Control method of modular multi-phase motor for vehicle and driving system thereof, and vehicle

Abstract

The present invention discloses a control method for a modular multi-phase motor for a vehicle, a drive system thereof, and a vehicle. The modular multi-phase motor for a vehicle comprises n independent multi-phase motor units, each of which is driven and controlled by its corresponding independent driver, and each of which is powered by its corresponding independent power supply, and each of which is connected to an on-board computer, respectively. The control method comprises: the on-board computer is pre-installed with an optimal efficiency algorithm, and the number of independent multi-phase motor units required to be operated and their corresponding output powers are calculated according to the power demand of the vehicle and with satisfying the optimal efficiency algorithm as the driving target. The present invention enables the efficiency of the entire drive system to always be in a relatively high level of operation, thereby achieving the purpose of saving electric energy and thereby improving the cruising range of the entire vehicle.

Description

Technical Field

[0001] The present invention belongs to the field of motor control, and specifically relates to a control method for a modular multi-phase motor for a vehicle. The present invention also relates to a drive system adopted by the drive system and a vehicle using the same. Background Art

[0002] In the field of electric vehicle drive control, the topology of the drive motor system is mostly a centralized power supply topology, in which the motor is powered by a single driver and a single power source (i.e., battery). Due to the complex actual operating conditions of electric vehicles, single-motor systems often operate in low-efficiency areas, resulting in shorter driving mileage. In addition, the battery pack is integrated into one piece, which is too large, which not only limits the flexibility of the vehicle's spatial layout and the weight configuration of the chassis, but also local failures of the battery will spread to the entire battery pack, expanding the failure loss and even causing an explosion. The centralized power supply topology system has poor fault tolerance. If any of the three parts, the power supply, driver, or motor, has a local failure, the system will not work, causing the vehicle to lose power.

[0003] Modular multi-phase motor drive control systems are favored for their flexible control, high power factor, and strong fault tolerance, and have become an important direction for the development of high-power propulsion motor systems at home and abroad. For example, the Chinese patent with publication number CN104518724A discloses a fifteen-phase motor channel control system and control method, and proposes a multi-phase motor channel control method for the first time: the fifteen-phase propulsion system is divided into three channels, and the topology and number of motor windings of each channel are five phases. Each channel includes a switch, a propulsion transformer, an uncontrolled rectifier, a five-phase inverter, and a five-phase motor winding. However, the patent stipulates that the output of the three five-phases is consistent, and does not fully take into account the different temperature rise conditions of each five-phase module, and the power supply mode mentioned in the patent is limited to centralized power supply. Another example is the Chinese patent with publication number CN106787338A, which discloses a multi-phase motor drive system and method with independent power supply of distributed battery group windings. Although the system uses distributed power supply, each phase winding of the motor is connected to a power supply unit separately, and the power supply system is redundant; the Chinese patent with publication number CN106208894A discloses a multi-phase motor drive system, each phase winding of the motor is connected to an H-bridge power unit separately, and the power device is redundant. The Chinese patent with publication number CN106787338A discloses a winding set type multi-phase motor and its control method, the motor includes three sets of armature windings, which are high-speed windings, medium-speed windings and low-speed windings. The three sets of armature windings have the same rated power and different rated speeds; the neutral points of the three sets of armature windings are independently led out; the motor is controlled by a main controller and three sub-controllers, which are high-speed controllers, medium-speed controllers and low-speed controllers, respectively, to control the working states of high-speed windings, medium-speed windings and low-speed windings, so that the motor drives the load to rotate under the optimal efficiency state. Although this system achieves high-efficiency operation of the motor, the motor winding specifications are inconsistent, which increases the difficulty of processing; the operating conditions of the three sets of windings are inconsistent, resulting in large differences in the temperature rise states and lifespans of different windings.

