Boost control method and system of dual-motor power system

Abstract

The invention discloses a boost control method and system for a dual-motor power system. The boost control method comprises the following steps: calibrating a first electric drive to obtain first electric drive calibration data; calibrating a second electric drive to obtain second electric drive calibration data; generating electric drive total power loss calibration data according to the first electric drive calibration data and the second electric drive calibration data; calibrating the voltage booster to obtain voltage booster calibration data; generating system power loss calibration data according to the booster calibration data and the electric drive total power loss calibration data; real-time electric drive parameters are obtained, calibration electric drive parameters corresponding to the real-time electric drive parameters in the system power loss calibration data are determined, and the calibration electric drive parameters are the minimum sum of absolute values of difference values between the calibration electric drive parameters and the real-time electric drive parameters in the system power loss calibration data; the boost corresponding to the minimum system power loss of the calibrated electric drive parameter is the target boost.

Description

Technical Field

[0001] The present invention relates to the technical field of real-time boost control of a dual-motor power system, and in particular to a boost control method and system for a dual-motor power system. Background Art

[0002] With the popularization of new energy vehicles and the development of new energy technologies, people have put forward higher requirements for the power, charging time and driving range of the electric drive system that provides power for vehicles. High voltage platform technology provides a basis for improving the power of the electric drive system. Under high voltage, the electric drive system can output greater power under the same current carrying capacity, thereby improving the performance of the whole vehicle.

[0003] The prior art adopts a method of boosting a fixed target voltage with a booster to provide a high voltage for the electric drive, or does not adopt a booster, and the power battery provides energy for the electric drive without voltage boosting. Summary of the invention

[0004] To solve at least one aspect of the above problems, the present invention provides a boost control method for a dual-motor power system, including: calibrating the first electric drive to obtain first electric drive calibration data, the first electric drive calibration data including the boost, first current and first electric drive power loss corresponding to the first torque and first speed of the first electric drive; calibrating the second electric drive to obtain second electric drive calibration data, the second electric drive calibration data including the second torque and second speed and the boost, second current and second electric drive power loss corresponding to the second electric drive; generating electric drive total power loss calibration data based on the first electric drive calibration data and the second electric drive calibration data, the electric drive total power loss calibration data including the total electric drive power loss, boost and total electric drive current corresponding to the first torque, first speed, second torque and second speed, the total electric drive power loss is equal to the sum of the first electric drive power loss and the second electric drive power loss; calibrating the booster to obtain Booster calibration data, the booster calibration data including boost and boost power loss corresponding to the total electric drive current; generating system power loss calibration data according to the booster calibration data and the total electric drive power loss calibration data, the system power loss calibration data including the boost and system power loss corresponding to the first speed, the first torque, the second speed and the second torque, the system power loss being equal to the sum of the total electric drive power loss and the booster power loss; acquiring real-time electric drive parameters, the real-time electric drive parameters including the real-time first speed, the real-time first torque, the real-time second speed and the real-time second torque, determining the calibrated electric drive parameters corresponding to the real-time electric drive parameters in the system power loss calibration data, the calibrated electric drive parameters being the sum of the absolute values ​​of the differences between the system power loss calibration data and the items of the real-time electric drive parameters being the smallest, and the boost corresponding to the minimum system power loss of the calibrated electric drive parameters being the target boost.

[0005] Preferably, the step of calibrating the first electric drive to obtain the first electric drive calibration data also includes: setting the first torque and the first speed according to a preset speed interval and a preset torque interval, sequentially recording the first current corresponding to the first torque and the first speed under different boosts, and calculating the first electric drive power loss based on the first torque, the first speed, the boost and the first current.

[0006] Preferably, the preset speed interval is 500 rpm, and the preset torque interval is 10 Nm.

[0007] Preferably, the step of calibrating the second electric drive to obtain second electric drive calibration data also includes: setting the second torque and the second speed according to a preset speed interval and a preset torque interval, sequentially recording the second current corresponding to the second torque and the second speed under different boosts, and calculating the second electric drive power loss based on the second torque, the second speed, the boost and the second current.

