CN112550062A

CN112550062A - Cooperative control method and device for energy conversion device, storage medium and vehicle

Info

Publication number: CN112550062A
Application number: CN201910912735.4A
Authority: CN
Inventors: 凌和平; 潘华; 李吉成; 张宇昕; 贝明
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2019-09-25
Filing date: 2019-09-25
Publication date: 2021-03-26
Anticipated expiration: 2039-09-25
Also published as: CN112550062B

Abstract

The application provides a cooperative control method and device of an energy conversion device, a storage medium and a vehicle, wherein the cooperative control method comprises the following steps: the method comprises the steps of obtaining first heating power according to target charging and discharging power, obtaining first quadrature axis current and first direct axis current according to target driving power, obtaining target quadrature axis current and target direct axis current according to the relation between the first heating power and the target heating power, calculating the duty ratio of each phase of bridge arm in a PWM rectifier according to the target quadrature axis current, the target direct axis current, the target charging and discharging current, the sampling current value on each phase of coil and the position of a motor rotor, calculating the duty ratio of the bridge arm in a power switch module according to the target charging and discharging current and the sampling value of the charging and discharging current, controlling the PWM rectifier and the power switch module according to the duty ratio, enabling current output by an external battery or power supply device to flow through the motor coil to generate heat, and simultaneously achieving cooperative work of the charging and discharging process, the heating process and the torque output.

Description

Cooperative control method and device for energy conversion device, storage medium and vehicle

Technical Field

The present disclosure relates to the field of vehicle technologies, and in particular, to a cooperative control method and apparatus for an energy conversion apparatus, a storage medium, and a vehicle.

Background

With the continuous popularization of electric vehicles, more and more electric vehicles enter the society and families, bringing great convenience for people to go out, and the power battery in the electric vehicle is usually a lithium ion battery, the general working temperature of the lithium ion battery is-20 ℃ to 55 ℃, and the lithium ion battery is not allowed to be charged at a low temperature. In the prior art, a scheme for heating a low-temperature battery is to heat coolant of a battery cooling loop by using a PTC heater or an electric heating wire heater or an engine or a motor at a low temperature, and heat a battery cell to a predetermined temperature by using the coolant. And when the battery is in a low-temperature and low-power state, such as an extreme condition of-19 ℃, the SOC is 0, the battery is not allowed to discharge, only low-current charging is allowed, high-power heating and low-power charging, even 0-power heating, 0-power charging and starting are performed, the PTC heater is hard to be sufficient, and heating while charging is impossible, so that the battery charging time is long.

In summary, the prior art has problems that the cost is increased when the power battery is heated by the heating device at a low temperature, and two or three of the charging and discharging process, the heating process and the torque output process cannot work cooperatively.

Disclosure of Invention

The application aims to provide a cooperative control method and device for an energy conversion device, a storage medium and a vehicle, which can solve the problems that the cost is increased when a heating device is adopted to heat a power battery in a low-temperature state, and two or three of a charging and discharging process, a heating process and a torque output process cannot work cooperatively.

The present application is implemented as such, in a first aspect, a cooperative control method for an energy conversion device is provided, where the energy conversion device includes a reversible PWM rectifier, a motor coil, a power switch module, and an inductor, the reversible PWM rectifier is connected to the motor coil, a positive terminal of an external battery is connected to a first bus terminal of the reversible PWM rectifier and a first terminal of the power switch module, a negative terminal of the external battery is connected to a second bus terminal of the reversible PWM rectifier and a second terminal of the power switch module, a third terminal of the power switch module is connected to the first terminal of the inductor, and a first terminal and a second terminal of an external charge and discharge port are respectively connected to the second terminal of the inductor and the second terminal of the power switch module;

the cooperative control method comprises the following steps:

acquiring target heating power, target charge-discharge power and target driving power;

acquiring target charging and discharging current output by the external charging and discharging port according to target charging and discharging power, acquiring first quadrature axis current and first direct axis current in a synchronous rotation coordinate system based on motor rotor magnetic field orientation according to the target driving power, and acquiring first heating power of the motor coil according to the first quadrature axis current and the first direct axis current;

when the deviation between the first heating power and the target heating power is not in a preset range, adjusting the first quadrature-axis current and the first direct-axis current to a target quadrature-axis current and a target direct-axis current according to the target driving power, so that the deviation between the first heating power and the target heating power is in the preset range;

and acquiring a sampling current value, a charging and discharging current sampling value and a motor rotor position on each phase of coil, calculating the duty ratio of each phase of bridge arm in the reversible PWM rectifier according to a target quadrature axis current, a target direct axis current, the sampling current value on each phase of coil and the motor rotor position, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the charging and discharging current sampling value.

A second aspect of the application provides a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, performs the steps of the method of the first aspect.

A third aspect of the present application provides a cooperative control apparatus for an energy conversion apparatus, where the energy conversion apparatus includes a reversible PWM rectifier, a motor coil, a power switch module, and an inductor, the reversible PWM rectifier is connected to the motor coil, a positive terminal of an external battery is connected to a first bus terminal of the reversible PWM rectifier and a first terminal of the power switch module, a negative terminal of the external battery is connected to a second bus terminal of the reversible PWM rectifier and a second terminal of the power switch module, a third terminal of the power switch module is connected to a first terminal of the inductor, and a first terminal and a second terminal of an external charge/discharge port are respectively connected to a second terminal of the inductor and a second terminal of the power switch module;

the cooperative control apparatus includes:

the power acquisition module is used for acquiring target heating power, target charging and discharging power and target driving power;

the first heating power calculation module is used for acquiring target charging and discharging current output by the external charging and discharging port according to target charging and discharging power, acquiring first quadrature axis current and first direct axis current in a synchronous rotation coordinate system based on motor rotor magnetic field orientation according to the target driving power, and acquiring first heating power of the motor coil according to the first quadrature axis current and the first direct axis current; when the deviation between the first heating power and the target heating power is not within a preset range, adjusting the first quadrature-axis current and the first direct-axis current to a target quadrature-axis current and a target direct-axis current according to the target driving power, and enabling the deviation between the first heating power and the target heating power to be within the preset range; and the duty ratio acquisition module is used for acquiring a sampling current value, a charging and discharging current sampling value and a rotor electrical angle of each phase of coil, calculating the duty ratio of each phase of bridge arm in the reversible PWM rectifier according to a target quadrature axis current, a target direct axis current, a target charging and discharging current, the sampling current value of each phase of coil and a motor rotor electrical angle, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the charging and discharging current sampling value.

A fourth aspect of the present application provides a vehicle further including a cooperative control device of the energy conversion device of the third aspect.

The application provides a cooperative control method and device of an energy conversion device, a storage medium and a vehicle, and has the technical effects that: by adopting an energy conversion device comprising a reversible PWM rectifier and a motor coil, the energy conversion device is connected with an external battery and is connected with power supply equipment or electric equipment through a charge-discharge port, target heating power, target driving power and target charge-discharge power are obtained, target charge-discharge current output by the external charge-discharge port is obtained according to the target charge-discharge power, first quadrature axis current and first direct axis current are obtained according to the target driving power, first heating power of the motor coil is obtained according to the first quadrature axis current and the first direct axis current, the first quadrature axis current and the first direct axis current are regulated according to the relation between the first heating power and the target heating power to obtain target quadrature axis current and target direct axis current, and the duty ratio of each phase bridge arm in the PWM rectifier is calculated according to the target quadrature axis current, the target direct axis current, the target charge-discharge current, the sampling current value on each phase coil and the position of a motor rotor, and calculating the duty ratio of a bridge arm in the power switch module according to the target charging and discharging current and the sampling value of the charging and discharging current, controlling the on and off of a switch device on each phase of the bridge arm in the PWM rectifier and a switch device on the bridge arm in the power switch module according to the duty ratio, so that the current output by an external battery or power supply equipment flows through a motor coil to generate heat so as to heat cooling liquid flowing through a cooling pipe of the motor coil, and when the cooling liquid flows through a power battery, the power battery is heated, an additional power battery heating device can be omitted, the cost of the whole device is reduced, the charging and discharging of the battery in a low-temperature state are ensured, and the cooperative work of the two or three in the charging and discharging process, the heating process and the torque output process is.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of an energy conversion device according to an embodiment of the present disclosure;

fig. 2 is a flowchart of a cooperative control method for an energy conversion device according to an embodiment of the present disclosure;

fig. 3 is a flowchart of step S20 in the cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 4 is a three-dimensional space transformation diagram in a cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 5 is a coordinate transformation diagram in a cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

FIG. 6 is a torque graph illustrating a cooperative control method for an energy conversion apparatus according to an embodiment of the present disclosure;

fig. 7 is a flowchart of step S50 in the cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 8 is a flowchart of step S501 in a cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 9 is a flowchart of step S502 in a cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 10 is another flowchart of step S502 in a cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 11 is a flowchart of step S50 in the cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 12 is a flowchart of step S50 in the cooperative control method of an energy conversion apparatus according to an embodiment of the present application;

fig. 13 is a flowchart of a cooperative control method for an energy conversion apparatus according to a second embodiment of the present application;

fig. 14 is a flowchart of a cooperative control method for an energy conversion apparatus according to a third embodiment of the present application;

fig. 15 is a flowchart of a cooperative control method of an energy conversion apparatus according to a fourth embodiment of the present application;

fig. 16 is a vector control diagram of a cooperative control method of an energy conversion device according to an embodiment of the present application;

fig. 17 is another vector control diagram of a cooperative control method of an energy conversion device according to an embodiment of the present application;

fig. 18 is a circuit diagram of an energy conversion device according to an embodiment of the present application;

fig. 19 is another circuit diagram of an energy conversion device according to an embodiment of the present application;

fig. 20 is another current flow diagram of an energy conversion device provided in an embodiment of the present application;

fig. 21 is a schematic structural diagram of a vehicle according to a seventh embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In order to explain the technical means of the present application, the following description will be given by way of specific examples.