[0004] Therefore, the inventor of the present application decided to propose a new technical solution based on his dedicated R&D experience and accumulated theoretical knowledge in this field. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a control method for a modular multi-phase motor for a vehicle, a drive system, and a vehicle, so that the efficiency of the entire drive system is always at a high level, thereby achieving the purpose of saving electric energy and further improving the cruising range of the vehicle.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A control method for a modular multi-phase motor for a vehicle, the modular multi-phase motor for a vehicle comprising n independent multi-phase motor units, each independent multi-phase motor unit being driven and controlled by its corresponding independent driver, and each independent driver being powered by its corresponding independent power supply, each independent multi-phase motor unit, each independent driver and each independent power supply being connected to an on-board computer respectively; wherein the control method comprises: the on-board computer is pre-installed with an optimal efficiency algorithm, and the number of independent multi-phase motor units required to be operated and their corresponding output powers are calculated according to the power demand of the vehicle and with satisfying the optimal efficiency algorithm as the driving target.

[0008] Preferably, the method comprises the following steps:

[0009] S10), the onboard computer obtains the power demand of the vehicle;

[0010] S20), according to the motor efficiency cloud map and the driver efficiency cloud map preset in the vehicle computer, the vehicle computer calculates the optimal efficiency operating point of each independent multi-phase motor unit and its independent driver, and uses this as the optimal efficiency algorithm;

[0011] S30), based on the optimal efficiency algorithm, calculating the number of independent multi-phase motor units required to be operated and their corresponding output powers to meet the power demand of the vehicle;

[0012] S40), allocating the power demand of the vehicle to a corresponding number of independent multi-phase motor units, and the corresponding number of independent multi-phase motor units perform power operation.

[0013] Preferably, in the step S40), when the calculated number of independent multi-phase motor units required to be run is greater than or equal to the number of independent multi-phase motor units, all independent multi-phase motor units need to be run simultaneously; when the calculated number of independent multi-phase motor units required to be run is less than the number of independent multi-phase motor units, at least one independent multi-phase motor unit should be in an idle state.

[0014] Preferably, the step S40) is allocated based on an optimal allocation algorithm, wherein the optimal allocation algorithm includes: based on the real-time temperature of each independent multi-phase motor unit and the real-time charge of its corresponding independent power supply, an optimal allocation calculation is performed to obtain the temperature rise balance of each independent multi-phase motor unit and the charge balance of its corresponding independent power supply as the control target.

[0015] Preferably, in the optimal allocation algorithm, the independent multi-phase motor unit with a lower temperature and a higher charge of the corresponding independent power supply is preferentially operated as a power output module, and the independent multi-phase motor unit with a higher temperature and a lower charge of the corresponding independent power supply is set to an idle state.

[0016] Preferably, taking into account that with the increase of running time, the temperature of the independent multi-phase motor units in the running state increases and the charge of their corresponding independent power supplies decreases, wherein, in the optimal allocation algorithm, the on-board computer evaluates the independent multi-phase motor units in the running state and the remaining independent multi-phase motor units in the idle state based on the real-time temperature of each independent multi-phase motor unit and the real-time charge of its corresponding independent power supply, and the optimal allocation algorithm switches one or more independent multi-phase motor units in the idle state into the running state to replace the corresponding number of independent multi-phase motor units in the running state.

[0017] Preferably, the power output of the independent multi-phase motor unit in the running state is set to a high-level signal, and the power output of the independent multi-phase motor unit in the idle state is set to a low-level signal, so that the power output states of all independent multi-phase motor units are distributed in a pulse width modulation pattern.

[0018] Preferably, a drive system for a modular multi-phase motor for a vehicle, the drive system includes a modular multi-phase motor for a vehicle, the modular multi-phase motor for a vehicle includes n independent multi-phase motor units, each independent multi-phase motor unit is driven and controlled by its corresponding independent driver, and each independent driver is powered by its corresponding independent power supply, each independent multi-phase motor unit, each independent driver and each independent power supply is connected to an on-board computer respectively; wherein the drive system adopts the control method as described above.

[0019] Preferably, the modular multi-phase motor for the vehicle adopts a fractional-slot concentrated winding motor, and the independent multi-phase motor unit is an independent three-phase motor unit or an independent five-phase motor unit or an independent other multi-phase motor unit; the on-board computer respectively collects the real-time temperature of each independent multi-phase motor unit and the real-time charge of its corresponding independent power supply in real time.

