Fuel pump, vehicle having the fuel pump, and method for controlling the vehicle

Abstract

The present invention provides an oil pump, a vehicle having the oil pump, and a method for controlling the vehicle. The method for controlling the vehicle includes: detecting the temperature of the oil; detecting the temperature of the drive motor; identifying a target speed of the oil pump corresponding to the detected temperature of the oil and the temperature of the drive motor; when the identified target speed is less than a limit speed, controlling the operation of the oil pump based on the identified target speed; and when the identified target speed is greater than or equal to the limit speed, adjusting the identified target speed based on the temperature gradient of the drive motor in the current time period and the temperature gradient of the drive motor in the previous time period, and controlling the operation of the oil pump based on the adjusted target speed.

Description

[0001] Cross - reference to related applications

[0002] This application is based on and claims the benefit of priority of Korean Patent Application No. 10 - 2020 - 0039724, filed on Apr. 1, 2020 with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical field

[0003] The present invention relates to an oil pump for effectively cooling a drive motor, a vehicle having the oil pump, and a method of controlling the vehicle. More specifically, the present invention relates to an oil pump that adjusts the rotational speed of the oil pump according to the temperature gradient of the motor when the target rotational speed of the oil pump is greater than or equal to the limit rotational speed. Background art

[0004] Vehicles traveling on the road are equipped with various devices for protecting occupants, assisting driving, and enhancing riding comfort.

[0005] Examples of vehicles include motor vehicles (internal combustion engine - driven vehicles) driven by mechanical power generated by burning fuel oil (e.g., gasoline and diesel), and eco - friendly vehicles driven by electricity to reduce harmful fuel emissions and improve fuel efficiency.

[0006] Eco - friendly vehicles include electric vehicles having a rechargeable power source including a battery and a drive motor, where the drive motor rotates using the electricity charged in the battery and drives the wheels using the rotation of the drive motor. Other types of eco - friendly vehicles include hybrid vehicles having an engine, a battery, and a drive motor and driven by controlling the mechanical power of the engine and the power of the drive motor, and hydrogen fuel cell vehicles.

[0007] An electric vehicle has an oil pump for cooling a drive motor, and the oil pump is driven by the temperature of the drive motor.

[0008] The oil pump increases the injection speed of oil, so that as the temperature of the drive motor rises, more oil is injected.

[0009] When increasing the injection speed of oil in response to an increase in the temperature of the drive motor, if the injection speed of oil increases beyond a certain speed, there is a problem that the oil injected after contacting the coil of the drive motor does not flow into the coil of the drive motor, but flows downward along the shape of the coil or bounces off the coil and scatters to the outside of the drive motor.

[0010] Thus, when increasing the injection speed of oil in response to an increase in the temperature of the drive motor, even if a large amount of oil is injected, most of the injected oil is not used for cooling the drive motor, thereby reducing the cooling performance of the drive motor. Summary of the invention

[0011] One aspect of the present invention is to provide an oil pump, a vehicle having the oil pump, and a method of controlling the vehicle, where the oil pump adjusts the rotational speed of the oil pump based on the temperature gradient of the motor when the target rotational speed of the vehicle is greater than or equal to the limit rotational speed.

[0012] Another aspect of the present invention is to provide an oil pump, a vehicle having the oil pump, and a method of controlling the vehicle, where the oil pump obtains a limit rotational speed corresponding to the driving torque of the driving motor, and when the rotational speed of the oil pump is greater than or equal to the obtained limit rotational speed, adjusts the rotational speed of the oil pump based on the temperature gradient of the motor.

[0013] Other aspects of the present invention will be partially described in the following description, and will be partially obvious from the description, or can be learned through the practice of the present invention.

[0014] According to one aspect of the present invention, a vehicle may include: a driving motor connected to wheels, the driving motor configured to apply driving power to the wheels; an oil pump configured to cool the driving motor by supplying oil to the driving motor; a first temperature detector configured to detect the temperature of the oil; a second temperature detector configured to detect the temperature of the driving motor; and a controller configured to identify a target rotational speed of the oil pump corresponding to the detected temperature of the oil and the temperature of the driving motor, and when the identified target rotational speed is greater than or equal to the limit rotational speed, adjust the identified target rotational speed based on the temperature gradient of the driving motor in the current time period and the temperature gradient of the driving motor in the previous time period, and control the operation of the oil pump based on the adjusted target rotational speed.

[0015] The vehicle may further include a memory configured to store the following information as a reference mapping table, the information being related to the target rotational speed that matches in response to the detected temperature of the oil and the temperature of the driving motor. The controller may be configured to identify the target rotational speed through the reference mapping table when the identified target rotational speed is less than the limit rotational speed.

[0016] When the temperature gradient of the driving motor in the current time period is less than the temperature gradient of the driving motor in the previous time period, the controller may be configured to adjust the identified target rotational speed based on a first compensation value.

[0017] The controller may be configured to adjust the identified target rotational speed by adding the identified target rotational speed and the first compensation value.

[0018] When the temperature gradient of the driving motor in the current time period is greater than or equal to the temperature gradient of the driving motor in the previous time period, the controller may be configured to adjust the identified target rotational speed based on a second compensation value.

[0019] The controller can be configured to adjust the identified target speed by subtracting the second compensation value from the identified target speed.

[0020] The vehicle can further include a power converter connected to the battery, the power converter being configured to convert the power stored in the battery into power for driving the drive motor and the oil pump.

[0021] The vehicle can further include: a cooling water receiver configured to supply cooling water; and a heat exchanger disposed adjacent to an oil passage connected to the oil pump and disposed in a cooling water passage of the cooling water receiver, the cooling water receiver being configured to perform heat exchange between the oil and the cooling water.

[0022] The vehicle can further include a filter disposed between the drive motor and the oil pump, the filter being configured to remove impurities from the oil delivered to the oil pump.

[0023] The vehicle can further include: a current detector configured to detect the current flowing through the drive motor; and a speed detector configured to detect the speed of the drive motor. The controller can be configured to obtain the drive torque of the drive motor based on the detected current of the drive motor and the detected speed of the drive motor, to set a limit speed based on a first ratio when the obtained drive torque is greater than or equal to a reference torque, and to set a limit speed based on a second ratio when the obtained drive torque is less than the reference torque.

[0024] According to another aspect of the present invention, the oil pump can include: a driver connected by communicating with a controller provided in the vehicle, the driver being configured to receive power for driving from a power converter provided in the vehicle; a pump motor configured to operate in response to a control command of the driver; and a temperature detector configured to detect the temperature of the oil. The driver can be configured to identify the target speed of the oil pump corresponding to the detected temperature of the oil and the received temperature of the drive motor when receiving the temperature of the drive motor, to adjust the identified target speed based on the temperature gradient of the drive motor in the current time period and the temperature gradient of the drive motor in the previous time period when the identified target speed is greater than or equal to the limit speed, and to control the operation of the pump motor based on the adjusted target speed.

[0025] The oil pump can further include a memory configured to store information related to the target speed matching the detected temperature of the oil and the temperature of the drive motor as a reference mapping table. The controller can be configured to identify the target speed through the reference mapping table when the identified target speed is less than the limit speed.

[0026] The controller can be configured to adjust the identified target speed based on a first compensation value when the temperature gradient of the drive motor in the current time period is less than the temperature gradient of the drive motor in the previous time period; and to adjust the identified target speed based on a second compensation value when the temperature gradient of the drive motor in the current time period is greater than or equal to the temperature gradient of the drive motor in the previous time period.