As shown in fig. 1, the energy conversion device includes a reversible PWM rectifier 102, a motor coil 103, a power switch module 104, and an inductor 105, where the reversible PWM rectifier 102 is connected to the motor coil 103, a positive terminal of an external battery 101 is connected to a first bus terminal of the reversible PWM rectifier 102 and a first terminal of the power switch module 104, a negative terminal of the external battery 101 is connected to a second bus terminal of the reversible PWM rectifier 102 and a second terminal of the power switch module 104, a third terminal of the power switch module 104 is connected to a first terminal of the inductor, and a first terminal and a second terminal of an external charging/discharging port 106 are respectively connected to a second terminal of the inductor and a second terminal of the power switch module 104.

The motor can be a synchronous motor (including a brushless synchronous motor) or an asynchronous motor, the number of phases of the motor coil 103 is more than or equal to 2, the number of sets of motor windings is more than or equal to 2 (such as a double three-phase motor, a six-phase motor, a nine-phase motor and fifteen, the motor coil 103 is equal to fifteen), the connection points of the motor coil 103 form neutral points, the number of the specific motor coil 103 connection points depends on the parallel connection structure of the windings inside the motor, and the number of the parallel connection points of the motor coil 103 inside the motor is determined by the use condition of an actual scheme; the PWM in the reversible PWM rectifier 102 is Pulse width modulation (Pulse width modulation), the reversible PWM rectifier 102 comprises a multi-phase bridge arm, the multi-phase bridge arm is connected in common to form a first bus end and a second bus end, the number of the bridge arms is configured according to the phase number of the motor coil 103, each phase of inverter bridge arm comprises two power switch units, the power switch units can be in the types of transistors, IGBTs, MOSFET tubes, SiC tubes and other devices, the connection point of the two power switch units in the bridge arm is connected with one phase of coil in the motor, and the power switch units in the reversible PWM rectifier 102 can be switched on and off according to an external control signal; the power switch module 104 includes at least two power switch units, and the power switch module 104 can implement conduction of different loops in the energy conversion device according to the control signal; the inductor 105 is used for storing electric energy in an energy storage loop formed by the external battery 101, the power switch module 104 and the external charging port 106, and is also used for releasing electric energy in an energy storage freewheeling loop formed so as to realize boosting charging of the external battery or voltage reduction discharging of the external battery to an external electric device connected with the charging/discharging port; the external charging/discharging port 106 is a dc charging/discharging port, which is used to connect a dc power supply device or a dc power consumption device, and can receive a current output by the dc power supply device or output a current to the dc power consumption device, and the external battery 101 may be a battery in a vehicle, such as a power battery.

The energy conversion device further comprises a controller, the controller is connected with the reversible PWM rectifier 102 and sends control signals to the reversible PWM rectifier 102, the controller CAN comprise a vehicle control unit, a reversible PWM rectifier 102 control circuit and a BMS battery 101 manager circuit, the controller, the reversible PWM rectifier 102 control circuit and the BMS battery 101 manager circuit are connected through CAN lines, and different modules in the controller control the conduction and the disconnection of a power switch unit in the reversible PWM rectifier 102 according to the acquired information so as to realize the conduction of different current loops; the controller sends a control signal to the reversible PWM rectifier 102 in the energy conversion device, so that the current output by the external battery 101 or the power supply device connected to the charge/discharge port 106 flows through the motor coil 103 to generate heat, so as to heat the coolant in the cooling pipe flowing through the motor coil 103, and heat the power battery 101 when the coolant flows through the power battery 101.

As shown in fig. 2, the cooperative control method of the energy conversion apparatus includes:

and step 10, acquiring target heating power, target driving power and target charging and discharging power.

In this step, the target heating power refers to heat that the energy conversion device needs to generate when getting electricity from the external battery 101 or the power supply equipment connected to the external charging/discharging port 106 and generating heat through the motor coil 103; the target driving power is power generated when the energy conversion device takes power from an external battery 101 or a power supply device connected with an external charging and discharging port 106 and enables the motor to output torque when the power passes through the motor coil 103; the target charge/discharge power is power generated by the external battery 101 discharging the electric device through the energy conversion device when the external charge/discharge port 106 is connected to the electric device, or power generated by the power supply device charging the external battery 101 through the energy conversion device when the external charge/discharge port 106 is connected to the power supply device.

One of the target heating power, the target driving power and the target charging/discharging power may be zero and the other may not be zero, or one of them may not be zero and the other may not be zero, or all of them may not be zero.

And 20, acquiring target charging and discharging current output by an external charging and discharging port according to the target charging and discharging power, acquiring a first quadrature axis current and a first direct axis current in a synchronous rotation coordinate system based on the magnetic field orientation of the motor rotor according to the target driving power, and acquiring first heating power of the motor coil according to the first quadrature axis current and the first direct axis current.

In this step, when the external power supply is connected to the external charge/discharge port 106, the target charge/discharge current is calculated based on the charge/discharge pattern of the external power supply.

As an embodiment, as shown in fig. 3, the obtaining of the target charge and discharge current output from the external charge and discharge port according to the target charge and discharge power in step 20 includes:

and step 201, when the charging mode of the external power supply connected to the external charging and discharging port is a constant current charging and discharging mode, acquiring the target voltage of the external power supply according to the target charging and discharging power.

In this step, a target voltage U at the charge/discharge port 106 is obtained according to a formula P ═ U × I based on the target charge/discharge power required by the external battery 101, and I is the charge/discharge current of the external power supply.

Step 202, acquiring the actual voltage of a charge-discharge port, and acquiring a voltage difference value according to the target voltage and the actual voltage of the charge-discharge port;

and 203, carrying out closed-loop control on the voltage difference value to obtain target charging and discharging current output to the inductor.

In step 202 and step 203, the actual voltage of the charge/discharge port 106 is collected by the voltage sensor, the target voltage and the actual voltage of the charge/discharge port 106 are subjected to difference operation to obtain a voltage difference, and the target charge/discharge current is obtained through closed-loop control (e.g., PID (proportional, integral, differential, proportional-integral-derivative)).

In the embodiment, when the charging mode of the external power supply is detected to be the constant-current charging and discharging mode, the target voltage of the external power supply is obtained according to the target charging and discharging power, and the target charging and discharging current is calculated and obtained according to the target voltage and the actual voltage of the charging and discharging port 106, so that the target charging and discharging current is obtained in the constant-current charging and discharging mode.

As another embodiment, the obtaining of the target charge and discharge current output from the external charge and discharge port according to the target charge and discharge power in step 20 includes:

when an external power supply connected to an external charging and discharging port is in a constant voltage charging and discharging mode, the current of the external charging and discharging port is obtained according to the target charging and discharging power and is used as the target charging and discharging current output by the external charging and discharging port.

In this step, the external power source outputs a constant voltage U, and a target charge/discharge current in (i.e., a current on the inductor) is calculated according to a formula P ═ U × in ═ based on the target charge/discharge power required by the battery 101.

As an embodiment, the obtaining a first quadrature axis current and a first direct axis current in a synchronous rotating coordinate system based on the magnetic field orientation of the rotor of the motor according to the target driving power in step 20 includes:

and obtaining a torque output instruction according to the target driving power, and performing table look-up in a preset torque curve graph according to the torque output instruction to obtain a first quadrature axis current and a first direct axis current.