[0020] Preferably, a vehicle adopts the drive system as described above.

[0021] The present application pre-sets the optimal efficiency algorithm in the on-board computer, calculates the number of independent multi-phase motor units required to be operated and their corresponding output power according to the power demand of the vehicle and taking the optimal efficiency algorithm as the driving target, and the corresponding number of independent multi-phase motor units performs power operation, so that the modular multi-phase motor of the vehicle is kept in the high-efficiency zone, and the unit motor that is not working is directly cut to the idle state without generating driver loss, so that the efficiency of the entire drive system is always in a high-level operation state, achieving the purpose of saving electric energy, and thus improving the cruising range of the whole vehicle; and the present application especially proposes a regular distribution control method of pulse width modulation based on the optimal allocation algorithm, which not only ensures the balance and state consistency among the independent power supply, the independent driver and its corresponding independent multi-phase motor unit, but also each independent multi-phase motor unit will not run in a full-load state for a long time, and the temperature rise only occurs during the on time, and the independent multi-phase motor unit during the off time (in the idle state) can be well cooled, which effectively extends the life of each independent multi-phase motor unit. In addition, since the charge state of the independent power supply is in a dynamic equilibrium state, the present application also effectively extends the life of the independent power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of a drive system of a modular multi-phase motor for a vehicle according to a specific embodiment of the present invention;

[0023] Figure 2 It is a flowchart of a control method for a modular multi-phase motor for a vehicle according to a specific embodiment of the present invention;

[0024] Figure 3 It is a schematic diagram of the communication structure of the vehicle-mounted computer under a specific implementation mode of the present invention. DETAILED DESCRIPTION

[0025] An embodiment of the present invention discloses a control method for a modular multi-phase motor for a vehicle. The modular multi-phase motor for a vehicle includes n independent multi-phase motor units, each independent multi-phase motor unit is driven and controlled by its corresponding independent driver, and each independent driver is powered by its corresponding independent power supply, and each independent multi-phase motor unit, each independent driver and each independent power supply are connected to an on-board computer respectively; wherein the control method includes: the on-board computer is pre-installed with an optimal efficiency algorithm, and the number of independent multi-phase motor units required to be operated and their corresponding output powers are calculated according to the power demand of the vehicle and with satisfying the optimal efficiency algorithm as the driving target.

[0026] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0027] Example 1: Please see Figure 1 As shown, the present embodiment provides a vehicle modular three-phase motor drive system, which specifically includes a vehicle modular three-phase motor having n independent three-phase motor units, n independent drivers, n independent power supplies and a single vehicle-mounted computer, wherein each independent three-phase motor unit is driven and controlled by its corresponding independent driver, and each independent driver is powered by its corresponding independent power supply, and each independent three-phase motor unit, each independent driver and each independent power supply are connected to the vehicle-mounted computer respectively;

[0028] In this embodiment, the modular three-phase motor for a vehicle adopts a fractional slot concentrated winding motor; the kth independent three-phase motor unit works, the three-phase winding of the kth independent three-phase motor unit is arranged in its corresponding fixed kth stator sector, the kth independent driver is only used to drive the kth independent three-phase motor unit, and the kth independent power supply is only used to power the kth independent driver, wherein 1≤k≤n, n, k are positive integers greater than 1;

[0029] In this embodiment, the on-board computer collects the real-time temperature of n independent three-phase motor units and the real-time charge of n independent power supplies in real time, and the on-board computer is pre-installed with a motor efficiency cloud map (specifically including a motor speed-torque efficiency map) and a driver efficiency cloud map. In actual applications, an AI algorithm can be used to obtain the motor efficiency cloud map and the driver efficiency cloud map.