[0027] The controller can be configured to: adjust the identified target speed by adding the identified target speed and the first compensation value; and to adjust the identified target speed by subtracting the second compensation value from the identified target speed.

[0028] The oil pump can further include a filter configured to remove impurities from the oil delivered from the drive motor to the oil pump.

[0029] According to another aspect of the present invention, in a method of controlling a vehicle, the vehicle includes a drive motor configured to apply driving power to wheels and an oil pump configured to cool the drive motor. The method of controlling the vehicle includes: detecting the temperature of the oil; detecting the temperature of the drive motor; identifying a target speed of the oil pump corresponding to the detected temperature of the oil and the temperature of the drive motor; when the identified target speed is less than a limit speed, controlling the operation of the oil pump based on the identified target speed; and when the identified target speed is greater than or equal to the limit speed, adjusting the identified target speed based on the temperature gradient of the drive motor in the current time period and the temperature gradient of the drive motor in the previous time period, and controlling the operation of the oil pump based on the adjusted target speed.

[0030] Adjusting the identified target speed can include: when the temperature gradient of the drive motor in the current time period is less than the temperature gradient of the drive motor in the previous time period, adjusting the identified target speed by adding the first compensation value and the identified target speed; and when the temperature gradient of the drive motor in the current time period is greater than or equal to the temperature gradient of the drive motor in the previous time period, adjusting the identified target speed by subtracting the second compensation value from the identified target speed.

[0031] The method of controlling the vehicle can further include: detecting the current flowing through the drive motor; detecting the speed of the drive motor; obtaining the driving torque of the drive motor based on the detected current of the drive motor and the detected speed of the drive motor; when the obtained driving torque is greater than or equal to a reference torque, setting the limit speed based on a first ratio; and when the obtained driving torque is less than the reference torque, setting the limit speed based on a second ratio.

[0032] The limit speed can be a speed corresponding to a certain ratio of the maximum speed of a pump motor provided in the oil pump.

[0033] A method of controlling a vehicle may further include adjusting an identified target rotational speed based on a first compensation value when, in a state where a temperature gradient of a drive motor in a current time period is greater than or equal to a temperature gradient of the drive motor in a previous time period, the identified target rotational speed is less than a limit rotational speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] These aspects and / or other aspects of the present invention will become apparent and easier to understand from the following description of the embodiments and by reference to the accompanying drawings:

[0035] Figure 1 is a view showing a power unit of a vehicle according to an embodiment of the present invention.

[0036] Figure 2 is a view showing a connection structure between an oil pump and a drive motor provided in a vehicle according to an embodiment of the present invention.

[0037] Figure 3 is a control block diagram of a vehicle according to an embodiment of the present invention.

[0038] Figure 4 is a control flowchart of vehicle control according to an embodiment of the present invention.

[0039] Figure 5 is a control flowchart of a vehicle according to another embodiment of the present invention.

[0040] Figure 6A is a view showing a temperature detector provided on a front surface of a drive motor, Figure 6B is a view showing a temperature detector provided on a rear surface of a drive motor.

[0041] Figure 7A is a graph of temperatures detected by temperature detectors provided in Figure 6A and Figure 6B when oil is injected into the drive motor at a first injection amount.

[0042] Figure 7B is a graph of temperatures detected by temperature detectors provided in Figure 6A and Figure 6B when oil is injected into the drive motor at a second injection amount. DETAILED DESCRIPTION

[0043] It should be understood that the term "vehicle" or "vehicular" or other similar terms used herein generally include motor vehicles, such as passenger cars including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, vessels including various boats and ships, aircraft, etc., and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from non-petroleum energy sources). As mentioned herein, a hybrid vehicle is a vehicle having two or more power sources, such as a vehicle having both gasoline power and electric power.

[0044] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the present invention. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will also be understood that when the terms "comprises" and / or "comprising" are used in this specification, it specifies the presence of the stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Throughout the specification, unless explicitly stated to the contrary, the term "comprises" and variations such as "comprising" or "containing" should be understood to imply the inclusion of the stated element but not the exclusion of any other element. In addition, the terms "unit", "-device", "-part", and "module" described in the specification represent units for performing at least one function and operation, and can be implemented by hardware or software and combinations thereof.

[0045] In addition, the control logic of the present invention can be embodied as a permanent computer-readable medium on a computer-readable medium, including executable program instructions executed by a processor, controller, etc. Examples of computer-readable media include, but are not limited to, ROM, RAM, compact disc (CD)-ROM, magnetic tape, floppy disk, flash drive, smart card, and optical data storage devices. The computer-readable medium can also be distributed in network-connected computer systems so that the computer-readable medium is stored and executed in a distributed manner, such as through a telematics server or a controller area network (CAN).

[0046] It will also be understood that the term "connected" and its derivatives refer to both direct connection and indirect connection, and indirect connection includes connection through a wireless communication network.

[0047] It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from other regions, layers, or sections.

[0048] Reference numerals for method steps are for ease of explanation only and do not limit the order of the steps. Thus, unless the context clearly states otherwise, the written order may be otherwise.

[0049] Hereinafter, the operating principle and embodiments of the present invention will be described with reference to the accompanying drawings.

[0050] Figure 1 is an exemplary view showing a power unit of a vehicle according to an embodiment of the present invention, Figure 2 is an exemplary view showing a connection structure between an oil pump and a drive motor provided in a vehicle according to an embodiment of the present invention.

[0051] A vehicle according to an embodiment is a vehicle that receives electric power from a charger located in a parking lot or a charging station, charges a battery using the provided electric power, and drives a drive motor using the electric power charged in the battery to generate drive power, and may include an eco-friendly vehicle.

[0052] This embodiment describes an electric vehicle as an eco-friendly vehicle.

[0053] 》The vehicle 100 may include a body having external and internal components, and wheels 111 and a chassis 110, which are other components of the vehicle 1 in addition to the body, on which mechanical devices required for driving are mounted.

[0054] A charging port may be provided on the exterior of the body, through which a plug provided in an external charger is inserted and connected. Here, the charging port may include a charging terminal for slow charging and a charging terminal for fast charging.

[0055] The chassis 110 of the vehicle 100 is a frame for supporting the body, and wheels 111 are respectively installed at the front, rear, left, and right of the vehicle 100, a power system for applying drive power to the wheels 111, a steering system, a braking system for applying braking force to the wheels 111, and a suspension system.

[0056] The power system is a device that generates the drive power required to drive the vehicle 100 and regulates the generated drive power.

[0057] As Figure 1 shown, the power system may include a battery 112, a drive motor 113, and a power converter 114, and may further include a speed reducer 115.

[0058] The battery 112 can be charged by receiving power from an external power source through a plug inserted into a charging port in the charging mode, and can be charged by using the current caused by the back electromotive force generated by the drive motor 113 in the regenerative braking mode, and supply the charged power to the drive motor 113. Here, the external power source can be a charger provided in a parking lot or a charging station.

[0059] The vehicle 100 can include a first battery and a second battery. The first battery supplies drive power of a high-voltage current to a power system including the drive motor 113 and the oil pump 116; the second battery supplies drive power to electronic devices such as convenience devices and other devices. The convenience devices can include an audio device, an interior light, and audio / video / navigation (AVN).

[0060] The drive motor 113 can generate drive power for rotating the wheels 111 and transmit the generated drive power to the reduction gear 115.