The technical scheme includes that the motor comprises three coordinate systems, namely a motor N-phase shaft coordinate system, a static coordinate system and a synchronous rotation coordinate system based on motor rotor magnetic field orientation, as shown in fig. 4 and 5, when the motor is a three-phase motor, the N-phase shaft coordinate system comprises a phase A shaft, a phase B shaft and a phase C shaft, the phase A shaft, the phase B shaft and the phase C shaft are different by 90 degrees in a three-dimensional state and are different by 120 degrees after being mapped to the static coordinate system, the static coordinate system comprises an alpha shaft and a beta shaft, the synchronous rotation coordinate system based on motor rotor magnetic field orientation is a d-q coordinate system (a straight shaft-cross shaft coordinate system), the coordinate system and a rotor rotate synchronously, the rotor magnetic field direction is taken as a d shaft, and the direction perpendicular to the rotor magnetic field is taken as a q shaft (the q shaft leads the d shaft by 90 degrees); in order to facilitate the control of the three-phase variables of the phase A shaft, the phase B shaft and the phase C shaft, the three-phase variables of the phase A shaft, the phase B shaft and the phase C shaft are generally converted into the variables of the alpha shaft and the beta shaft in a static coordinate system, then the variables of the alpha shaft and the beta shaft are converted into the d shaft and the q shaft of the direct current quantity of a synchronous rotating coordinate system, and the control of the three-phase variables of the phase A shaft, the phase B shaft and the phase C shaft is realized by controlling the d shaft and the q shaft of the direct current quantity; the transformation between different coordinate systems can be realized through coordinate transformation, and the transformation of an N-phase axis system to a two-phase static coordinate system is realized through Clark transformation, and generally no zero-axis vector is contained; converting the two-phase static coordinate system to an N-phase shafting through reverse Clark conversion; transforming an N-phase axis system into a two-phase static coordinate system by expanding Clark transformation, wherein the two-phase static coordinate system comprises a zero-axis vector; the method comprises the steps of converting a two-phase static coordinate system into a synchronous rotating coordinate system through PARK conversion, wherein the two-phase static coordinate system does not generally contain a zero-axis vector; the synchronous rotating coordinate system is converted into a two-phase static coordinate system through inverse PARK conversion; and the two-phase static coordinate system is converted into a synchronous rotating coordinate system by expanding PARK conversion, and the two-phase static coordinate system comprises a zero-axis vector.

Wherein, as shown in FIG. 6, the torque curve is plotted with the horizontal and vertical axes being the direct and quadrature axes, T_e1、T_e2、T_e3Respectively, a constant torque curve, and a voltage elliptic dotted line indicates the value ranges of id and iq when a certain voltage value is reached under a rotating speed omega; drawing a circle with the origin as the center of a circle and the resultant current vectors of id and iq as the radius to be tangent to a constant torque curve at H, F, D, A respectively, connecting O-H-F-D-A together to obtain an MTPA curve, namely a maximum torque current ratio curve, H, F, D, A corresponding to the minimum value points of id and iq on the constant torque curve, taking C point as the center of a circle, connecting a voltage ellipse with the constant torque curve at B, E, G, I respectively and intersecting the resultant current vectors and the voltage ellipse at A, B, and connecting the curves connected by B-E-G-I-C and the circular arc curve of the maximum current circle between A and B together to obtain an MTPV curve, namely a maximum torque voltage ratio curve, MTPA&MTPV curves and constant torque curves can be pre-calculated and stage-calibrated, typically using look-up tables or a combination of look-up tables and interpolationOr the MTPA is obtained by combining the torque Te and the rotating speed omega through a piecewise linear fitting method&And the MTPV curve or the constant torque curve controls quadrature axis current and direct axis current differently.

As an embodiment, for MTPA curves: the electromagnetic torque Te generated in the working process of the motor is controlled by d-axis current id, q-axis current id and iq, and the following equation is satisfied:

equation 1:

wherein Te is output torque of the shaft end of the motor, m is the phase number of a motor coil, Pn is the pole pair number of the motor, psi f represents a permanent magnet flux linkage of the motor, Ld is direct-axis inductance, Lq is quadrature-axis inductance, id is direct-axis current, and iq is quadrature-axis current.

In the motor, the resultant current vector equation satisfies:

equation 2:

therefore, the solution of the MTPA control current is equivalent to the solution of the extreme value of the following formula 3

Equation 3:

combining equation 2 and equation 3, the MTPA curve, i.e., the O-H-F-D-A, MTPV curve in the torque plot of FIG. 6, is solved:

equation 4:

wherein, ω e is the electrical angular velocity, Rs is the phase resistance of the motor coil, Ld and Lq are the winding inductance under a d-q axis coordinate system respectively, and ud and uq are the voltage under the d-q axis coordinate system respectively.

Equation 5:

in the torque graph of fig. 6, the above equations can be expressed as a current limit circle centered at the O point (0, 0) and a voltage limit ellipse centered at the C point (- ψ f/Ld, 0), respectively, on the current plane. The motor operates in the intersection region of the current limit circle and the voltage limit ellipse, and combines formula 4 and formula 5, namely an MTPV curve, namely an A-B-E-G-I-C curve in a torque curve chart of figure 6.

In this step, according to the torque required to be generated by the motor coil 103, a table lookup is performed on MTPA & MTPV curves in the torque curve graph, so as to obtain a first direct current id1 and a first quadrature current iq1 in a synchronous rotating coordinate system based on the motor rotor magnetic field orientation, where the first direct current id1 and the first quadrature current iq1 may be minimum values in the MTPA & MTPV curves.

As an embodiment, the obtaining the first heating power of the motor coil 103 according to the first quadrature axis current and the first direct axis current in step 30 includes:

the first heating power of the motor coil 103 is calculated according to the following formula:

equation 6:

where m is the number of phases of the motor coil 103, Rs is the phase resistance of the motor coil 103, id1 is the first direct current, iq1 is the first quadrature current, is_maxThe maximum value of the resultant vector current on the torque curve.

And 30, when the deviation between the first heating power and the target heating power is not in the preset range, adjusting the first quadrature-axis current and the first direct-axis current to the target quadrature-axis current and the target direct-axis current according to the target driving power, so that the deviation between the first heating power and the target heating power is in the preset range.

In this step, the deviation between the first heating power and the target heating power being not within the preset range means that the first heating power is greater than the maximum value of the preset range value or less than the minimum value of the preset range value, that is, when the first heating power is too large or too small, the first quadrature axis current and the first direct axis current are adjusted to adjust the first heating power to enable the first addition to be performedThe deviation between the thermal power and the target heating power is in a preset range, wherein the difference value is obtained by performing difference value operation on the first heating power and the target heating power, when the difference value is not in the preset range, the output torque is obtained according to the target driving power, a constant torque curve corresponding to the output torque is searched on a torque curve graph, and the constant torque curve is shown as constant torque curves Te1, Te2 and Te3 in the torque curve graph of FIG. 6, wherein Te1 is shown as Te1>Te2>Te3, the constant torque curve in the torque curve graph can be calculated in advance and calibrated on the stand, and the control current command is obtained from the torque by using a table lookup or a linear fitting method, wherein the preset range includes a preset upper limit range and a preset lower limit range, the preset upper limit range is a value greater than zero, and the preset lower limit range is a value less than zero. First by MTPA&The MTPV curve finds out a first direct current id1 and a first quadrature current iq1 meeting a torque command, the first direct current id1 and the first quadrature current iq1 are substituted into a formula 6 to obtain first heating power, whether a difference value between the first heating power and target heating power belongs to a preset range or not is checked, and when the difference value between the first heating power and the target heating power is smaller than a preset lower limit range, the MTPV curve slides along the constant torque curve and faces to the position ((id))²+(iq*)²) The increasing direction movement can be either towards the direction of increasing id positive half-axis or towards the direction of decreasing id negative half-axis, preferably the increasing direction movement is selected towards the direction of increasing id positive half-axis; when the difference between the first heating power and the target heating power is larger than the preset upper limit range, the constant torque curve is slid towards (id)²+(iq*)²) The decreasing direction moves until the difference is less than the preset upper limit range, if the slip is to the current torque, voltage (id)²+(iq*)²) Minimum point of (MTPA)&And when the MTPV curve meets the target direct-axis current and the target quadrature-axis current point of the torque command, and the difference value is still larger than the preset upper limit range, the current point is kept as the target direct-axis current and the target quadrature-axis current.

The method has the technical effects that the output torque is obtained according to the target driving power, the constant torque curve is searched on the torque curve graph according to the output torque, the direct-axis current and the quadrature-axis current are obtained according to the constant torque curve, the first heating power is obtained according to the selected direct-axis current and the quadrature-axis current, and then the direct-axis current and the quadrature-axis current are adjusted according to the relation between the target heating power and the first heating power, so that the first heating power is matched with the target heating power, and the cooperative work among the output torque process, the heating process and the charging process is realized.

Further, the cooperative control method further includes:

when the target driving power is converted from the first target driving power to the second target driving power, acquiring a composite current vector amplitude according to a target quadrature-axis current and a target direct-axis current corresponding to the first target driving power;

acquiring a first intersection coordinate amplitude and a second intersection coordinate amplitude which are formed by a circle and a torque curve corresponding to second target driving power, wherein the circle takes an origin in a preset torque curve graph as a circle center and a synthetic current vector amplitude as a radius;

respectively acquiring a first distance between a first intersection point coordinate and a coordinate frame formed by the target quadrature-axis current and the target direct-axis current and a second distance between a second intersection point coordinate and a coordinate frame formed by the target quadrature-axis current and the target direct-axis current;

and determining the coordinate of the intersection point corresponding to the smaller value of the first distance and the second distance as the target direct axis current and the target quadrature axis current of the second target driving power.

Specifically, after a target direct axis current id and a target quadrature axis current iq meeting the conditions are obtained from the heating power, when the target driving power is changed, a current torque output command is obtained according to the current target driving power, and the magnitude of a resultant current vector of the target corresponding to the first target driving power is found on a constant torque curve of the current torque value ((id))²+(iq*)²) And current circles are intersected, and current points with the nearest distances of id and iq serve as target direct axis current id and target quadrature axis current iq of the current torque value, so that the cooperative work among the output torque process, the heating process and the charging process after the output torque is changed is realized.