[0030] The drive system in this embodiment adopts the following control method. The on-board computer is preset with an optimal efficiency algorithm. According to the power demand of the vehicle and taking the optimal efficiency algorithm as the driving target, the number of independent three-phase motor units required to run and their corresponding output power are calculated. Please refer to Figure 2 Combined with Figure 3 As shown, the following steps are included:

[0031] S10), the on-board computer collects and obtains the power demand of the vehicle;

[0032] S20), according to the motor efficiency cloud map and the driver efficiency cloud map, the on-board computer calculates the optimal efficiency operating point of each independent three-phase motor unit and its independent driver, and uses this as the optimal efficiency algorithm;

[0033] S30). Based on the optimal efficiency algorithm, calculate the number m (m < n) of independent three-phase motor units to be operated and their corresponding output powers Pj (1 ≤ j ≤ m) to meet the power demand of the vehicle.

[0034] S40). Allocate the power demand of the vehicle to the corresponding number m of independent three-phase motor units based on the optimal allocation algorithm, and the corresponding number m of independent three-phase motor units perform power operation; preferably, in this step S40), the calculated number m of independent three-phase motor units to be operated is less than the number n of independent three-phase motor units, and at least one independent three-phase motor unit is in a vacant state; specifically preferably, in this embodiment, the optimal allocation algorithm includes: taking the temperature rise balance of each independent three-phase motor unit (n units) and the charge balance of its corresponding independent power source (n units) as the control target for optimal allocation calculation based on the real-time temperature of each independent three-phase motor unit and the real-time charge of its corresponding independent power source. The preferred optimal allocation calculation principle adopted is: give priority to operating the independent three-phase motor unit with a lower temperature and a higher charge of its corresponding independent power source as the power output module, and set the independent three-phase motor unit with a higher temperature and a lower charge of its corresponding independent power source to a vacant state.

[0035] Further preferably, considering that as the operation time increases, the temperature of the m independent three-phase motor units in the operating state rises, and the charge of their corresponding independent power sources (m units) decreases. Among them, in the optimal allocation algorithm, the in-vehicle computer evaluates the m independent three-phase motor units in the operating state and the remaining (n - m) independent three-phase motor units in the vacant state according to the real-time temperature of each independent three-phase motor unit (n units) and the real-time charge of its corresponding independent power source (n units). The optimal allocation algorithm switches l (0 <= l <= n - m) independent three-phase motor units in the vacant state to the operating state to replace the corresponding number (l units) of independent three-phase motor units in the operating state.

[0036] In this embodiment, set the power output of the independent three-phase motor unit in the operating state to a high-level signal, and set the power output of the independent three-phase motor unit in the vacant state to a low-level signal, so that the power output states of all independent three-phase motor units are distributed according to the rule of pulse width modulation, and the in-vehicle computer sends this pulse width modulation signal as an instruction to each independent driver to achieve the cyclic power output of its corresponding independent three-phase motor unit.

[0037] Embodiment 2: The rest of the technical solutions of this embodiment 2 are the same as those of embodiment 1, with the difference being that, in this embodiment 2, the number m of independent three-phase motor units required to be run is calculated to be greater than or equal to the number n of independent three-phase motor units, and all independent three-phase motor units need to run simultaneously, that is, the power outputs of all independent three-phase motor units (n) are set to high-level signals, presenting a regular distribution of pulse width modulation with a duty cycle of 100%, so that the on-board computer sends the pulse width modulation signal as a command to each independent driver, thereby realizing the cyclic power output of the corresponding independent three-phase motor unit.

[0038] Example 3: The rest of the technical solutions of Example 3 are the same as those of Example 1 or Example 2, except that, in Example 3, the modular three-phase motor for vehicles is replaced by a modular five-phase motor for vehicles, and n independent five-phase motor units are provided; in other implementation modes, the modular three-phase motor for vehicles can also be replaced by other numbers of modular multi-phase motors for vehicles, and this example does not make any special and unique limitation on it.