[0061] The drive motor 113 can execute the regenerative braking mode under the conditions of energy regeneration by braking, decelerating, or low-speed driving, so as to operate as a generator through the rotational force (also referred to as rotational power) transmitted by the wheels 111, so that the battery 112 is charged.

[0062] When the operation mode of the vehicle 100 is in the charging mode, when power from an external power source is applied, the drive motor 113 can be used as a transformer and transformed, and then the transformed power is applied to the battery 112, so that the battery 112 is charged.

[0063] The drive motor 113 can include a circular stator and a rotor disposed on the outer periphery of the stator, and can further include a housing for accommodating the stator and the rotor.

[0064] The stator of the drive motor 113 can include: an annular base; a plurality of teeth disposed along the outer periphery of the base and protruding radially outward relative to the stator; and coils wound around each of the plurality of teeth. The coils can generate a magnetic field by the current flowing through the coils, and the plurality of teeth can be magnetized by the generated magnetic field.

[0065] The rotor of the drive motor 113 can include a plurality of permanent magnets disposed on the inner surface of the side wall, and these permanent magnets interact magnetically with the coils of the stator. This allows the rotor to rotate. The structure of the drive motor is only an example, and the structure of the drive motor is not limited thereto.

[0066] The power converter 114 can convert the power of the external power source into the charging power required to charge the battery 112, convert the power of the battery 112 into the drive power required to drive the drive motor 113, and convert the power of the battery 112 into the drive power required to drive the oil pump 116.

[0067] The power converter 114 can convert the power of the battery 112 into driving power for various devices in the vehicle 100.

[0068] The speed reducer 115 can change the revolutions per minute (RPM or rotational speed) of the drive motor 113 so that the traveling speed of the vehicle 100 reaches a target traveling speed. That is, the speed reducer 115 can generate driving power corresponding to the changed RPM of the drive motor 113 and transmit the generated driving power to the left wheel 111 and the right wheel 111, respectively.

[0069] The speed reducer 115 can change the input RPM of the drive motor 113 into a certain ratio.

[0070] The target traveling speed can be a speed corresponding to the depression of the accelerator pedal or the brake pedal, and can be a set traveling speed input by the user.

[0071] The oil pump 116 is preferably an electric oil pump and can include a pump motor 116a and a driver ( Figure 3 the second driver in

[0072] The oil pump 116 can pump oil and inject the oil into the drive motor 113 to adjust the temperature of the drive motor 113. The oil pump 116 can pump oil and supply the oil to the speed reducer 115 to maintain the hydraulic pressure and lubrication.

[0073] The oil pump 116 can operate continuously from when the vehicle 100 is started to when the vehicle 100 is shut down, and can also operate in the charging mode of the battery 113.

[0074] The vehicle 100 can further include: an oil reservoir that stores oil and is connected to the drive motor 113; a filter 116b that is provided between the oil reservoir and the oil pump 116 to remove impurities in the oil flowing from the oil reservoir to the oil pump 116; and a cooling water receiver 117 that receives cooling water and uses the supplied cooling water to lower the temperature of the oil.

[0075] The vehicle 100 can include: an oil passage 118 for transmitting the oil pumped by the oil pump 116 to the drive motor 113; and a heat exchanger 119 for lowering the temperature of the oil.

[0076] The oil pumped by the oil pump 116 can flow through the drive motor 113 via the oil passage 118. The oil pumped by the oil pump 116 can also flow through the speed reducer 115 via the oil passage 118.

[0077] As Figure 2As shown, the oil passage 118 may include: a first passage 118a for supplying oil; a second passage 118b connected to the first passage 118a and passing through the heat exchanger 119; a third passage 118c connected to the second passage 118b and injecting oil toward the drive motor 113; a fourth passage 118d for collecting the injected oil and transporting the collected oil to the filter 116b; and a fifth passage 118e connected to the fourth passage 118d and transporting the oil to the oil pump 116.

[0078] The cooling water receiver 117 may include a cooling water passage 117a that is disposed adjacent to the first passage 118a in the oil passage 118 and through which cooling water flows. The cooling water passage 117a may be connected to the heat exchanger 119. In addition, the cooling water passage 117a may be part of the heat exchanger 119.

[0079] In addition, the oil reservoir, the drive motor 113, and some of the third passage 118c may be accommodated together in a housing.

[0080] When the temperature of the oil is less than the reference temperature, the cooling water receiver 117 may block the flow of the cooling water through the heat exchanger 119 in response to a control command from the controller 130 (see Figure 3 ).

[0081] The heat exchanger 119 may use the cooling water flowing through the cooling water passage 117a of the cooling water receiver 117 to control the temperature of the oil flowing in the third passage 118c. At this time, the temperature of the oil flowing in the third passage 118c may be maintained at a constant temperature.

[0082] The vehicle 100 may include a first temperature detector 121 disposed in the third passage 118c to detect the temperature of the oil flowing in the third passage 118c, a second temperature detector 122 disposed in the drive motor 113 to detect the temperature of the drive motor 113, and may further include a third temperature detector 123 disposed in the fifth passage 118e to detect the temperature of the oil flowing in the fifth passage 118e.

[0083] Figure 3 is a control block diagram of a vehicle according to an embodiment of the present invention.

[0084] The vehicle 100 may include a battery 112, a drive motor 113, a power converter 114, an oil pump 116, a first temperature detector 121, a second temperature detector 122, a controller 130, a memory 131, a first driver 140, and a second driver 150.

[0085] The battery 112, the drive motor 113, the power converter 114, the oil pump 116, the first temperature detector 121, and the second temperature detector 122 have been described in Figure 1 and Figure 2 and the detailed description thereof will be omitted Figure 2 in

[0086] The vehicle 100 may further include: a speed detector for detecting the traveling speed; a first current detector for detecting the current flowing through the drive motor 113; a second current detector for detecting the current flowing through the pump motor 116a; a rotational speed detector for detecting the rotational speed of the drive motor 113; a first pressure detector for detecting the pressure applied to the accelerator pedal; and a second pressure detector for detecting the pressure applied to the brake pedal.

[0087] The controller 130 may obtain the required power of the user based on at least one of the current traveling speed of the vehicle 100, the pressure information applied to the accelerator pedal, and the pressure information applied to the brake pedal, obtain a target traveling speed corresponding to the obtained required power of the user, obtain a target rotational speed (i.e., the first target rotational speed) of the drive motor 113 corresponding to the obtained target traveling speed, and control the operation of the drive motor 113 based on the detected current of the drive motor 113 and the obtained first target rotational speed.

[0088] When controlling the operation of the drive motor 113, the controller 130 may electrically and mechanically connect the drive motor 113 and the first inverter, so as to apply the power converted by the first inverter to the coil provided in the drive motor 113.

[0089] In this way, the controller 130 may allow the vehicle 100 to be driven by the power generated from the drive motor 113.

[0090] Here, the time period during which the vehicle 100 travels may be the time period between the time point immediately after the start of startup and the time point immediately before the startup is turned off.

[0091] In addition, the controller 130 may control the cooling of the drive motor 113 while charging the battery 112 in the vehicle 100.

[0092] The controller 130 may identify the temperature of the oil detected by the first temperature detector 121 during traveling, and determine whether the identified temperature of the oil is lower than the reference temperature. When it is determined that the temperature of the oil is lower than the reference temperature, the controller 130 may stop and control the operation of the cooling water receiver 117. When it is determined that the identified temperature of the oil exceeds the reference temperature, the controller 130 may control the operation of the cooling water receiver 117. Thereby, the temperature of the oil delivered from the oil pump 116 to the drive motor 113 may be kept constant.

