Electric vehicle wireless charging device
The wireless charging device uses a distributed temperature sensor with optical fibers to detect and locate foreign objects, addressing limitations of conventional methods and enhancing safety and efficiency by preventing fire accidents and improving charging performance.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- LS CABLE & SYST LTD
- Filing Date
- 2025-05-12
- Publication Date
- 2026-06-25
AI Technical Summary
Conventional methods for detecting foreign objects during electric vehicle wireless charging are limited in sensing the entire area, fail to detect non-conductive objects like living creatures, and cannot accurately identify their location, leading to reduced charging efficiency and fire risks.
A wireless charging device equipped with a distributed temperature sensor using optical fibers arranged in specific patterns to detect temperature changes and locate foreign objects, particularly living creatures, by analyzing scattered light patterns and elapsed time of laser pulses.
Effectively detects and locates foreign objects, improving charging efficiency and preventing fire accidents by accurately identifying the presence and movement of creatures like cats and dogs, enhancing safety and efficiency.
Smart Images
Figure KR2025006403_25062026_PF_FP_ABST
Abstract
Description
Electric vehicle wireless charging device
[0001] The present invention relates to a wireless charging device for electric vehicles. Specifically, the present invention relates to a wireless charging device for electric vehicles that can improve charging efficiency and prevent fire accidents by effectively and continuously detecting the presence and location of foreign objects, particularly living creatures such as cats and dogs, that interfere with charging between an electric vehicle parked for charging and the charging device.
[0002] Internal combustion engine vehicles are being replaced with electric vehicles as a means to reduce greenhouse gas emissions, and demand is rapidly increasing as the number of people who prefer electric vehicles grows due to technological advancements.
[0003] However, compared to the increasing adoption rate of electric vehicles, charging areas and facilities are still insufficient, and the turnover rate of charging areas is particularly low. This is because electric vehicle charging areas require more space than internal combustion engine gas stations, and charging times are considerably longer.
[0004] Therefore, wireless charging technology for electric vehicles is being researched and developed to improve turnover, such as by minimizing the space required for charging areas and shortening charging times.
[0005] FIG. 1 schematically illustrates one embodiment of an electric vehicle wireless charging device.
[0006] As illustrated in FIG. 1, when an electric vehicle (EV) is parked or stopped in a wireless charging area, AC power is supplied from a power supply unit (100) located near the charging area to a transmitting coil of a charging unit (200) located on the floor of the charging area, and current is flowed to the receiving coil through electromagnetic induction between the transmitting coil and the receiving coil located at the bottom of the electric vehicle, and the current is rectified through a rectifier inside the electric vehicle and then charged to the connected battery.
[0007] That is, electric vehicle wireless charging is a method that utilizes electromagnetic induction between a receiving coil provided at the bottom of the electric vehicle and a transmitting coil provided at the top of the charging unit (200) of the charging device, with the receiving coil and the transmitting coil separated by a certain distance from each other. However, if there is a conductive foreign object or foreign substance such as metal on the charging unit (200), the temperature may rise locally due to eddy currents, which may cause a fire. Also, if there is a non-conductive foreign object, particularly a living creature such as a cat or dog, there may be interference with electromagnetic induction, which may reduce charging efficiency.
[0008] Conventional technologies for detecting foreign objects or substances in electric vehicle wireless charging devices include a power analysis method that detects abnormal power consumption caused by foreign objects or substances by monitoring power consumed during the charging process, a temperature analysis method that detects temperature changes caused by metal foreign objects or substances, a frequency analysis method that detects frequency changes caused by metal foreign objects or substances, a ripple current analysis method that detects ripple current caused by metal foreign objects or substances, and a vision camera analysis method that detects foreign objects or substances using a vision camera.
[0009] However, conventional methods for analyzing power, temperature, frequency, and ripple current caused by foreign objects or substances have limitations. It is difficult to sense the entire area where the transmitting coil is placed, and it is also difficult to detect non-conductive foreign objects, substances, or living organisms such as cats and dogs. Furthermore, it is impossible to identify the location of such foreign objects, and they may even cause noise that interferes with wireless charging. While using a vision camera makes it possible to detect living organisms and their locations, there is the issue of having to install a separate vision camera.
[0010] Therefore, there is an urgent need for a wireless electric vehicle charging device that can improve charging efficiency and prevent fire accidents by effectively and continuously detecting the presence and location of foreign objects, particularly living creatures such as cats and dogs, that interfere with charging between an electric vehicle parked for charging and the charging device.
[0011] The present invention aims to provide a wireless electric vehicle charging device capable of improving charging efficiency and preventing fire accidents by effectively and continuously detecting the presence and location of foreign objects, particularly living creatures such as cats and dogs, that interfere with charging between an electric vehicle parked for charging and the charging device.