And step 40, when the deviation between the first heating power and the target heating power is in a preset range, setting the first quadrature-axis current and the first direct-axis current as the target quadrature-axis current and the target direct-axis current.

In this step, a first direct current id1 and a first quadrature current iq1 meeting a torque command are obtained through an MTPA & MTPV curve in a torque curve graph, the first direct current id1 and the first quadrature current iq1 are substituted into a formula 6 to check whether the required heating power is met, and if the first heating power is within a preset range of a target heating power error, the first quadrature current and the first direct current are directly set as a target quadrature current and a target direct current.

And 50, acquiring a sampling current value, a charging and discharging current sampling value and a motor rotor position on each phase of coil, calculating the duty ratio of each phase of bridge arm in the reversible PWM rectifier according to the target quadrature axis current, the target direct axis current, the sampling current value on each phase of coil and the motor rotor position, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the charging and discharging current sampling value.

In this step, as a first embodiment, as shown in fig. 7, step S50 includes:

and S501, acquiring the actual quadrature axis current iq and the actual direct axis current id of each set of windings according to the sampling current value of each phase coil and the position of the motor rotor.

As an embodiment, as shown in fig. 8, the obtaining of the actual quadrature axis current iq and the actual direct axis current id of each set of windings according to the sampled current value on each phase coil and the motor rotor position in step S501 includes:

and S5011, carrying out clark coordinate transformation on the sampling current value of each phase of coil to obtain current values i alpha and i beta of a static coordinate system.

In this step, three-phase or multi-phase currents on the motor coil 103 are converted into two-phase currents i α and i β of a stationary coordinate system, and an N-phase axis coordinate system is converted into a two-phase stationary coordinate system by Clark coordinate conversion.

The expanded Clark (2/m is constant amplitude Clark, and constant power conversion is similar) conversion formula of the multiphase motor:

the extended inverse Clark (constant amplitude Clark) transformation formula for multiphase motors:

the motor phase number m, alpha is 2 pi/m, and is the electrical angle of the phase difference between two adjacent windings in each set of windings; for example, a three-phase four-wire motor is described as an example: measuring 2-phase currents ib and ic in the three-phase coil, calculating ia according to ia-ib-ic, converting the currents (ia, ib, ic) into current values i alpha and i beta on a two-phase stationary coordinate system through Clark (Clark), wherein i alpha is-ib-ic, and i beta is,

Wherein, Clark coordinate transformation formula is as follows:

and S5012, carrying out park coordinate transformation according to the current values i alpha and i beta of the static coordinate system and the position of the motor rotor to obtain the actual quadrature axis current iq and the actual direct axis current id.

In this step, the two-phase current values i α and i β of the stationary coordinate system are converted into quadrature axis current and direct axis current of the synchronous rotating coordinate system based on the motor rotor magnetic field orientation, the motor rotor position may be an electrical angle θ between the motor rotor direct axis and the a phase winding of the motor coil 103, if the motor is an asynchronous motor, θ ═ t (rotor rotation speed Wr + rotation difference Ws) × t, and the rotor position is read by a rotation transformer or other position sensor or a position-free sensor, so as to obtain θ.

The actual quadrature-axis current iq and the actual direct-axis current id can be obtained by the following Park coordinate transformation:

expanded Park coordinate transformation:

expanded inverse Park coordinate transformation:

where θ is the motor rotor position.

S502, respectively carrying out closed-loop control to obtain direct-axis reference voltage and quadrature-axis reference voltage according to the target quadrature-axis current iq, the actual quadrature-axis current iq, the target direct-axis current id and the actual direct-axis current id, and obtaining the duty ratio D of each phase of bridge arm according to the direct-axis reference voltage, the quadrature-axis reference voltage and the position of the motor rotor₁1、D ₁2…D₁m, wherein m is the number of phases, D₁And m represents the duty ratio of the m-th phase motor coil.

As an embodiment, as shown in fig. 9, the obtaining of the quadrature reference voltage and the direct reference voltage by performing the closed-loop control according to the target quadrature-axis current iq and the actual quadrature-axis current iq, the target direct-axis current id and the actual direct-axis current id in step S502 includes:

step S5021, calculating target quadrature axis current iq and actual quadrature axis current iq to obtain a quadrature axis current difference value, and calculating target direct axis current id and actual direct axis current id to obtain a direct axis current difference value;

and S5022, respectively controlling the quadrature axis current difference and the direct axis current difference (for example PID control) to obtain a quadrature axis reference voltage Uq and a direct axis voltage difference Ud.

In the two steps, the actual quadrature axis current iq is subtracted from the target quadrature axis current iq and then subjected to control (for example, PID control) to obtain the quadrature axis reference voltage Uq, and similarly, the actual direct axis current id is subtracted from the target direct axis current id and then subjected to control (for example, PID control) to obtain the direct axis reference voltage Ud.

As an embodiment, as shown in FIG. 10, the stepsIn step S602, the duty ratio D of each phase bridge arm is obtained according to the direct-axis reference voltage, the quadrature-axis reference voltage, and the motor rotor position₁1、D ₁2…D₁m, comprising:

and S5023, performing inverse park coordinate transformation on the quadrature axis reference voltage Uq, the direct axis reference voltage Ud and the position of the motor rotor to obtain voltages Ualpha and Ubeta of a static coordinate system.

In this step, the voltages U α and U β of the stationary coordinate system may be obtained by the following inverse Park coordinate transformation formula:

and S5024, carrying out space vector pulse width modulation conversion on the voltages Ualpha and Ubeta of the static coordinate system to obtain the duty ratio of each phase of bridge arm.

In this step, the voltages U α and U β of the stationary coordinate system are subjected to SVPWM (Space Vector Pulse Width Modulation) algorithm to obtain the duty ratio D of the bridge arm in the reversible PWM rectifier 102₁1、D ₁2…D₁m。

And S503, carrying out closed-loop control according to the target charging and discharging current and the charging and discharging current sampling value to obtain the duty ratio of a bridge arm in the power switch module.

As an embodiment, step S503 includes:

and calculating according to the target charging and discharging current in and the charging and discharging current sampling value, and obtaining the duty ratio of the bridge arm in the power switch module 104 after PID control.

The first embodiment of step S50 includes step S501, step S502, and step S503, and this embodiment realizes cooperative work of the heating process, the charge/discharge process, and the output torque process by resolving the parameter values of the multi-phase motor into the synchronous rotation coordinate system to perform closed-loop control.

As a second embodiment, as shown in fig. 11, the step S50 of calculating the duty ratio of each phase arm in the reversible PWM rectifier according to the target quadrature-axis current, the target direct-axis current, the sampled current value on each phase coil, and the motor rotor position, and calculating the duty ratio of the arm in the power switch module according to the target charge-discharge current and the sampled charge-discharge current includes:

s511, obtaining a target current value of each phase coil according to the target quadrature axis current, the target direct axis current, the position of the motor rotor and the target charging and discharging current;

as an embodiment, step S511 includes:

and performing inverse park and inverse lock coordinate transformation according to the target quadrature axis current iq, the target direct axis current id and the motor rotor position to obtain a target current value of each phase of coil.

And S512, acquiring the reference voltage of each phase bridge arm according to the sampling current value of each phase coil and the target current value of each phase coil.

And S513, acquiring the duty ratio of each phase of bridge arm according to the reference voltage of each phase of bridge arm.

And S514, performing closed-loop control according to the target charging and discharging current and the charging and discharging current sampling value to obtain the duty ratio of the bridge arm in the power switch module.

In the above steps, the sampled current value on each phase coil and the target current value of each phase coil are subjected to closed-loop regulation, and the closed-loop regulation may be PID control, PR control, synovial control, or the like.

The present embodiment is different from the above embodiments in that the parameter values of the multi-phase motor are calculated in the phase coordinate system to perform closed-loop control, and the cooperative work of the heating process, the charging and discharging process, and the output torque process is realized.

As for the step S50, as a third embodiment, as shown in fig. 12, the step S50 includes:

step 521, obtaining a target alpha-axis current and a target beta-axis current of a motor static coordinate system according to the target quadrature-axis current iq, the target direct-axis current id and the rotor position;

s522, acquiring actual alpha-axis current and actual beta-axis current of a motor static coordinate system according to the sampling current value on each phase coil;

s523, acquiring reference voltages Ualpha and Ubeta of a motor coil in a static coordinate system according to the target alpha axis current, the target beta axis current, the actual alpha axis current and the actual beta axis current;

s524, carrying out space vector modulation transformation on the reference voltages Ualpha and Ubeta of the static coordinate system to obtain the duty ratio of each phase of bridge arm;

and S525, carrying out closed-loop control according to the target charging and discharging current and the charging and discharging current sampling value to obtain the duty ratio of a bridge arm in the power switch module.

The present embodiment is different from the above embodiments in that the parameter values of the multi-phase motor are calculated in the stationary coordinate system to perform closed-loop control, and the cooperative work of the heating process, the charging and discharging process, and the output torque process is realized.