[0093] While the vehicle is in motion, the controller 130 may periodically obtain the temperature gradient of the drive motor 113 based on the temperature of the drive motor 113 detected by the second temperature detector 122, and periodically store the obtained temperature gradient. Here, the period may be about 0.5 ms.

[0094] While the vehicle is in motion, the controller 130 may compare the temperature gradient obtained in the current time period (i.e., the current temperature gradient) with the temperature gradient obtained in the previous time period (i.e., the previous temperature gradient). When the current temperature gradient is less than the previous temperature gradient, the controller 130 may control the operation of the pump motor 116a of the oil pump 116 based on the target rotational speed identified by referring to the mapping table. When the current temperature gradient is greater than or equal to the previous temperature gradient, the controller 130 may compare the identified target rotational speed with the limit rotational speed. When the target rotational speed identified in a state where the current temperature gradient is greater than or equal to the previous temperature gradient is less than the limit rotational speed, the controller 130 may adjust the target rotational speed based on the first compensation value. When the target rotational speed identified in a state where the current temperature gradient is greater than or equal to the previous temperature gradient is greater than or equal to the limit rotational speed, the controller 130 may adjust the target rotational speed based on the second compensation value.

[0095] While the vehicle is in motion, the controller 130 may identify the temperature of the drive motor 113 detected by the second temperature detector 122, and identify the target rotational speed (i.e., the second target rotational speed) of the pump motor 116a corresponding to the temperature of the identified drive motor 113 and the temperature of the oil identified by referring to the mapping table stored in the memory 131. The controller 130 may supply the oil pumped by the oil pump 116 to the drive motor 113 by controlling the rotational speed of the pump motor 116a based on the identified second target rotational speed. At this time, the temperature of the drive motor 113 may be maintained at a constant temperature by the oil. That is, overheating of the drive motor 113 may be prevented.

[0096] In addition, the oil pumped by the oil pump 116 may be supplied to the reduction gear 115.

[0097] The target rotational speed of the pump motor 116a in the mapping table stored in the memory 131 may increase in proportion to the temperature of the drive motor 113 and the identified temperature of the oil.

[0098] During driving, the controller 130 may compare a target rotational speed (i.e., a second target rotational speed) with a limit rotational speed of the pump motor 116a. When it is determined that the second target rotational speed is less than the limit rotational speed, the controller 130 may maintain the identified second target rotational speed. When it is determined that the second target rotational speed is greater than or equal to the limit rotational speed, the controller 130 may obtain a temperature gradient of the drive motor 113 in the current time period. The controller 130 may compare the temperature gradient of the drive motor 113 obtained in the current time period (which is referred to as the current temperature gradient) with the temperature gradient of the drive motor 113 obtained in the previous time period (which is referred to as the previous temperature gradient), and then adjust the second target rotational speed based on the comparison result.

[0099] The limit rotational speed may be a speed corresponding to a certain ratio of the maximum rotational speed of the pump motor 116a. Here, the certain ratio may be approximately 0.7. That is, the limit rotational speed (maximum RPM * 0.7) may be less than the maximum rotational speed (maximum RPM).

[0100] When it is determined that the current temperature gradient is less than the previous temperature gradient in a state where the second target rotational speed is greater than or equal to the limit rotational speed, the controller 130 may adjust the second target rotational speed based on a first compensation value. When it is determined that the current temperature gradient is greater than or equal to the previous temperature gradient in a state where the second target rotational speed is greater than or equal to the limit rotational speed, the controller 130 may adjust the second target rotational speed based on a second compensation value. The controller 130 may control the operation of the pump motor 116a of the oil pump 116 based on the maintained or adjusted second target rotational speed.

[0101] When adjusting the second target rotational speed based on the first compensation value, the controller 130 may obtain a new second target rotational speed by adding the first compensation value to the second target rotational speed, and adjust the identified second target rotational speed to the new second target rotational speed.

[0102] The first compensation value may be a constant value.

[0103] The first compensation value may be a value matching the temperature of the drive motor 113 or the temperature gradient of the drive motor 113, and the first compensation value may be provided by a first compensation mapping table. The first compensation value may be a value obtained through experiments.

[0104] At this time, the target rotational speed of the pump motor 116a of the oil pump 116 may be increased.

[0105] When adjusting the second target rotational speed based on the second compensation value, the controller 130 may obtain a new second target rotational speed by subtracting the second compensation value from the second target rotational speed, and adjust the rotational speed of the pump motor 116a to the new second target rotational speed. At this time, the target rotational speed of the pump motor 116a of the oil pump 116 may be decreased.

[0106] The second compensation value may be a constant value.

[0107] The second compensation value may be a value that matches the temperature of the drive motor 113 or the temperature gradient of the drive motor 113, and the second compensation value may be provided by a second compensation map. The second compensation value may be a value obtained through experiments.

[0108] The controller 130 may identify the current flowing through the pump motor 116a, obtain the actual rotational speed of the pump motor 116a based on the identified current, and control the operation of the pump motor 116a by comparing the obtained actual rotational speed with the second target rotational speed.

[0109] The controller 130 may also receive information about the actual rotational speed of the pump motor 116a from the second driver 150. In this case, the controller 130 may receive feedback on the actual rotational speed of the pump motor 116a during driving and control the driving of the pump motor 116a such that the actual rotational speed of the pump motor 116a is maintained at the determined second target rotational speed based on the actual rotational speed and the determined second target rotational speed.

[0110] The determined second target rotational speed may be any one of the maintained second target rotational speed, the second target rotational speed adjusted by the first compensation value, and the second target rotational speed adjusted by the second compensation value.

[0111] The controller 130 may directly diagnose a failure of the oil pump 116 and may receive failure information of the oil pump 116 from the second driver 150. At this time, the controller 130 may display the failure information of the oil pump 116 through a display provided on the vehicle 100, or store the failure information of the oil pump in the memory 131 and transmit the stored failure information of the oil pump 116 to a diagnostic program during a vehicle inspection.

[0112] When the temperature of the oil is greater than or equal to the reference temperature, the controller 130 may control the operation of the cooling water receiver 117 such that the temperature of the oil is reduced.

[0113] In addition, the cooling water receiver 117 may further include: a fan for performing heat exchange between the oil flowing in the oil passage 118 and the cooling water flowing in the cooling water passage 117a; and a valve for blocking the flow of the cooling water. When controlling the operation of the cooling water receiver 117, the controller 130 may control the valve to close to block the flow of the cooling water, control the valve to open to allow the cooling water to flow through the cooling water passage 117a, and control the fan so that heat exchange occurs between the cooling water and the oil.

[0114] The controller 130 according to an embodiment may be implemented using a memory and a processor. The memory stores algorithms for controlling the operation of components in the vehicle 100 or data related to programs for implementing the algorithms, and the processor uses the data stored in the memory to perform the above operations. The memory and the processor may be implemented in respective chips. Alternatively, the memory and the processor may be implemented in a single chip.

[0115] The controller 130 may be an electronic control unit (ECU) that controls the driving of the vehicle 100 and may be any one of a microcomputer, a CPU, and a processor.

[0116] The controller 130 according to an embodiment may include: a drive motor controller (MCU: Motor Control Unit), which controls the operation of the first inverter to rotate the drive motor 113 and performs regenerative braking during braking or deceleration; and a pump controller (PCU: Pump Control Unit), which controls the driving of the pump motor 116a provided in the oil pump 116.