[0008] Preferably, the preset speed interval is 500 rpm, and the preset torque interval is 10 Nm.

[0009] On the other hand, a boost control system of a dual-motor power system is provided, comprising: a data acquisition unit and a boost control unit, wherein the data acquisition unit is used to obtain real-time electric drive parameters, and the boost control unit adopts a boost control method of the dual-motor power system as described in any of the above based on the real-time electric drive parameters.

[0010] The boost control method and system of the dual-motor power system of the embodiment of the present invention have the following beneficial effects: The provided technical solution may include the following beneficial effects: using a booster to boost the system can provide a larger power range for the electric drive system and provide power for the entire vehicle; using a variable boost control method, it can be combined with real-time calculation according to the current driving needs of the entire vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to better understand the above and other purposes, features, advantages and functions of the present invention, reference may be made to the embodiments shown in the accompanying drawings. The same reference numerals in the accompanying drawings refer to the same components. It should be understood by those skilled in the art that the accompanying drawings are intended to schematically illustrate the preferred embodiments of the present invention and have no limiting effect on the scope of the present invention, and the components in the drawings are not drawn to scale.

[0012] Figure 1 A flowchart of a voltage boost control method for a dual-motor power system according to an embodiment of the present invention is shown;

[0013] Figure 2 A structural block diagram of a boost control system of a dual-motor power system according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0014] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0015] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0016] In order to at least partially solve one or more of the above problems and other potential problems, an embodiment of the present disclosure provides a boost control method for a dual-motor power system, wherein the dual-motor power system includes a battery, a booster, a first electric drive and a second electric drive, such as Figure 2 As shown, the battery is connected to the electric drive 1 (first electric drive) and the electric drive 2 (second electric drive) through the booster. The battery is connected to the low-voltage side of the booster. The initial voltage output by the battery is U L After the booster is boosted, the voltage on the boost side of the booster increases to U H The high-voltage side of the booster is connected to both electric drive 1 and electric drive 2.

[0017] like Figure 1 As shown, the boost control method of the dual-motor power system includes: calibrating the first electric drive to obtain first electric drive calibration data, the first electric drive calibration data including the boost corresponding to the first torque and first speed of the first electric drive, the first current and the first electric drive power loss.

[0018] Specifically, the step of calibrating the first electric drive to obtain the first electric drive calibration data also includes: setting the first torque and the first speed according to a preset speed interval and a preset torque interval, sequentially recording the first current corresponding to the first torque and the first speed under different boosts, and calculating the first electric drive power loss based on the first torque, the first speed, the boost and the first current.

[0019] In some embodiments, the preset speed interval is 500 rpm, and the preset torque interval is 10 Nm. Those skilled in the art will appreciate that in other embodiments, the preset speed interval and preset torque interval set by calibration can be set according to actual needs.

[0020] The first electric drive calibration data includes the following: H (For example, U H =300V, 600V, 800V…) To achieve the first torque, first speed combination [T1, ω1], the corresponding boost and first current combination [U H , I1], and calculate the first electric drive power loss P of the electric drive 1 under this condition 损1 ,in,

[0021]

[0022] An example of the first electric drive calibration data is as follows:

[0023] 300V:

[0024]

[0025] 600V:

[0026]

[0027] 800V:

[0028]

[0029] The second electric drive is calibrated to obtain second electric drive calibration data, where the second electric drive calibration data includes a second torque and a second speed and a boost, a second current, and a second electric drive power loss corresponding to the second electric drive.

[0030] Specifically, the step of calibrating the second electric drive to obtain the second electric drive calibration data further includes: setting the second torque and the second speed according to the preset speed interval and the preset torque interval, sequentially recording the second current corresponding to the second torque and the second speed under different boosts, and calculating the second electric drive power loss according to the second torque, the second speed, the boost and the second current. In some embodiments, the preset speed interval is 500 rpm and the preset torque interval is 10 Nm.