The embodiment of the application provides a cooperative control method of an energy conversion device, which includes the steps of adopting the energy conversion device including a reversible PWM rectifier and a motor coil, enabling the energy conversion device to be connected with an external battery and a power supply device or an electric device through a charging and discharging port, obtaining target heating power, target driving power and target charging and discharging power, obtaining target charging and discharging current output by the external charging and discharging port according to the target charging and discharging power, obtaining first quadrature axis current and first direct axis current according to the target driving power, obtaining first heating power of the motor coil according to the first quadrature axis current and the first direct axis current, adjusting the first quadrature axis current and the first direct axis current according to a relation between the first heating power and the target heating power to obtain target quadrature axis current and target direct axis current, and then adjusting the first quadrature axis current and the first direct axis current according to the target quadrature axis current, The method comprises the steps of calculating the duty ratio of each phase of bridge arm in a PWM rectifier according to target straight-axis current, target charge-discharge current, sampling current value on each phase of coil and motor rotor position, calculating the duty ratio of the bridge arm in a power switch module according to the target charge-discharge current and the sampling value of the charge-discharge current, controlling the on-off of a switch device on each phase of bridge arm in the PWM rectifier and a switch device on the bridge arm in the power switch module according to the duty ratio, realizing that current output by an external battery or power supply equipment flows through a motor coil to generate heat so as to heat cooling liquid flowing through a cooling pipe of the motor coil, heating a power battery when the cooling liquid flows through the power battery and heating the power battery by combining the heat generated by the charging or discharging of the battery, saving an additional power battery heating device, reducing the cost of the whole device and ensuring the charging and discharging of the, meanwhile, the cooperative work of two or three of the charging and discharging process, the heating process and the torque output process is realized, namely, the cooperative work of the external power supply equipment (such as a charging pile) discharging the battery charging process, the motor heating process and the motor torque output process is realized; or the battery discharges to supply power to external electric equipment (such as vehicles), and the three work cooperatively in the heating process of the motor and the torque output process of the motor.

An embodiment of the present application provides a cooperative control method of an energy conversion device, as shown in fig. 13, when a target charge-discharge power is zero, and a target charge-discharge current and a first heating power are zero, the cooperative control method includes:

s11, acquiring target heating power and target driving power;

s21, acquiring a first quadrature axis current and a first direct axis current according to the target driving power, and acquiring a first heating power of the motor coil according to the first quadrature axis current and the first direct axis current;

s31, when the deviation between the first heating power and the target heating power is not within a preset range, adjusting the first quadrature-axis current and the first direct-axis current to the target quadrature-axis current and the target direct-axis current according to the target driving power, and enabling the deviation between the first heating power and the target heating power to be within the preset range;

s41, when the deviation between the first heating power and the target heating power is within a preset range, setting the first quadrature-axis current and the first direct-axis current as a target quadrature-axis current and a target direct-axis current;

and S51, acquiring a sampling current value on each phase coil and a position of a motor rotor, and calculating the duty ratio of each phase bridge arm in the reversible PWM rectifier according to the target quadrature axis current, the target direct axis current, the sampling current value on each phase coil and the position of the motor rotor.

The cooperative control method for the energy conversion device provided by the second embodiment of the present application is different from the first embodiment in that the target charge and discharge power is zero, the heating of the motor coil 103 and the control of the output torque of the motor are controlled to be performed simultaneously, the energy conversion device including the reversible PWM rectifier 102 and the motor coil 103 is adopted, when the energy conversion device is connected with the external battery 101 and connected with the power supply equipment or the electric equipment through the charge and discharge port 106, the target heating power and the target driving power are obtained, the first heating power is obtained according to the target driving power, the first quadrature axis current and the first direct axis current are adjusted according to the relationship between the first heating power and the target heating power to obtain the target quadrature axis current and the target direct axis current, then the duty ratio of each phase bridge arm in the PWM rectifier is calculated according to the target quadrature axis current, the target direct axis current, the sampling current value on each phase coil and the position of the rotor of the motor, the on-off of the switching device on each phase of bridge arm in the PWM rectifier is controlled according to the duty ratio, so that the current output by an external battery 101 or power supply equipment flows through the motor coil 103 to generate heat to heat the cooling liquid in the cooling pipe flowing through the motor coil 103, when the cooling liquid flows through the power battery 101, the power battery 101 is heated, an additional power battery 101 heating device can be omitted, the cost of the whole device is reduced, the charging and discharging of the battery 101 in a low-temperature state is guaranteed, and the cooperative work of the heating process and the torque output process is realized.

A third embodiment of the present application provides a cooperative control method for an energy conversion device, as shown in fig. 14, when a target heating power is zero, the cooperative control method includes:

s12, acquiring target charge-discharge power and target driving power;

s22, acquiring target charge-discharge current output by an external charge-discharge port according to the target charge-discharge power;

s32, acquiring a first quadrature axis current and a first direct axis current according to the target driving power, and setting the first quadrature axis current and the first direct axis current as a target quadrature axis current and a target direct axis current;

and S42, acquiring a sampling current value on each phase coil and a position of a motor rotor, calculating the duty ratio of each phase bridge arm in the reversible PWM rectifier according to the target quadrature axis current, the target direct axis current, the sampling current value on each phase coil and the position of the motor rotor, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the sampling value of the charging and discharging current.

The third embodiment of the application provides a cooperative control method for an energy conversion device, which is different from the first embodiment in that target heating power is zero, charging and discharging of a motor coil are controlled, output torque of a motor is controlled to be performed simultaneously, target charging and discharging power and target driving power are obtained, the duty ratio of each phase of bridge arm in a reversible PWM rectifier is calculated according to the target driving power, the sampling current value on each phase of coil and the position of a motor rotor, the duty ratio of the bridge arm in a power switch module is calculated according to the target charging and discharging power and the sampling value of the charging and discharging current, and cooperative work of the two in a heating process and a torque output process is achieved.

A fourth embodiment of the present application provides a cooperative control method for an energy conversion device, as shown in fig. 15, when a target driving power is zero, the cooperative control method includes:

s13, acquiring target heating power and target charge-discharge power;

s23, acquiring target charge-discharge current output by an external charge-discharge port according to the target charge-discharge power;

s33, obtaining target quadrature axis current and target direct axis current according to the target heating power;

s43, acquiring a sampling current value, a charging and discharging current sampling value and a rotor electric angle on each phase of coil, calculating the duty ratio of each phase of bridge arm in the reversible PWM rectifier according to the target quadrature axis current, the target direct axis current, the target charging and discharging current, the sampling current value on each phase of coil and the rotor electric angle of the motor at the rotor position, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the charging and discharging current sampling value.

The fourth embodiment of the application provides a cooperative control method for an energy conversion device, which is different from the first embodiment in that target driving power is zero, charging and discharging of a motor coil are controlled, heating of the motor coil is controlled to be performed simultaneously, target heating power and target charging and discharging power are obtained, the duty ratio of each phase of bridge arm in a reversible PWM rectifier is calculated according to the target heating power and the target charging and discharging power, the collected sampling current value of each phase of coil and the position of a motor rotor, the duty ratio of the bridge arm in a power switch module is calculated according to the target charging and discharging power, cooperative work of a heating process and a charging and discharging process is achieved, and zero torque output is achieved at the same time.

The present application is described in detail below with specific vector control diagrams:

fig. 16 is a block diagram of vector control of an n-phase motor according to the present invention, which relates to vector control of a multi-phase motor, and solves a multi-phase motor vector to a synchronous rotating coordinate system for closed-loop control, and fig. 17 is a block diagram corresponding to fig. 16, which exemplifies a three-phase motor as an example of a three-phase motor vector control system. The control process comprises the following steps: the controller receives a charge and discharge instruction, a torque output instruction and a heating power instruction, wherein the charge and discharge instruction is a given voltage value or a given current value, a voltage target is obtained according to the charge and discharge instruction, a charge port voltage is obtained and is controlled with the voltage target to obtain a target charge and discharge current in, an actual charge and discharge current in is obtained, the target charge and discharge current in and the actual charge and discharge current in are subjected to difference and closed-loop control (such as PID control), and then the duty ratio D0 of the power switch module 104 is output; and carrying out an instruction resolving process according to the output torque and the heating power to obtain a target quadrature axis current iq and a target direct axis current id, sampling three-phase current values ia, ib and ic, converting the three-phase current values into a dq coordinate system through coordinate transformation to obtain an actual direct axis current id and an actual quadrature axis current iq, respectively carrying out difference with the target direct axis current id and the target quadrature axis current iq, controlling and outputting a Ud target value and a Uq target value through PID, carrying out inverse Park transformation on the Ud and Uq to obtain U alpha and U beta, and transmitting the U alpha and the U beta to a Space Vector Pulse Width Modulation (SVPWM) algorithm to obtain three-phase bridge arm duty ratios Da, Db and Dc of the inverter.

The present application is described in more detail below with reference to different modes of the energy conversion device:

when the charging and discharging instruction, the torque output instruction and the heating power instruction are as follows: when at most one of the three instructions is not zero, the instruction resolving allocation is carried out according to the following mode:

the first mode of operation: when the charging and discharging instruction, the torque output instruction and the heating power instruction (the instruction is the required power) are all zero, all the switches are in an off state.