[0117] The controller 130 provided in the vehicle 100 according to another embodiment may change the limit speed based on the driving torque of the drive motor 113, and control the second target speed of the pump motor 116a of the oil pump based on the comparison result between the changed limit speed and the second target speed, the temperature gradient of the drive motor 113 in the current time period, and the temperature gradient of the drive motor 113 in the previous time period.

[0118] That is, the controller 130 of the vehicle 100 according to another embodiment may obtain the driving torque of the drive motor 113 based on the rotational speed of the drive motor 113 (i.e., also referred to as RPM), compare the obtained driving torque with a reference torque, select a first ratio when the obtained driving torque is less than the reference torque, and select a second ratio when the obtained driving torque is greater than the reference torque. The controller 130 may obtain the limit speed based on the maximum speed and the selected constant ratio. When the obtained second target speed is less than the limit speed, the controller 130 may maintain the second target speed of the pump motor 116a as the second target speed obtained through a reference mapping table.

[0119] The controller 130 of the vehicle 100 according to another embodiment may obtain the driving torque based on the number of rotor magnetic poles of the drive motor 113, the magnetic flux of the permanent magnet, the inductance of the coil, the rotational speed of the rotor, and the q-axis current.

[0120] When the second target speed is greater than or equal to the limit speed, the controller 130 of the vehicle 100 according to another embodiment can adjust the second target speed of the pump motor 116a of the oil pump 116 based on the temperature gradient of the drive motor 113 in the current time period and the temperature gradient of the drive motor 113 in the previous time period. However, the controller 130 can adjust the second target speed of the pump motor 116a based on a first compensation value or a second compensation value.

[0121] The controller 130 according to another embodiment can be implemented using a memory and a processor. The memory stores algorithms for controlling the operation of components in the vehicle 100 or data related to programs for implementing the algorithms, and the processor uses the data stored in the memory to perform the above operations. The memory and the processor can be implemented in respective chips. Alternatively, the memory and the processor can be implemented in a single chip.

[0122] The memory 131 can store a reference mapping table that matches the target speed corresponding to the temperature of the oil and the temperature of the drive motor 113, and store the first compensation value and the second compensation value.

[0123] Here, the temperature of the drive motor 113 corresponding to the temperature of the oil and the target speed of the pump motor 116a of the oil pump 116 can be stored as a look-up table.

[0124] The memory 131 can also store a first compensation mapping table and a second compensation mapping table.

[0125] The memory 131 can also store information about a specific ratio related to obtaining the limit speed.

[0126] The memory 131 can periodically store the temperature gradient of the drive motor 113 in response to a control command from the controller 130.

[0127] The memory 131 can store a reference temperature for controlling the cooling of the oil.

[0128] The memory 131 can store information about the target speed of the pump motor 116a corresponding to the target flow rate.

[0129] The memory 131 can be a memory implemented using a chip separate from the above-mentioned processor related to the controller 130, or can be integrated with the processor in a single chip.

[0130] The memory 131 can be implemented by at least one of non-volatile storage devices such as cache memory, read-only memory (ROM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), volatile storage devices such as random access memory (RAM), or storage media such as a hard disk drive (HDD) or a compact disc (CD) ROM, but is not limited thereto.

[0131] The first driver 140 can drive the drive motor 113 in response to a control command from the controller 130. The first driver 140 can include a first inverter and can further include a rectifier.

[0132] The rectifier can include a full-bridge circuit and an LC filter, and the full-bridge circuit can include a plurality of switching elements.

[0133] The rectifier can use the full-bridge circuit to rectify high-voltage alternating current (AC) power and can use the LC filter to convert the AC power into a direct current (DC) voltage.

[0134] The first inverter can convert the DC voltage into a three-phase AC voltage in response to the charging voltage received from the battery 112 and apply the converted three-phase AC voltage to the drive motor 113. That is, when outputting the drive power of the drive motor 113, the first inverter can output the drive power of the drive motor 113 corresponding to the target rotational speed according to the control command of the controller 130. Here, the drive power of the drive motor 113 can be a switching signal for outputting a current corresponding to the target rotational speed and a switching signal for outputting a voltage corresponding to the target rotational speed.

[0135] The first inverter can include a plurality of switching elements and can further include diodes respectively connected to the plurality of switching elements.

[0136] The second driver 150 can drive the pump motor 116a of the oil pump 116 in response to a control command from the controller 130. The second driver 150 can include a second inverter and can further include a rectifier.

[0137] The rectifier can include a full-bridge circuit and an LC filter, and the full-bridge circuit can include a plurality of switching elements. The rectifier can use the full-bridge circuit to rectify high-voltage AC power and can use the LC filter to convert the AC power into a DC voltage. The second inverter can convert the DC voltage into a three-phase AC voltage in response to the charging voltage received from the battery 112 and apply the converted three-phase AC voltage to the pump motor 116a.

[0138] That is, when driving power of the output pump motor 116a is output, the second inverter can output driving power of the pump motor 116a corresponding to a target speed according to a control command of the controller 130. Here, the driving power of the pump motor 116a can be a switching signal for outputting a current corresponding to the target speed and a switching signal for outputting a voltage corresponding to the target speed.

[0139] The second inverter can include a plurality of switching elements and can further include diodes each connected to the plurality of switching elements.

[0140] The second driver 150 can function as the controller 130 for controlling the operation of the pump motor 116a of the oil pump 116.

[0141] That is, the second driver 150 can be connected by communicating with the controller 130 of the vehicle 100, and when receiving the temperature of the drive motor 113 from the controller 130 of the vehicle 100, the second driver can identify the detected oil temperature and the target speed of the oil pump 116 corresponding to the temperature of the drive motor 113. When the identified target speed is greater than the limit speed, the second driver can adjust the identified target speed based on the temperature gradient of the drive motor 113 in the current time period and the temperature gradient of the drive motor 113 in the previous time period, and control the operation of the oil pump 116 based on the adjusted target speed.

[0142] The second driver 150 can be provided in the oil pump 116 and can send and receive various types of information by performing communication with the controller 130.

[0143] The second driver 150 can diagnose a failure of the oil pump 116, diagnose a failure of the pump motor 116a, and send the diagnosis information to the controller 130.

[0144] The second driver 150 can obtain the actual speed of the pump motor 116a based on current information obtained by a current detector connected to the pump motor 116a, and send information related to the obtained actual speed of the pump motor 116a to the controller 130.

[0145] The second driver 150 can adjust the power applied to the pump motor 116a by performing pulse width modulation on at least one of the input current and voltage based on the speed of the pump motor 116a.

[0146] The oil pump 116 can receive driving power from the power converter 114.

[0147] When driving the pump motor 116a of the oil pump 116, the oil stored in the oil reservoir can flow to the drive motor 113 through the oil passage 118. At this time, the oil flowing into the drive motor 113 flows into the oil reservoir after being injected.

[0148] Figure 4 is a control flowchart of vehicle control according to an embodiment of the present invention.

[0149] The vehicle 100 can identify the temperature of the oil while driving (step 201).

[0150] Here, the temperature of the oil can be the temperature of the oil flowing in the third channel 118c detected by the first temperature detector 121, or the temperature of the oil flowing in the fifth channel 118e detected by the third temperature detector 123.

[0151] The temperature of the oil flowing in the third channel 118c can be the temperature of the oil passing through the heat exchanger 119. The temperature of the oil flowing in the fifth channel 118e can be the temperature of the oil passing through the filter.

