor coil, so that the motor coil can implement the energy storage and energy releasing processes. The boosted DC is outputted by the three bridge arms in the reversible PWM rectifier and the two-way bridge arm42.

In addition, by means of the two-way bridge arm42, the reversible PWM rectifier, and the motor2, AC discharging is performed through the AC charging port on the DC outputted by the battery6.

In this embodiment, by means of the energy conversion device4including the two-way bridge arm42, AC charging and AC discharging can be achieved by using the energy conversion device4, and the motor2can be driven. In this way, the circuit integration level is enhanced, and the circuit structure is simplified, thereby reducing the size and the costs.

Further, as an implementation of the disclosure, as shown inFIG.14, the charging port or the discharging port5includes a DC charging port51and an AC discharging port52. The energy conversion device4includes a two-way bridge arm42.

Specifically, one end of the DC charging port51is connected with the neutral line, and another end of the DC charging port51is connected with the second bus terminal of the reversible PWM rectifier41. One end of the AC discharging port52is connected with the motor2by the neutral line. The two-way bridge arm42is connected between the first bus terminal of the reversible PWM rectifier41and the second bus terminal of the reversible PWM rectifier41. Another end of the AC discharging port52is connected with a midpoint of the two-way bridge arm42.

The two-way bridge arm42includes a power switch VT7and a power switch VT8connected in series. A midpoint between the power switch VT7and the power switch VT8is used as the midpoint of the two-way bridge arm42.

In this embodiment, the AC charging port52inputs an AC. The three bridge arms in the reversible PWM rectifier respectively form rectifier full bridges with the two-way bridge arm41, and convert the AC inputted by the AC charging port52into a DC. The AC charging port cooperates with the motor coil, so that the motor coil can implement the energy storage and energy releasing processes. The boosted DC is outputted by the three bridge arms in the reversible PWM rectifier and the two-way bridge arm42. A DC charging circuit for charging the battery6or a DC discharging circuit is formed by the DC charging port51, the motor coil, and the reversible PWM rectifier41. The DC charging circuit and the DC discharging circuit have been described above, and therefore are not described herein again.

In this embodiment, by means of the reversible PWM rectifier41and the motor2in cooperation, the DC outputted by the DC charging port51is converted into the boosted DC for charging the battery6, and AC charging and AC discharging can be achieved by using the energy conversion device4. In addition, when the external battery6outputs the DC, the DC is converted by the reversible PWM rectifier41into an AC to drive the motor2. Discharging may be further achieved by the motor2and the reversible PWM rectifier41. Therefore, the reuse of the reversible PWM rectifier41and the motor2in the driving circuit, the AC the charging and discharging circuits, and the DC charging and discharging circuits is realized. In this way, the circuit integration level is enhanced, and the circuit structure is simplified, thereby reducing the size and the costs. In addition, in the disclosure, a number of connected neutral points may be controlled to control the inductance of the motor coil, so as to satisfy different charging power requirements.

The foregoing descriptions are merely preferred embodiments of the present disclosure, but are not intended to limit the present disclosure. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present disclosure shall fall within the protection scope of the present disclosure.