The second working mode is as follows: only torque output commands:

the charging and discharging command is 0, namely the charging and discharging current in is 0, the heating power command is 0, the command resolving process is according to the MTPA & MTPV curve in the torque curve chart of FIG. 6, two required values of target quadrature axis current iq and target direct axis current id corresponding to the coordinate axes of the synchronous rotation coordinate system d-q are checked or calculated according to the torque output command and the current rotating speed ω e of the motor, the torque command requirement is ensured, at the moment, the current loop of the target charging and discharging current in does not perform control operation, and the energy required by the torque command is from the external battery 101 or the external power supply equipment.

The third mode of operation: only the heating power command:

the charging and discharging command is 0, namely the charging and discharging current in is 0, the torque output command is 0 or a smaller value, namely the target quadrature axis current iq is 0 or iq is a smaller value (meshing gear gap for preventing the motor rotor from shaking), and a vector in the direction of the target direct axis current id is given; given heating power, according to a formula of a formula 7, solving id, wherein id can be positive or negative, and the preferable id takes a positive value, namely the direction of the enhanced magnetic field, or superposing the obtained id on a positive selected high-frequency signal, wherein the heating of the battery 101 is increased when the impedance of the battery 101 is larger; the heating power can be calculated in advance and calibrated in a rack mode, and the control current commands id and iq are obtained from the heating power by using a table lookup method or a linear fitting method.

Equation 7:

and giving a judgment mode according to the current instruction, obtaining id, iq and in after the process of calculation, wherein the target in current loop does not perform control operation, and the energy required by the heating instruction comes from the battery 101 or external power supply equipment.

A fourth mode of operation: only the charge and discharge instructions are as follows: the torque output command is 0, the heating power command is 0, iq ═ 0, id ═ 0, and in ≠ 0.

When the external power supply connected to the external charging and discharging port 106 is in a constant current charging and discharging mode, the controller adopts voltage and current double closed loop control: and the current command in is a charging and discharging voltage command U and an output quantity after voltage sampling closed-loop control.

When the external power supply connected to the external charging and discharging port 106 is in a constant current charging and discharging mode, the motor controller can also adopt single-voltage upper closed-loop control: only in the voltage closed loop link, the output quantity after the voltage instruction U and the voltage sampling closed loop control is directly converted into the bridge arm duty ratio, and the current on the sampling inductor is used for obtaining the in.

When the external power supply connected to the external charging and discharging port 106 is in a constant voltage charging and discharging mode, the motor controller adopts single current upper closed-loop control: the current command in is directly given by a battery manager without a voltage closed loop.

And obtaining the targets id, iq and in through a vector control solving process.

Wherein in 0 is charged and in 0 is discharged.

When the charging and discharging instruction, the torque output instruction and the heating power instruction are as follows: when at least two of the three instructions are not zero, the instruction resolving allocation is carried out according to the following mode:

the fifth working mode: only a charge and discharge instruction and a heating power instruction are required, and a torque output instruction is 0:

and (3) charge and discharge commands:

when the external power supply connected to the external charging/discharging port 106 is in a constant current charging/discharging mode, the motor controller may adopt voltage-current double closed-loop control: the current instruction in is a charging and discharging voltage instruction U and an output quantity after voltage sampling closed-loop control; and sampling the current in on the inductor to perform current closed-loop control.

When the external power supply connected to the external charging/discharging port 106 is in a constant voltage charging/discharging mode, the motor controller may further adopt single-current upper closed-loop control: the current instruction in is directly issued by a battery 101 manager and given without a voltage closed loop link, and the current in on the inductor is sampled to carry out current closed loop control;

when the external power supply connected to the external charging and discharging port 106 is in a constant current charging and discharging mode, the motor controller can also adopt single-voltage upper closed-loop control: only the voltage closed loop link is adopted, and the output quantity after the voltage instruction U and the voltage sampling closed loop control is directly converted into the bridge arm duty ratio.

Heating power command: given the heating power, solving id according to formula 8, wherein id may be positive or negative, and preferably, id takes a positive value, namely, the direction of the enhanced magnetic field; the heating power can be calculated in advance and calibrated in a rack mode, and target currents id and iq are obtained from the heating power by using a table lookup method or a linear fitting method.

Equation 8:

and obtaining targets id, iq and in according to the calculation process of the charging and discharging command and the heating power command. In >0 during charging and in <0 during discharging.

Sixth mode of operation: only a charging and discharging instruction and a torque output instruction are required, and a heating power instruction is 0:

and (3) charge and discharge commands:

when the external power supply connected to the external charging/discharging port 106 is in a constant current charging/discharging mode, the motor controller may adopt voltage/current upper closed-loop control: and the current instruction in is the output quantity of the charge-discharge voltage instruction U and the voltage sampling closed-loop control, and the current in on the inductor is sampled to carry out the current closed-loop control.

When the external power supply connected to the external charging/discharging port 106 is in a constant voltage charging/discharging mode, the motor controller may further adopt single-current upper closed-loop control: the current instruction in is directly issued by a battery 101 manager, a voltage closed loop link is not provided, the current in on the inductor is sampled, and current closed loop control is carried out.

When the external power supply connected to the external charging and discharging port 106 is in a constant current charging and discharging mode, the motor controller can also adopt single-voltage upper closed-loop control: only the voltage closed loop link is adopted, the output quantity after the voltage instruction U and the voltage sampling closed loop control is directly converted into the bridge arm duty ratio, and the current in on the inductor is sampled.

A torque output command: in the command resolving process, according to the MTPA & MTPV curves in the torque curve chart of FIG. 6, the torque output command finds out the requirements of two values id and iq corresponding to the coordinate axis of the synchronous rotation coordinate system dq, and the requirements of the torque command are given;

after the calculation process, the targets id, iq and in are obtained, wherein in is greater than 0 during charging and in is less than 0 during discharging.

Seventh mode of operation: only a heating power instruction and a torque output instruction are required, and a charging and discharging instruction is 0:

heating power command:

equation 9:

a torque output command: the constant torque curve is calculated, see constant torque curves Te1, Te2 and Te3 in the torque curve chart of FIG. 6, wherein Te1> Te2> Te3, the constant torque curve in the torque curve chart can be calculated in advance and calibrated by a rack, and the control current command is obtained from the torque by using a table lookup method or a linear fitting method. Firstly, finding out id and iq meeting a torque command through an MTPA & MTPV curve, substituting the id and iq into a formula 9 to check whether the required heating power is met, if the required heating power is not met, sliding along a constant torque curve, moving towards the direction that an id positive half shaft is increased or moving towards the direction that an id negative half shaft is decreased, preferably, moving towards the direction that the id positive half shaft is increased, iterating until the formula 9 is met or the error range specified by the formula 9 is met, calculating the heating power in advance and calibrating the heating power in a rack mode, and obtaining the control current commands id and iq from the heating power by using a table lookup or linear fitting method.

At the moment, the target in current loop does not carry out control operation, and after the process of calculation, targets id, iq and in are obtained.

The eighth mode of operation: the charge and discharge command, the heating power command and the torque output command are all not zero.

And (3) charge and discharge commands: when the external power supply connected to the external charging/discharging port 106 is in a constant current charging/discharging mode, the motor controller may adopt voltage/current upper closed-loop control: and the current instruction in is the output quantity of the charge-discharge voltage instruction U and the voltage sampling closed-loop control, and the current in on the inductor is sampled to carry out the current closed-loop control.

When the external power supply connected to the external charging/discharging port 106 is in a constant voltage charging/discharging mode, the motor controller may adopt single-current upper closed-loop control: the current instruction in is directly issued by a battery 101 manager, a voltage closed loop link is not provided, the current in on the inductor is sampled, and current closed loop control is carried out.

When the external power supply connected to the external charging and discharging port 106 is in a constant current charging and discharging mode, the motor controller may adopt single-voltage upper closed-loop control: only the voltage closed loop link is adopted, the output quantity after the voltage instruction U and the voltage sampling closed loop control is directly converted into the bridge arm duty ratio, and the current in on the inductor is sampled.

Heating power command:

equation 10:

a torque output command: the constant torque curve in the torque curve graph can be calculated in advance and calibrated by a rack, and a control current command is obtained from the torque by generally using a table look-up method or a linear fitting method. First by MTPA&The MTPV curve finds out id and iq which satisfy the torque command, and the id and iq are substituted into formula 8 to check whether the required heating power is satisfied, if not, the MTPV curve slides along the constant torque curve to move to (id)²+(iq*)²) The direction of increasing movement may be towards i_dThe positive half axis is moved in the direction of increasing, and may be directed toward i_dThe negative half axis is shifted in the direction of decreasing, preferably the selection is shifted in the direction of increasing id positive half axis, andthe line iteration may know that equation 10 is satisfied or within the error range specified by equation 10. The heating power can be calculated in advance and calibrated in a rack mode, and the control current commands id and iq are obtained from the heating power by using a table lookup method or a linear fitting method.

And obtaining the targets id, iq and in after the calculation process.

The solar high-voltage line deicing vehicle or the lunar vehicle is used in the scene of charging and discharging instructions, heating power instructions and torque output instructions.