[0152] The vehicle 100 can identify the temperature of the drive motor 113 detected by the second temperature detector 121 (step 202).

[0153] The vehicle 100 can identify the identified temperature of the oil and identify the target speed corresponding to the identified temperature of the drive motor 113 by using the reference mapping table stored in the memory 131 (step 203), thereby obtaining the temperature gradient of the drive motor 113 in the current time period and storing the obtained temperature gradient.

[0154] The vehicle 100 can periodically obtain the temperature gradient of the drive motor 113 based on the temperature of the drive motor 113 detected by the second temperature detector 122, and periodically store the obtained temperature gradient of the drive motor 113. The vehicle 100 can obtain and store the temperature gradient of the drive motor 113 at intervals of approximately 0.5 ms.

[0155] The vehicle 100 can compare the target speed with the limit speed of the pump motor 116a.

[0156] At this time, when the vehicle 100 determines that the target speed is less than the limit speed (step 204), the vehicle 100 can control the operation of the pump motor 116a so that the target speed of the pump motor 116a remains at the identified target speed (step 205). At this time, as at least one of the temperature of the drive motor 113 and the temperature of the oil increases, the identified target speed can increase.

[0157] The limit speed can be a speed corresponding to a certain ratio of the maximum speed of the pump motor 116a. The certain ratio can be approximately 0.7. That is, the limit speed (maximum RPM * 0.7) can be less than the maximum speed (maximum RPM).

[0158] When it is determined that the target speed of the pump motor 116a is greater than the limit speed, the vehicle 100 can obtain the temperature gradient of the pump motor 116a in the current time period and identify the temperature gradient of the pump motor 116a in the previous time period stored in the memory 131. The vehicle 100 can compare the obtained temperature gradient of the pump motor 116a in the current time period (which is referred to as the current temperature gradient) with the temperature gradient of the pump motor 116a in the previous time period (which is referred to as the previous temperature gradient).

[0159] When it is determined that the current temperature gradient is less than the previous temperature gradient (step 206), the vehicle 100 can adjust the identified target speed based on the first compensation value (step 207) and operate the pump motor 116a of the oil pump 116 based on the adjusted target speed. Here, the first compensation value can be a constant value. That is, the vehicle 100 can obtain a new target speed by adding the first compensation value and the identified target speed.

[0160] At this time, the injected oil volume can be greater than the oil volume corresponding to the identified target speed.

[0161] As described above, as the injected oil volume increases, the contact area of the drive motor 113 in contact with the oil increases, thereby improving the cooling efficiency of the drive motor 113.

[0162] In addition, when it is determined that the current temperature gradient is less than the previous temperature gradient, the vehicle 100 can identify the first compensation value through the first compensation mapping table, and can adjust the identified target speed by adding the first compensation value and the identified target speed, and operate the pump motor 116a of the oil pump 116 based on the adjusted target speed, so that the oil with a target flow rate corresponding to the adjusted target speed can be injected.

[0163] Here, the first compensation value can be a value corresponding to the temperature of the pump motor 116a or the temperature gradient of the pump motor 116a in the current time period, and can be a compensation speed.

[0164] On the other hand, when it is determined that the current temperature gradient is greater than or equal to the previous temperature gradient, the vehicle 100 can adjust the identified target speed based on the second compensation value (step 208) and operate the pump motor 116a of the oil pump 116 based on the adjusted target speed. Here, the second compensation value can be a constant value.

[0165] That is, the vehicle 100 can obtain a new second target speed by subtracting the second compensation value from the identified target speed, and operate the pump motor 116a so that the target speed of the pump motor 116a remains at the new target speed.

[0166] At this time, the new target rotational speed can be lower than the identified target rotational speed. Accordingly, the amount of oil injected from the oil pump 116 can be less than the amount corresponding to the identified target rotational speed.

[0167] That is, when the temperature gradient of the pump motor 116a increases, the target flow rate can be reduced by decreasing the target rotational speed of the pump motor 116a, thereby preventing oil from scattering from the drive motor 113. As a result, the cooling efficiency of the drive motor 113 can be improved.

[0168] In addition, when it is determined that the current temperature gradient is higher than the previous temperature gradient, the vehicle 100 can identify a second compensation value through a second compensation map, adjust the identified target rotational speed by subtracting the identified second compensation value from the identified target rotational speed, and operate the pump motor 116a of the oil pump 116 based on the adjusted target rotational speed, so that oil having a target flow rate corresponding to the adjusted target rotational speed can be injected.

[0169] Here, the second compensation value can be a value corresponding to the temperature of the pump motor 116a or the temperature gradient of the pump motor 116a in the current time period, and can be a compensation rotational speed.

[0170] Operating the pump motor 116a of the oil pump 116 can include performing pulse width modulation (PWM) of the current or voltage applied to the pump motor 116a.

[0171] In addition, the vehicle 100 can reduce the pumping temperature of the oil by using the cooling water receiver 117. This can include reducing the temperature of the oil by allowing cooling water to flow into the cooling water receiver 117 and performing heat exchange between the introduced cooling water and the oil.

[0172] In the present embodiment, after comparing the target rotational speed and the limit rotational speed, the current temperature gradient and the previous temperature gradient are compared, but the target flow rate can also be adjusted by comparing the current temperature gradient and the previous temperature gradient, and then the target rotational speed is compared with the limit rotational speed to adjust the target rotational speed of the pump motor 116a.

[0173] In addition, the vehicle 100 can compare the current temperature gradient and the previous temperature gradient, then compare the target rotational speed and the limit rotational speed, and compare the current temperature gradient and the previous temperature gradient again.

[0174] Figure 5 is a control flowchart of a vehicle according to another embodiment of the present invention.

[0175] The vehicle 100 can identify the temperature of the oil during traveling (step 211), and identify the temperature of the drive motor 113 detected by the second temperature detector 121 (step 212).

[0176] Here, the temperature of the oil can be the temperature of the oil flowing in the third channel 118c detected by the first temperature detector 121, or the temperature of the oil flowing in the fifth channel 118e detected by the third temperature detector 123.

[0177] The vehicle 100 can periodically obtain the temperature gradient of the drive motor 113 based on the temperature of the drive motor 113 detected by the second temperature detector 122, and periodically store the obtained temperature gradient of the drive motor 113. The vehicle 100 can obtain and store the temperature gradient of the drive motor 113 at intervals of approximately 0.5 ms.

[0178] The vehicle 100 can identify the identification temperature of the oil and identify the target speed corresponding to the identification temperature of the drive motor 113 (step 213) through the reference mapping table stored in the memory 131, so as to obtain the temperature gradient of the drive motor 113 in the current time period.

[0179] The vehicle 100 can obtain the drive torque of the drive motor 113 based on the target speed and current of the drive motor 113, and compare the obtained drive torque with the reference torque.

[0180] The vehicle 100 can obtain the drive torque of the drive motor 113 based on the actual speed and current of the drive motor 113.

[0181] When the obtained drive torque is less than the reference torque (step 214), the vehicle 100 can select the first ratio (step 215) and set the limit speed based on the selected first ratio. When the obtained drive torque is greater than the reference torque, the vehicle 100 can select the second ratio (step 216) and set the limit speed based on the selected second ratio. Here, the first ratio can be 1 and the second ratio can be 0.8.

[0182] That is, when the first ratio is selected, the limit speed can be the maximum speed * 1. When the second ratio is selected, the limit speed can be the maximum speed * 0.8.