[0031] The second electric drive calibration data includes the following: H (For example, U H =300V, 600V, 800V…) To achieve the second torque and second speed combination [T2, ω2], the corresponding boost and second current combination [U H , I2], and calculate the second electric drive power loss P of electric drive 2 under this condition 损2 ,in,

[0032]

[0033] The electric drive total power loss calibration data is generated based on the first electric drive calibration data and the second electric drive calibration data. The electric drive total power loss calibration data includes the electric drive total power loss corresponding to the first torque, the first speed, the second torque and the second speed, the boost, and the electric drive total current. The electric drive total power loss is equal to the sum of the first electric drive power loss and the second electric drive power loss.

[0034] Specifically, calculate the total electric drive current I of electric drive 1 and electric drive 2 H And the total power loss P of electric drive 1 and electric drive 2 损12 Among them, I H =I1+I2,P 损12 =P 损1 +P 损2 An example of summarizing the calibration data of the first electric drive and the second electric drive is as follows:

[0035] 300V:

[0036]

[0037] 600V:

[0038]

[0039] 800V:

[0040]

[0041] The booster is calibrated to obtain booster calibration data, where the booster calibration data includes booster power loss corresponding to the boost voltage and the total electric drive current.

[0042] Specifically, the booster is matched and calibrated to obtain [U H , I H ], booster power loss P 升损 The power loss of the booster is equal to the input power on the low voltage side of the booster (U L *I L ) and the output power of the high voltage side of the booster (U H *I H ), the voltage and current on both sides of the booster are measured during the calibration process. An example of booster calibration data is as follows:

[0043] 300V:

[0044] <![CDATA[I h ]]> 0 10 20 30 40 …… <![CDATA[P 升损 ]]>

[0045] 600V:

[0046] <![CDATA[I h ]]> 0 10 20 30 40 …… <![CDATA[P 升损 ]]>

[0047] 800V:

[0048] <![CDATA[I H ]]> 0 10 20 30 40 …… <![CDATA[P 升损 ]]>

[0049] The system power loss calibration data is generated according to the boost calibration data and the electric drive total power loss calibration data. The system power loss calibration data includes the boost and system power loss corresponding to the first speed, the first torque, the second speed, and the second torque. The system power loss is equal to the sum of the electric drive total power loss and the boost power loss.

[0050] Specifically, according to the boost voltage and total electric drive current in the electric drive total power loss calibration data, the system power loss corresponding to the boost voltage and total electric drive current is found from the booster calibration data, and the system power loss under different voltages U H Under this condition, electric drive 1 and electric drive 2 need to achieve the system power loss P corresponding to the torque and speed combination [T1, ω, T2, ω2] 损 , where P 损 =P 损12 +P 升损 An example of system power loss calibration data is as follows:

[0051] 300V:

[0052]

[0053] 600V:

[0054]

[0055] 800V:

[0056]

[0057] Acquire real-time electric drive parameters, which include a real-time first speed, a real-time first torque, a real-time second speed, and a real-time second torque; determine calibrated electric drive parameters corresponding to the real-time electric drive parameters in the system power loss calibration data; the calibrated electric drive parameters are the ones in which the sum of the absolute values ​​of the differences between the system power loss calibration data and the real-time electric drive parameters is the smallest; and the boost corresponding to the minimum system power loss of the calibrated electric drive parameters is the target boost.

[0058] Specifically, the real-time electric drive parameters obtained are counted as [T1', ω1', T2', ω2']. The real-time electric drive parameters are calculated with each group of electric drive parameters [T1, ω1, T2, ω2] in the system power loss calibration data to determine the calibrated electric drive parameters, that is, each group of electric drive parameters in the system power loss calibration data is substituted into the formula for calculation. The formula is k1(|T1'-T1|+|T2'-T2|)+k2(|ω1'-ω1|+|ω2'-ω2|), where k1 and k2 are user-defined influencing factors. The group of electric drive parameters with the smallest value obtained by the formula is the calibrated electric drive parameters. It can be seen from the aforementioned system power loss calibration data that a group of electric drive parameters [T1, ω1, T2, ω2] corresponds to multiple combinations of boost and system power loss. The group with the smallest system power loss value is selected from each combination, and the boost value in this group is used as the target boost.