[0012] To solve the above problem, the present invention,
[0013] The present invention provides a wireless charging device for an electric vehicle, comprising: a power supply unit that supplies power from an external source for charging an electric vehicle; and a charging unit that charges a battery of an electric vehicle using power supplied from the power supply unit, wherein the charging unit includes a transmitting coil that generates current in a receiving coil equipped in an electric vehicle using electromagnetic induction and an insulator that surrounds the transmitting coil, and a transmitting unit buried in a road and a temperature sensor disposed between the receiving coil of the electric vehicle and the transmitting unit to detect the temperature of the transmitting unit at each location, wherein the temperature sensor includes a distributed temperature sensor in which an optical fiber is arranged in a certain pattern on a base substrate and a laser pulse is applied to one end of the optical fiber and the scattered light returning is analyzed.
[0014] Herein, the electric vehicle wireless charging device is provided, characterized in that the optical fiber comprises one or more zones wound at least once on the base substrate, selected from a group consisting of circular, elliptical, and rectangular shapes, and is arranged to be connected overall.
[0015] In addition, the electric vehicle wireless charging device is provided, characterized in that the optical fiber is arranged to be bent in a zigzag pattern on the base substrate and connected as a whole.
[0016] Furthermore, the present invention provides an electric vehicle wireless charging device characterized by including a pair of optical fibers that are each bent in a zigzag pattern to intersect each other on the base substrate and are connected as a whole.
[0017] Meanwhile, the electric vehicle wireless charging device is provided, characterized in that the optical fiber is positioned to cover an area where the transmitting coil of the transmitting unit is positioned and an internal empty space area of the positioned transmitting coil.
[0018] In addition, the present invention provides a wireless charging device for electric vehicles characterized in that the scattered light comprises one or more types of scattered light selected from the group consisting of Rayleigh, Raman, and Brillouin.
[0019] Herein, the electric vehicle wireless charging device is characterized by the temperature sensor measuring the temperature using a relationship between the intensity of the scattered light and the temperature, measuring the elapsed time of the returning scattered light to measure the length of the point where a temperature change occurs from one end of the optical fiber where a laser pulse is injected, and applying the length to the optical fiber pattern to determine the location where the temperature change is detected.
[0020] In addition, the electric vehicle wireless charging device is provided, characterized in that the laser pulse is injected through a laser diode (LD) or a photodiode (PD) at one end of the optical fiber.
[0021] In addition, the above-mentioned transmitting coil may be made of copper, aluminum, or an alloy thereof, and the above-mentioned insulator may be made of ethylene propylene rubber or a polyolefin-based resin, thereby providing an electric vehicle wireless charging device.
[0022] Meanwhile, an electric vehicle equipped with a receiving coil; and an electric vehicle wireless charging system comprising the electric vehicle wireless charging device are provided.
[0023] The electric vehicle wireless charging device according to the present invention is equipped with a temperature sensor using optical fibers, thereby effectively and continuously detecting the presence and location of foreign objects, particularly living creatures such as cats and dogs, that interfere with charging between the electric vehicle parked for charging and the charging device, thereby improving charging efficiency and preventing fire accidents, and exhibiting excellent effects.
[0024] FIG. 1 schematically illustrates one embodiment of an electric vehicle wireless charging device.
[0025] FIG. 2 schematically illustrates one embodiment of the charging part of the electric vehicle wireless charging device illustrated in FIG. 1.
[0026] FIG. 3 schematically illustrates embodiments of a temperature sensor in a charging unit shown in FIG. 2.
[0027] Figure 4 schematically illustrates the operating principle of the temperature sensor shown in Figure 3.
[0028] Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete, and to ensure that the spirit of the present invention is sufficiently conveyed to those skilled in the art. Throughout the specification, the same reference numerals indicate the same components.
[0029] The present invention relates to an electric vehicle wireless charging device, and also to an electric vehicle wireless charging system including an electric vehicle wireless charging device and an electric vehicle.
[0030] As illustrated in FIG. 1, the electric vehicle wireless charging device according to the present invention may include a power supply unit (100) that supplies power from an external source for charging an electric vehicle (EV) and a charging unit (200) that charges the battery of the electric vehicle (EV) using the power supplied from the power supply unit (100).
[0031] FIG. 2 schematically illustrates one embodiment of the charging part of the electric vehicle wireless charging device illustrated in FIG. 1.
[0032] As illustrated in FIG. 2, the charging unit (200) may include a transmitting coil (211) that generates current in a receiving coil provided at the bottom of an electric vehicle (EV) using electromagnetic induction, an insulator (212) that surrounds the transmitting coil, a transmitting unit (210) embedded in a road, a temperature sensor (220) disposed between the receiving coil of the electric vehicle and the transmitting unit (210) to detect the temperature at each location of the transmitting unit (210), etc.
[0033] Specifically, the transmitting coil (211) may be made of a cylindrical conductor made of a conductive metal such as copper, aluminum, or an alloy thereof, and a channel for a cooling fluid to cool the conductor may be formed inside or outside the conductor, and the conductor may be rapidly cooled through heat exchange with a cooling fluid circulating along the cooling fluid channel when heat is generated by the flow of current.
[0034] Here, if the flow path of the cooling fluid is formed inside the conductor, it may be provided as a hollow part, and if the flow path of the cooling fluid is formed outside the conductor, it may be provided as a separate cooling fluid tube.