[0183] When the drive torque of the drive motor 113 is less than the reference torque, it means that the temperature of the drive motor 113 is lower than the reference temperature.

[0184] The vehicle 100 can compare the target speed of the pump motor 116a with the limit speed.

[0185] At this time, when it is determined that the target speed is less than the set limit speed (step 217), the vehicle 100 can control the operation of the pump motor 116a so that the speed of the pump motor 116a remains at the determined target speed (step 218).

[0186] When it is determined that the target speed of the pump motor 116a is greater than the limit speed, the vehicle 100 can obtain the temperature gradient of the pump motor 116a in the current time period and identify the temperature gradient of the pump motor 116a in the previous time period stored in the memory 131. The vehicle 100 can compare the obtained temperature gradient of the pump motor 116a in the current time period (which is called the current temperature gradient) with the temperature gradient of the pump motor 116a in the previous time period (which is called the previous temperature gradient).

[0187] When it is determined that the current temperature gradient is less than the previous temperature gradient (step 219), the vehicle 100 can adjust the identified target speed based on the first compensation value (step 220) and operate the pump motor 116a of the vehicle's oil pump 116 based on the adjusted target speed.

[0188] Here, the first compensation value can be a constant value. That is, the vehicle 100 can obtain a new target speed by adding the first compensation value and the identified target speed. At this time, the injected oil volume can be greater than the oil volume corresponding to the identified target speed. As described above, as the injected oil volume increases, the contact area of the drive motor 113 in contact with the oil increases, thereby improving the cooling efficiency of the drive motor 113.

[0189] In addition, when it is determined that the current temperature gradient is less than the previous temperature gradient, the vehicle 100 can identify the first compensation value through the first compensation mapping table, and can adjust the identified target speed by adding the first compensation value and the identified target speed, and operate the pump motor 116a of the oil pump 116 based on the adjusted target speed, so that oil with a target flow rate corresponding to the adjusted target speed can be injected.

[0190] On the other hand, when it is determined that the current temperature gradient is greater than or equal to the previous temperature gradient, the vehicle 100 can adjust the identified target speed based on the second compensation value (step 221) and operate the pump motor 116a of the oil pump 116 based on the adjusted target speed. Here, the second compensation value can be a constant value.

[0191] That is, the vehicle 100 can obtain a new second target speed by subtracting the second compensation value from the identified target speed and operate the pump motor 116a so that the target speed of the pump motor 116a remains at the new target speed.

[0192] At this time, the new target speed can be lower than the identified target speed. Therefore, the oil volume injected from the oil pump 116 can be less than the oil volume corresponding to the identified target speed.

[0193] Additionally, when it is determined that the current temperature gradient is higher than the previous temperature gradient, the vehicle 100 can identify a second compensation value through a second compensation mapping table, adjust the identified target rotational speed by subtracting the identified second compensation value from the identified target rotational speed, and operate the pump motor 116a of the oil pump 116 based on the adjusted target rotational speed, so that oil with a target flow rate corresponding to the adjusted target rotational speed can be injected.

[0194] Here, the second compensation value can be a value corresponding to the temperature of the pump motor 116a or the temperature gradient of the pump motor 116a in the current time period, and can be a compensation rotational speed.

[0195] In another embodiment, the current temperature gradient and the previous temperature gradient are compared after comparing the target rotational speed and the limit rotational speed, but in another embodiment, the target rotational speed and the limit rotational speed are compared after comparing the current temperature gradient and the previous temperature gradient. In contrast, the target flow rate can also be controlled by adjusting the target rotational speed of the pump motor 116a.

[0196] In another embodiment, the vehicle 100 can compare the temperature gradient in the current time period with the temperature gradient in the previous time period. As a result of the comparison, when the temperature gradient in the current time period is less than the temperature gradient in the previous time period (i.e., when it is determined that the temperature gradient of the drive motor is not large), the vehicle 100 can maintain the rotational speed of the oil pump 116 at the target rotational speed. When the temperature gradient in the current time period is greater than the temperature gradient in the previous time period (i.e., if it is determined that the temperature change of the drive motor is large), the vehicle 100 can identify the target rotational speed corresponding to the temperature of the oil and the drive motor 113, and compare the identified target rotational speed with the limit rotational speed. As a result of the comparison, when the identified target rotational speed is less than the limit rotational speed, the vehicle 100 can adjust the target rotational speed based on the first compensation value. When the target rotational speed is higher than the limit rotational speed, the vehicle 100 can adjust the target rotational speed based on the second compensation value.

[0197] Here, adjusting the target rotational speed based on the first compensation value can include increasing the target rotational speed.

[0198] Adjusting the target rotational speed based on the second compensation value can include reducing the target rotational speed.

[0199] Figure 6A is a view showing the temperature detector provided on the front surface of the drive motor, Figure 6B is a view showing the temperature detector provided on the rear surface of the drive motor.

[0200] Figure 7A and Figure 7B is when oil corresponding to the first injection amount (8 LPM (liters per minute)) and the second injection amount (9 LPM) is injected into the drive motor 113, byFigure 6A and Figure 6B The curve graph of the temperature detected by the temperature detector set in

[0201] When the vehicle 100 is in a state of traveling at the maximum constant speed (200 kph), the target rotational speed of the drive motor 113 can be 15,800 rpm and the drive torque can be 67 Nm.

[0202] By increasing the effective cooling oil effectively used for actual cooling, LPM can be saved, and the oil cooling performance can be improved.

[0203] The result of the test is that although the oil injection amount increases from 8 LPM to 9 LPM, the test available time decreases from 320 [seconds] (8 LPM) to 225 [seconds] (9 LPM), and the 9 LPM case shows poor cooling performance.

[0204] In particular, the temperatures at positions ②, ⑧, ⑤, and ⑦ show that the temperature rises rapidly at 9 LPM compared to 8 LPM. This is very effective for the cooling used for actual cooling because the oil does not contact or impact the coil but scatters as the injection amount increases. This is because the amount of effective oil decreases.

[0205] Therefore, in the present invention, increasing the injection amount but having poor cooling performance is determined to be due to the reduction in the amount of effective cooling oil. Thus, the present invention reduces the oil injection amount (for example, 9 LPM → 8 LPM) and improves the cooling performance.

[0206] The present invention can reduce the load on the oil pump 116 by preventing the oil pump 116 from rotating unnecessarily at the maximum rotational speed, thereby reducing the total load and improving power consumption.

[0207] According to the present invention, the driving distance can be increased in response to the improvement of fuel consumption.

[0208] It is obvious from the above description that the present invention can increase the oil injection speed in response to the increase in the temperature of the drive motor, but can effectively cool the drive motor by adjusting the oil injection speed based on the temperature gradient of the drive motor.

[0209] The present invention can prevent damage to the drive motor through effective cooling of the drive motor, extend the life of the drive motor, and prevent demagnetization of the permanent magnet of the drive motor, thereby improving the performance of the drive motor.

[0210] The present invention can prevent over - driving of the oil pump for cooling the drive motor, thereby preventing the failure of the oil pump and extending the life of the oil pump. Therefore, vehicle failures can be prevented, vehicle stability can be improved, and vehicle fuel consumption can be improved.

[0211] The present invention can reduce the total load by suppressing inefficient overload in the oil pump, thereby increasing the driving distance of the vehicle.

[0212] As described above, the present invention can improve the quality and marketability of the oil pump and the eco-friendly vehicle, and further improve user satisfaction, user convenience and vehicle safety, and ensure product competitiveness.