[0039] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0040] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A control method for a modular multi-phase motor for a vehicle, characterized in that: The modular multi-phase motor for a vehicle comprises n independent multi-phase motor units, each independent multi-phase motor unit is driven and controlled by its corresponding independent driver, and each independent driver is powered by its corresponding independent power supply, and each independent multi-phase motor unit, each independent driver and each independent power supply are connected to an on-board computer respectively; wherein, the control method comprises: the on-board computer is pre-installed with an optimal efficiency algorithm, and the number of independent multi-phase motor units required to be operated and their corresponding output powers are calculated according to the power demand of the vehicle and with satisfying the optimal efficiency algorithm as a driving target; the following steps are included: S10), the onboard computer obtains the power demand of the vehicle; S20), according to the motor efficiency cloud map and the driver efficiency cloud map preset in the vehicle computer, the vehicle computer calculates the optimal efficiency operating point of each independent multi-phase motor unit and its independent driver, and uses this as the optimal efficiency algorithm; S30), based on the optimal efficiency algorithm, calculating the number of independent multi-phase motor units required to be operated and their corresponding output powers to meet the power demand of the vehicle; S40), allocating the power demand of the vehicle to a corresponding number of independent multi-phase motor units, and the corresponding number of independent multi-phase motor units perform power operation.

2. The control method according to claim 1, characterized in that: In the step S40), when the calculated number of independent multi-phase motor units required to be run is greater than or equal to the number of independent multi-phase motor units, all independent multi-phase motor units need to be run simultaneously; when the calculated number of independent multi-phase motor units required to be run is less than the number of independent multi-phase motor units, at least one independent multi-phase motor unit should be in an idle state.

3. The control method according to claim 2, characterized in that: The step S40) is allocated based on an optimal allocation algorithm, wherein the optimal allocation algorithm includes: based on the real-time temperature of each independent multi-phase motor unit and the real-time charge of its corresponding independent power supply, an optimal allocation calculation is performed to obtain the temperature rise balance of each independent multi-phase motor unit and the charge balance of its corresponding independent power supply as a control target.

4. The control method according to claim 3, characterized in that: In the optimal allocation algorithm, independent multi-phase motor units with lower temperatures and higher charges of corresponding independent power supplies are preferentially operated as power output modules, and independent multi-phase motor units with higher temperatures and lower charges of corresponding independent power supplies are set to an idle state.

5. The control method according to claim 3, characterized in that: Taking into account that as the running time increases, the temperature of the independent multi-phase motor units in the running state increases and the charge of their corresponding independent power supplies decreases, wherein, in the optimal allocation algorithm, the on-board computer evaluates the independent multi-phase motor units in the running state and the remaining independent multi-phase motor units in the idle state based on the real-time temperature of each independent multi-phase motor unit and the real-time charge of its corresponding independent power supply. The optimal allocation algorithm switches one or more independent multi-phase motor units in the idle state into the running state to replace the corresponding number of independent multi-phase motor units in the running state.

6. The control method according to claim 2, 4 or 5, characterized in that: The power output of the independent multi-phase motor unit in the running state is set to a high level signal, and the power output of the independent multi-phase motor unit in the idle state is set to a low level signal, so that the power output state of all independent multi-phase motor units is distributed according to the pulse width modulation rule.

7. A modular multi-phase motor drive system for a vehicle, characterized in that: The drive system includes a modular multi-phase motor for a vehicle, and the modular multi-phase motor for a vehicle includes n independent multi-phase motor units, each independent multi-phase motor unit is driven and controlled by its corresponding independent driver, and each independent driver is powered by its corresponding independent power supply, and each independent multi-phase motor unit, each independent driver and each independent power supply are respectively connected to an on-board computer; wherein, the drive system adopts the control method as described in any one of claims 1-6.

8. The drive system according to claim 7, characterized in that: The modular multi-phase motor for the vehicle adopts a fractional-slot concentrated winding motor, and the independent multi-phase motor unit is an independent three-phase motor unit or an independent five-phase motor unit or an independent other multi-phase motor unit; the on-board computer collects the real-time temperature of each independent multi-phase motor unit and the real-time charge of its corresponding independent power supply in real time.

9. A vehicle, characterized in that: A drive system as claimed in claim 7 or 8 is used.

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