[0059] In another embodiment, the optimal system power loss data can also be generated based on the system power loss calibration data, that is, according to the multiple boost and system power loss combinations corresponding to the same electric drive parameters [T1, ω1, T2, ω2] in the system power loss calibration data, a group with the smallest system power loss value is selected to generate the optimal system power loss data. Then, after obtaining the real-time electric drive parameters, it is only necessary to determine the target electric drive parameters, and then the corresponding target boost can be determined by looking up the table according to the target electric drive parameters. It can be understood by those skilled in the art that the influencing factors k1 and k2 of the formula k1(|T1'-T1|+|T2'-T2|)+k2(|ω1'-ω1|+|ω2'-ω2|) are equal to 1, or, in other embodiments, are set according to the actual electric drive characteristics and calibration results.

[0060] On the other hand, a boost control system of a dual-motor power system is provided, including: a data acquisition unit and a boost control unit, the data acquisition unit is used to obtain real-time electric drive parameters, and the boost control unit adopts a boost control method of any of the previous dual-motor power systems based on the real-time electric drive parameters.

[0061] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the present invention.

Claims

1. A voltage boost control method for a dual-motor power system, characterized in that: include: Calibrate the first electric drive to obtain first electric drive calibration data, where the first electric drive calibration data includes a boost voltage, a first current, and a first electric drive power loss corresponding to a first torque and a first speed of the first electric drive; Calibrate the second electric drive to obtain second electric drive calibration data, where the second electric drive calibration data includes a second torque and a second speed and a boost, a second current, and a second electric drive power loss corresponding to the second electric drive; Generate electric drive total power loss calibration data according to the first electric drive calibration data and the second electric drive calibration data, wherein the electric drive total power loss calibration data includes the electric drive total power loss, boost, and electric drive total current corresponding to the first torque, the first speed, the second torque, and the second speed, and the electric drive total power loss is equal to the sum of the first electric drive power loss and the second electric drive power loss; Calibrate the booster to obtain booster calibration data, wherein the booster calibration data includes booster power loss corresponding to the boost voltage and the total electric drive current; Generate system power loss calibration data according to the booster calibration data and the electric drive total power loss calibration data, wherein the system power loss calibration data includes the boost and system power loss corresponding to the first speed, the first torque, the second speed, and the second torque, and the system power loss is equal to the sum of the electric drive total power loss and the booster power loss; Acquire real-time electric drive parameters, the real-time electric drive parameters including a real-time first speed, a real-time first torque, a real-time second speed, and a real-time second torque; determine calibrated electric drive parameters corresponding to the real-time electric drive parameters in the system power loss calibration data; the calibrated electric drive parameters are those in which the sum of the absolute values ​​of the differences between the system power loss calibration data and each item of the real-time electric drive parameters is the smallest; and the boost corresponding to the minimum system power loss of the calibrated electric drive parameters is the target boost.

2. The method according to claim 1, characterized in that The step of calibrating the first electric drive to obtain the first electric drive calibration data also includes: setting the first torque and the first speed according to the preset speed interval and the preset torque interval, sequentially recording the first current corresponding to the first torque and the first speed under different boosts, and calculating the first electric drive power loss according to the first torque, the first speed, the boost and the first current.

3. The method according to claim 2, characterized in that The preset speed interval is 500 revolutions, and the preset torque interval is 10 Nm.

4. The method according to claim 1, characterized in that: The step of calibrating the second electric drive to obtain the second electric drive calibration data also includes: setting the second torque and the second speed according to the preset speed interval and the preset torque interval, sequentially recording the second current corresponding to the second torque and the second speed under different boosts, and calculating the second electric drive power loss based on the second torque, the second speed, the boost and the second current.

5. The method according to claim 4, characterized in that The preset speed interval is 500 revolutions, and the preset torque interval is 10 Nm.

6. A boost control system for a dual-motor power system, characterized in that: include: A data acquisition unit and a boost control unit, wherein the data acquisition unit is used to obtain real-time electric drive parameters, and the boost control unit adopts the boost control method of the dual-motor power system according to any one of claims 1 to 5 based on the real-time electric drive parameters.

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