As the circuit configuration of the energy conversion device, the following circuit configuration may be adopted:

fig. 18 is a circuit diagram of an energy conversion device provided in this embodiment, the energy conversion device includes a reversible PWM rectifier 102, a motor coil 103, and a power switch module 104, and further includes a switch K1, a switch K2, a resistor R, a switch K3, and a capacitor C1, a positive electrode of an external battery 101 is connected to a first end of the switch K1 and a first end of the switch K2, a second end of the switch K1 is connected to a first end of the resistor R, a second end of the switch K2 and a second end of the resistor R are connected to a first end of the capacitor C1, a negative electrode of the battery 10 is connected to a first end of the switch K3, a second end of the switch K3 is connected to a second end of the capacitor C1, the reversible PWM rectifier 102 includes a three-phase bridge arm, the first-phase bridge arm includes a first power switch unit and a second power switch unit connected in series, the second-phase arm includes a third power switch unit and a fourth power switch unit connected in series, the third-phase arm includes a fifth power switch unit and a, the power switch module 104 comprises a seventh power switch unit and an eighth power switch unit which are connected in series, an input end of the first power switch unit, an input end of the third power switch unit and an input end of the fifth power switch unit are connected in common to form a first junction end and are connected with a first end of a capacitor C1, the first junction end is further connected with an input end of the seventh power switch unit, an output end of the second power switch unit, an output end of the fourth power switch unit and an output end of the sixth power switch unit are connected in common to form a second junction end and are connected with a second end of a capacitor C1, the second junction end is further connected with an output end of the eighth power switch unit, the first power switch unit comprises a first upper bridge arm VT1 and a first upper bridge diode 1, the second power switch unit comprises a second lower bridge arm VT2 and a second lower bridge diode VD2, the third power switch unit comprises a third upper bridge arm VD3 and a third upper bridge diode VD3, the fourth power switch unit comprises a fourth lower bridge arm VT4 and a fourth lower bridge diode VD4, the fifth power switch unit comprises a fifth upper bridge arm VT5 and a fifth upper bridge diode VD5, the sixth power switch unit comprises a sixth lower bridge arm VT6 and a sixth lower bridge diode VD6, the seventh power switch unit comprises a seventh upper bridge arm VT7 and a seventh upper bridge diode VD7, the eighth power switch unit comprises an eighth lower bridge arm VT8 and an eighth lower bridge diode VD8, the motor coil 103 comprises a set of three-phase windings, the first phase coil is connected with the midpoint of the first phase arm, the second phase coil is connected with the midpoint of the second phase arm, the third phase coil is connected with the midpoint of the third phase arm, the first phase coil, the second phase coil and the third phase coil are connected together to form a neutral point, the energy conversion module further comprises a switch K4, a switch K5, an inductor L and a capacitor C2, and the first end and the second end of the charge and discharge port 106 are respectively connected with the second end of the switch K4 and the second end of the switch 5, the first terminal of the switch K4 is connected to the second terminal of the inductor L and the first terminal of the capacitor C2, the first terminal of the inductor L is connected to the output terminal of the seventh power switch cell and the input terminal of the eighth power switch cell in the power switch module 104, and the first terminal of the switch K5 is connected to the second terminal of the capacitor C2 and the second bus terminal.

As shown in fig. 19 and 20, when the energy conversion device is connected to the external vehicle, the energy storage process and the energy storage release process of the charging process are performed, and at the same time, the energy conversion device can perform heating and output torque.

When the charging and discharging ports are connected with external electric equipment, the battery 101, the reversible PWM rectifier 102 and the motor coil 103 form a driving loop and a heating loop, the battery 101, the power switch module 104 and the charging and discharging port 106 form a discharging loop, the controller controls the conduction time and duration of the reversible PWM rectifier 102 and the power switch module 104, so that the current output by the battery flows through the first power switch unit, the first phase coil L1, the second phase coil L2, the third phase coil L3, the fourth power switch unit and the sixth power switch unit to form a driving energy storage loop and a heating energy storage loop, the current output by the battery also flows through the seventh power switch unit, the inductor L and the charging and discharging port 106 to form a discharging energy storage loop, the first phase coil L1, the second phase coil L2, the third phase coil L3, the third power switch unit, the fifth power switch unit and the first power switch unit form a driving energy storage release loop and a heating energy storage release loop, the inductor L, the charging and discharging port 106, and the eighth power switch unit form a discharging energy storage and release circuit, and the controller enables the driving energy storage circuit, the heating energy storage circuit, and the discharging energy storage circuit to simultaneously operate and the driving energy storage and release circuit, the heating energy storage and release circuit, and the discharging energy storage and release circuit to simultaneously operate according to the calculated duty ratio of the reversible PWM rectifier 102 and the duty ratio of the power switch module.

An embodiment five of the present application provides a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and the computer program is implemented to implement the steps of the first to fourth embodiments when executed by a processor.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware related to instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, the computer program can include the processes of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules, so as to perform all or part of the functions described above.

The sixth embodiment of the present application provides a cooperative control device of an energy conversion device, the energy conversion device includes a reversible PWM rectifier 102, a motor coil 103, a power switch module 104, and an inductor 105, the reversible PWM rectifier 102 is connected to the motor coil 103, a positive terminal of an external battery 101 is connected to a first bus terminal of the reversible PWM rectifier 102 and a first terminal of the power switch module 104, a negative terminal of the external battery 101 is connected to a second bus terminal of the reversible PWM rectifier 102 and a second terminal of the power switch module 104, a third terminal of the power switch module 104 is connected to a first terminal of the inductor 105, and a first terminal and a second terminal of an external charge/discharge port 106 are respectively connected to a second terminal of the inductor 105 and a second terminal of the power switch module 104;

the cooperative control apparatus includes:

the target current obtaining module is used for obtaining target charging and discharging current output by the external charging and discharging port according to target charging and discharging power, obtaining first quadrature axis current and first direct axis current in a synchronous rotating coordinate system based on motor rotor magnetic field orientation according to the target driving power, and obtaining first heating power of the motor coil according to the first quadrature axis current and the first direct axis current; when the deviation between the first heating power and the target heating power is not within a preset range, adjusting the first quadrature-axis current and the first direct-axis current to a target quadrature-axis current and a target direct-axis current according to the target driving power, and enabling the deviation between the first heating power and the target heating power to be within the preset range;

and the duty ratio acquisition module is used for acquiring a sampling current value, a charging and discharging current sampling value and a rotor electrical angle of each phase of coil, calculating the duty ratio of each phase of bridge arm in the reversible PWM rectifier according to a target quadrature axis current, a target direct axis current, a target charging and discharging current, the sampling current value of each phase of coil and a motor rotor electrical angle, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the charging and discharging current sampling value.

The seventh embodiment of the application provides a vehicle, and the electric automobile further comprises the energy conversion device provided by the sixth embodiment.

As shown in fig. 21, the heating and cooling circuit of the battery pack includes the following circuits: a motor drive system cooling loop, a battery cooling system loop, and an air conditioning system cooling loop. The battery cooling system loop is fused with the air-conditioning cooling system through the heat exchange plate; and the battery cooling system loop is communicated with the motor driving system cooling loop through the four-way valve. The motor drive system cooling circuit connects and disconnects the radiator by switching of the three-way valve. The motor driving system cooling loop and the battery cooling system loop are switched through the valve body, the flow direction of cooling liquid in the pipeline is changed, the flow direction of the cooling liquid heated by the motor driving system is enabled to flow to the battery cooling system, and heat is transferred from the motor driving system to the battery cooling; when the motor driving system is in a non-heating mode, the cooling liquid of the motor driving system flows through a loop A and the cooling liquid of the battery cooling system flows through a loop C by switching the three-way valve and the four-way valve; the motor is in a heating mode, the cooling liquid of the motor driving system flows through a loop B by switching the three-way valve and the four-way valve, and the purpose that the cooling liquid heated by the motor driving system flows to the battery pack cooling loop to heat the battery is achieved.

The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. The cooperative control method of the energy conversion device is characterized in that the energy conversion device comprises a reversible PWM rectifier, a motor coil, a power switch module and an inductor, the reversible PWM rectifier is connected with the motor coil, the positive terminal of an external battery is connected with a first bus end of the reversible PWM rectifier and a first end of the power switch module, the negative terminal of the external battery is connected with a second bus end of the reversible PWM rectifier and a second end of the power switch module, a third end of the power switch module is connected with a first end of the inductor, and a first end and a second end of an external charging and discharging port are respectively connected with a second end of the inductor and a second end of the power switch module;

the cooperative control method comprises the following steps:

2. The cooperative control method according to claim 1, wherein said obtaining a first heating power of the motor coil based on the first quadrature axis current and the first direct axis current further comprises:

when the deviation between the first heating power and the target heating power is within a preset range, setting the first quadrature-axis current and the first direct-axis current as a target quadrature-axis current and a target direct-axis current.