[0213] The disclosed embodiments can be implemented in the form of a recording medium storing computer-executable instructions executable by a processor. The instructions can be stored in the form of program code, and when executed by the processor, the instructions can generate program modules to perform the operations of the disclosed embodiments. The recording medium can be implemented as a non-transitory computer-readable recording medium.

[0214] The non-transitory computer-readable recording medium can include all kinds of recording media storing commands interpretable by a computer. For example, the non-transitory computer-readable recording medium can be, for example, ROM, RAM, magnetic tape, magnetic disk, flash memory, optical data storage device, etc.

[0215] So far, embodiments of the present invention have been described with reference to the accompanying drawings. It will be apparent to those of ordinary skill in the art that the present invention can be practiced in other forms than the above-described embodiments without changing the technical concept or basic features of the present invention. The above embodiments are merely exemplary and should not be construed in a limiting sense.

Claims

1. A vehicle, comprising: A drive motor connected to a wheel, the drive motor being configured to apply drive power to the wheel; An oil pump configured to cool the drive motor by supplying oil to the drive motor; A first temperature detector configured to detect the temperature of the oil; A second temperature detector configured to detect the temperature of the drive motor; And A controller configured to: Identify a target speed of the oil pump corresponding to the detected temperature of the oil and the temperature of the drive motor; When the identified target speed is greater than or equal to a limit speed, adjust the identified target speed based on the temperature gradient of the drive motor in the current time period and the temperature gradient of the drive motor in the previous time period; Control the operation of the oil pump based on the adjusted target speed.

2. The vehicle according to claim 1, further comprising: A memory configured to store information related to a target speed that matches in response to the detected temperature of the oil and the temperature of the drive motor as a reference mapping table, Wherein, the controller is configured to identify the target speed through the reference mapping table when the identified target speed is less than the limit speed.

3. The vehicle according to claim 1, wherein, When the temperature gradient of the drive motor in the current time period is less than the temperature gradient of the drive motor in the previous time period, the controller is configured to adjust the identified target speed based on a first compensation value.

4. The vehicle according to claim 3, wherein, The controller is configured to adjust the identified target speed by adding the identified target speed and the first compensation value.

5. The vehicle according to claim 1, wherein, When the temperature gradient of the drive motor in the current time period is greater than or equal to the temperature gradient of the drive motor in the previous time period, the controller is configured to adjust the identified target speed based on a second compensation value.

6. The vehicle according to claim 5, wherein, The controller is configured to adjust the identified target speed by subtracting the second compensation value from the identified target speed.

7. The vehicle according to claim 1, further comprising: A power converter connected to a battery, the power converter being configured to convert the power charged in the battery into power for driving the drive motor and the oil pump.

8. The vehicle according to claim 1, further comprising: A cooling water receiver configured to supply cooling water; And A heat exchanger disposed adjacent to an oil passage connected to the oil pump and disposed in a cooling water passage of the cooling water receiver, the heat exchanger being configured to perform heat exchange between the oil and the cooling water.

9. The vehicle according to claim 1, further comprising: A filter is provided between the drive motor and the oil pump, the filter being configured to remove impurities from the oil delivered to the oil pump.

10. The vehicle according to claim 1, further comprising: A current detector and a speed detector, the current detector being configured to detect the current flowing through the drive motor; The speed detector is configured to detect the speed of the drive motor, Wherein, the controller is configured to: Obtain the drive torque of the drive motor based on the detected current of the drive motor and the detected speed of the drive motor; When the obtained drive torque is greater than or equal to a reference torque, set the limit speed based on a first ratio; When the obtained driving torque is less than the reference torque, the limiting rotational speed is set based on a second ratio.

11. An oil pump, comprising: a driver connected by communicating with a controller provided in a vehicle, the driver configured to receive power for driving from a power converter provided in the vehicle; a pump motor configured to operate by a control command of the driver; and a temperature detector configured to detect the temperature of oil, wherein the driver is configured to: when receiving the temperature of the drive motor, identify the target rotational speed of the oil pump corresponding to the detected temperature of the oil and the received temperature of the drive motor; when the identified target rotational speed is greater than or equal to the limiting rotational speed, adjust the identified target rotational speed based on the temperature gradient of the drive motor in the current time period and the temperature gradient of the drive motor in the previous time period; control the operation of the pump motor based on the adjusted target rotational speed.

12. The oil pump according to claim 11, further comprising: a memory configured to store, as a reference mapping table, information related to the target rotational speed that matches in response to the detected temperature of the oil and the temperature of the drive motor, wherein the controller is configured to identify the target rotational speed through the reference mapping table when the identified target rotational speed is less than the limiting rotational speed.

13. The oil pump according to claim 11, wherein, The controller is configured to: when the temperature gradient of the drive motor in the current time period is less than the temperature gradient of the drive motor in the previous time period, adjust the identified target rotational speed based on a first compensation value; and when the temperature gradient of the drive motor in the current time period is greater than or equal to the temperature gradient of the drive motor in the previous time period, adjust the identified target rotational speed based on a second compensation value.

14. The oil pump according to claim 13, wherein, The controller is configured to: adjust the identified target rotational speed by adding the identified target rotational speed and the first compensation value; adjust the identified target rotational speed by subtracting the second compensation value from the identified target rotational speed.

15. The oil pump according to claim 11, further comprising: a filter configured to remove impurities from the oil delivered from the drive motor to the oil pump.

16. A method of controlling a vehicle, the vehicle including a drive motor configured to apply driving power to wheels and an oil pump configured to cool the drive motor, the method of controlling the vehicle includes: detecting the temperature of the oil by a first temperature detector; detecting the temperature of the drive motor by a second temperature detector; identifying, by a controller, the target rotational speed of the oil pump corresponding to the detected temperature of the oil and the temperature of the drive motor; when the identified target rotational speed is less than the limiting rotational speed, controlling the operation of the oil pump by the controller based on the identified target rotational speed; and when the identified target rotational speed is greater than or equal to the limiting rotational speed, adjusting, by the controller, the identified target rotational speed based on the temperature gradient of the drive motor in the current time period and the temperature gradient of the drive motor in the previous time period, and controlling the operation of the oil pump based on the adjusted target rotational speed.

17. The method of controlling a vehicle according to claim 16, wherein, Adjusting the identified target rotational speed includes: When the temperature gradient of the drive motor in the current time period is less than the temperature gradient of the drive motor in the previous time period, the identified target speed is adjusted by adding the first compensation value and the identified target speed; When the temperature gradient of the drive motor in the current time period is greater than or equal to the temperature gradient of the drive motor in the previous time period, the identified target speed is adjusted by subtracting the second compensation value from the identified target speed.

18. The method for controlling a vehicle according to claim 16, further comprising: Detecting the current flowing through the drive motor; Detecting the speed of the drive motor; Obtaining the drive torque of the drive motor based on the detected current of the drive motor and the detected speed of the drive motor; When the obtained drive torque is greater than or equal to the reference torque, setting a limit speed based on a first ratio; And When the obtained drive torque is less than the reference torque, setting a limit speed based on a second ratio.

19. The method of controlling a vehicle according to claim 16, wherein, The limit speed is a speed corresponding to a certain ratio of the maximum speed of the pump motor provided in the oil pump.

20. The method for controlling a vehicle according to claim 16, further comprising: When, in a state where the temperature gradient of the drive motor in the current time period is greater than or equal to the temperature gradient of the drive motor in the previous time period, the identified target speed is less than the limit speed, adjusting the identified target speed based on the first compensation value.

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