3. The cooperative control method according to claim 2, wherein when the target charge-discharge power is zero and the target charge-discharge current is zero, the cooperative control method comprises:

acquiring target heating power and target driving power;

acquiring a first quadrature axis current and a first direct axis current according to the target driving power, and acquiring a first heating power of the motor coil according to the first quadrature axis current and the first direct axis current;

setting the first quadrature-axis current and the first direct-axis current as a target quadrature-axis current and a target direct-axis current when a deviation between the first heating power and the target heating power is within a preset range;

acquiring a sampling current value and a motor rotor position on each phase of coil, and calculating the duty ratio of each phase of bridge arm in the reversible PWM rectifier according to a target quadrature axis current, a target direct axis current, the sampling current value on each phase of coil and the motor rotor position;

or, when the target heating power is zero, the cooperative control method includes:

acquiring target charge-discharge power and target driving power;

acquiring target charge-discharge current output by the external charge-discharge port according to the target charge-discharge power;

acquiring a first quadrature-axis current and a first direct-axis current according to the target driving power, and setting the first quadrature-axis current and the first direct-axis current as a target quadrature-axis current and a target direct-axis current;

acquiring a sampling current value and a motor rotor position on each phase coil, calculating the duty ratio of each phase bridge arm in the reversible PWM rectifier according to a target quadrature axis current, a target direct axis current, the sampling current value on each phase coil and the motor rotor position, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the charging and discharging current sampling value;

or, when the target driving power is zero, the cooperative control method includes:

acquiring target heating power and target charge-discharge power;

obtaining a target quadrature axis current and a target direct axis current according to the target heating power;

the method comprises the steps of obtaining a sampling current value, a charging and discharging current sampling value and a rotor electric angle on each phase of coil, calculating the duty ratio of each phase of bridge arm in the reversible PWM rectifier according to a target quadrature axis current, a target direct axis current, a target charging and discharging current, a sampling current value on each phase of coil and a rotor electric angle of a motor on the position of the motor rotor, and calculating the duty ratio of the bridge arm in the power switch module according to the target charging and discharging current and the charging and discharging current sampling value.

4. The cooperative control method according to claim 1 or 2, wherein the obtaining of the target charge-discharge current output from the external charge-discharge port according to the target charge-discharge power includes:

when the external power supply connected to the external charging and discharging port is in a constant-current charging and discharging mode, acquiring the target voltage of an external battery according to the target charging and discharging power;

acquiring actual voltage of a charge-discharge port, and acquiring a voltage difference value according to the target voltage and the actual voltage of the charge-discharge port;

performing closed-loop control on the voltage difference value to obtain target charging and discharging current output to an inductor;

or, when the external power supply connected to the external charging and discharging port is in a constant voltage charging and discharging mode, obtaining the current of the external charging and discharging port according to the target charging and discharging power as the target charging and discharging current output by the external charging and discharging port.

5. The cooperative control method according to claim 1 or 2, wherein the obtaining of the first quadrature axis current and the first direct axis current in the synchronous rotating coordinate system based on the motor rotor magnetic field orientation according to the target driving power comprises:

and performing table lookup in a preset torque curve graph according to the torque output command to obtain a first quadrature axis current and a first direct axis current.

6. The cooperative control method according to claim 1 or 2, wherein the adjusting the first quadrature-axis current and the first direct-axis current to a target quadrature-axis current and a target direct-axis current according to the target driving power so that a deviation between the first heating power and the target heating power is within a preset range comprises:

and performing table lookup in a preset torque curve chart to obtain another set of quadrature axis current and direct axis current until the deviation between the first heating power and the target heating power is within a preset range.

7. The cooperative control method according to claim 4, wherein the calculating a duty ratio of each phase leg in the reversible PWM rectifier according to a target quadrature-axis current, a target direct-axis current, a sampled current value on each phase coil, and a motor rotor position, and calculating a duty ratio of a leg in the power switching module according to the target charging and discharging current and the sampled charging and discharging current value comprises:

acquiring actual quadrature axis current and actual direct axis current of each set of windings according to the sampling current value of each phase coil and the position of the motor rotor;

respectively performing closed-loop control according to the target quadrature-axis current and the actual quadrature-axis current, and the target direct-axis current and the actual direct-axis current to obtain a direct-axis reference voltage and a quadrature-axis reference voltage, and obtaining the duty ratio of each phase of bridge arm according to the direct-axis reference voltage, the quadrature-axis reference voltage and the position of the motor rotor;

and carrying out closed-loop control according to the target charging and discharging current and the charging and discharging current sampling value to obtain the duty ratio of a bridge arm in the power switch module.

8. The cooperative control method according to claim 7, wherein said obtaining an actual quadrature-axis current and an actual direct-axis current from the sampled current value on the coil of each phase and the motor rotor position comprises:

carrying out clark coordinate transformation on the sampling current value of each phase coil to obtain a current value of a static coordinate system;

and carrying out park coordinate transformation according to the current value of the static coordinate system and the position of the motor rotor to obtain actual quadrature-axis current and actual direct-axis current.

9. The cooperative control method according to claim 7, wherein the obtaining of the direct-axis reference voltage and the quadrature-axis reference voltage by performing the closed-loop control according to the target quadrature-axis current and the actual quadrature-axis current, the target direct-axis current and the actual direct-axis current respectively comprises:

calculating the target quadrature axis current and the actual quadrature axis current to obtain a quadrature axis current difference value, and calculating the target direct axis current and the actual direct axis current to obtain a direct axis current difference value;

respectively controlling the quadrature axis current difference and the direct axis current difference to obtain quadrature axis reference voltage and direct axis reference voltage;

acquiring the duty ratio of each phase of bridge arm according to the direct-axis reference voltage, the quadrature-axis reference voltage and the position of the motor rotor, wherein the duty ratio comprises the following steps:

performing inverse park coordinate transformation on the quadrature axis reference voltage, the direct axis reference voltage and the position of the motor rotor to obtain a voltage of a static coordinate system;

and carrying out space vector modulation conversion on the voltage of the static coordinate system to obtain the duty ratio of each phase of bridge arm.

10. The cooperative control method according to claim 4, wherein the calculating a duty ratio of each phase leg in the reversible PWM rectifier according to a target quadrature-axis current, a target direct-axis current, a sampled current value on each phase coil, and a motor rotor position, and calculating a duty ratio of a leg in the power switching module according to the target charging and discharging current and the sampled charging and discharging current value comprises:

acquiring a target current value of each phase coil according to the target quadrature axis current, the target direct axis current and the position of the motor rotor;

acquiring the reference voltage of each phase of bridge arm according to the sampling current value of each phase of coil and the target current value of each phase of coil;

acquiring the duty ratio of each phase of bridge arm according to the reference voltage of each phase of bridge arm;

11. The cooperative control method according to claim 10, wherein the obtaining of the target current value of each phase coil based on the target quadrature-axis current, the target direct-axis current, and the motor rotor position includes:

and carrying out reverse park and reverse clark coordinate transformation according to the target quadrature axis current, the target direct axis current and the rotor position to obtain a target current value of each phase of coil.

12. The cooperative control method according to claim 4, wherein the calculating a duty ratio of each phase leg in the reversible PWM rectifier according to a target quadrature-axis current, a target direct-axis current, a sampled current value on each phase coil, and a motor rotor position, and calculating a duty ratio of a leg in the power switching module according to the target charging and discharging current and the sampled charging and discharging current value comprises:

acquiring a target alpha-axis current and a target beta-axis current of a motor static coordinate system according to the target quadrature-axis current, the target direct-axis current and the rotor position;

acquiring actual alpha-axis current and actual beta-axis current of a motor static coordinate system according to the sampling current value on each phase coil;

acquiring a reference voltage of a motor coil in a static coordinate system according to the target alpha-axis current, the target beta-axis current, the actual alpha-axis current and the actual beta-axis current;

carrying out space vector modulation conversion on the reference voltage of the static coordinate system to obtain the duty ratio of each phase of bridge arm;

13. The cooperative control method according to claim 1, characterized by further comprising:

when the target driving power is converted from a first target driving power to a second target driving power, acquiring a composite current vector amplitude according to a target quadrature-axis current and a target direct-axis current corresponding to the first target driving power;

acquiring a first intersection point coordinate and a second intersection point coordinate which are formed by a circle and a torque curve corresponding to the second target driving power, wherein the circle takes an origin in a preset torque curve as a circle center and the synthetic current vector magnitude as a radius;

respectively acquiring a first distance between the first intersection point coordinate and a coordinate point formed by the target quadrature axis current and the target direct axis current and a second distance between the second intersection point coordinate and a coordinate point formed by the target quadrature axis current and the target direct axis current;

and determining the intersection point coordinate corresponding to the smaller value of the first distance and the second distance as the target direct axis current and the target quadrature axis current of the second target driving power.

14. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the steps of the method according to any one of claims 1 to 13.

15. The cooperative control device of the energy conversion device is characterized in that the energy conversion device comprises a reversible PWM rectifier, a motor coil, a power switch module and an inductor, wherein the reversible PWM rectifier is connected with the motor coil, the positive terminal of an external battery is connected with a first bus end of the reversible PWM rectifier and a first end of the power switch module, the negative terminal of the external battery is connected with a second bus end of the reversible PWM rectifier and a second end of the power switch module, a third end of the power switch module is connected with a first end of the inductor, and a first end and a second end of an external charging and discharging port are respectively connected with a second end of the inductor and a second end of the power switch module;

the cooperative control apparatus includes:

16. A vehicle characterized by further comprising the energy conversion apparatus of claim 15.