[0035] In addition, the cooling fluid may be provided in a liquid form capable of cooling and flow with a thermal conductivity of about 0.1 to 0.5 W / mK, and may be a cooling liquid in which at least one additive is added among inorganic additives such as ethylene glycol, phosphate, silicate, borate, antifreeze, corrosion inhibitor, high temperature stability enhancer, anti-foaming agent, or alkaline additive, in addition to pure water or insulating oil.
[0036] Meanwhile, even if the cooling fluid leaks to the outside due to the occurrence of a hole or crack in the conductor, it is preferable that the cooling fluid be insulating oil or insulating oil with the additive added to ensure electrical insulation.
[0037] The insulator (212) may be a liquid insulating material contained in a case on which the transmitting coil (211) can be mounted, or it may be in the form of an insulating layer that surrounds the conductor of the transmitting coil (211), and it may be made of a plastic material such as rubber such as ethylene propylene rubber (EPR) or a polyolefin resin.
[0038] The insulator (212) may have a thermal conductivity of about 0.15 to 0.6 W / mK to assist in cooling the conductor by releasing heat transferred from the conductor to the outside when the conductor constituting the transmitting coil (211) heats up.
[0039] FIG. 3 schematically illustrates embodiments of a temperature sensor in a charging unit shown in FIG. 2.
[0040] The above temperature sensor (220) may be a distributed temperature sensor capable of analyzing scattered light returning after a laser pulse is applied to one end of the optical fiber, wherein the optical fiber (221) is arranged in a certain pattern on a base substrate (222). Specifically, the optical fiber (221) may be arranged to include one or more sections wound at least once in a circular, elliptical, or rectangular shape as shown in FIG. 3a and connected as a whole, may be arranged to be bent in a zigzag shape and connected as a whole as shown in FIG. 3b, and may be arranged to be bent in a zigzag shape so that a pair of optical fibers (221a, 221b) connected as a whole each intersect each other as shown in FIG. 3c.
[0041] Here, the optical fiber (221) may be positioned to cover both the area where the transmitting coil of the transmitting unit (220) is positioned and the internal empty space area of the positioned transmitting coil.
[0042] The temperature sensor (220) using the optical fiber (221) may be a distributed temperature sensor (DTS) using scattered light. When light passes through a transparent dielectric material, some of the light is scattered due to dielectric non-homogeneity. When light passes through the optical fiber (221), which is a dielectric material, various types of scattering naturally occur, such as Rayleigh, Raman, and Brillouin scattering.
[0043] Such light scattering is a harmful aspect that causes light transmission loss in optical communication, but since light is scattered throughout the entire optical fiber due to the material properties of the optical fiber, this information can be utilized to make the entire optical fiber a beneficial part that can be used as a light sensor.
[0044] In particular, the distributed temperature sensor (DTS) injects a laser pulse into the optical fiber (221) and measures the intensity and time of the scattered light returning to calculate the temperature distribution and distance. The temperature measurement is performed using the relationship between the intensity of the scattered light and the temperature, and the distance measurement can be performed using the principle of the Optical Time Domain Reflectometer (OTDR), that is, by measuring the elapsed time of the returning light and converting it into distance.
[0045] Figure 4 schematically illustrates the operating principle of the temperature sensor shown in Figure 3.
[0046] As shown in FIG. 4, for example, a laser pulse can be injected into one end of the optical fiber (221) equipped in the temperature sensor (220) using a laser diode (LD) or a photodiode (PD), and the intensity and time of the returning Raman backscattered light can be measured to determine the temperature distribution by location.
[0047] Here, since the optical fiber (221) has a constant length and is connected as a whole, the length from one end where a laser pulse is injected to the place where a temperature change is detected is measured and then applied to the pattern in which the optical fiber (221) is arranged to determine the location where the temperature change is detected.
[0048] For example, the total length of the entire connected optical fiber (221) is 100 m, and as shown in FIG. 3a, there are a total of 10 areas that are wound one or more times sequentially from 1 to 10. Based on one end of the optical fiber (221) into which a laser pulse is injected, the areas can be distributed in a pattern such as area 1 being 0 to 8 m, area 2 being 10 to 18 m, area 3 being 20 to 28 m, area 4 being 30 to 38 m, and area 5 being 40 to 48 m. If scattered light caused by a foreign object is detected when the length calculated from the time the scattered light returns after the laser pulse is introduced into one end of the optical fiber (221) is 42 m, the location of the foreign object can be estimated to be area 5, which includes a length of 42 m.
[0049] Thus, by effectively detecting the presence and location of foreign objects that interfere with charging between an electric vehicle parked for charging and a charging device, it is possible to improve charging efficiency and prevent fire accidents caused by heat generated by foreign objects. Furthermore, since living creatures such as cats and dogs are highly likely to change their location, if the location of the foreign object can be detected, a change in the foreign object's position can be detected, and from this, it can be inferred that the foreign object is a living creature, allowing for the selective taking of appropriate measures depending on the type of foreign object.
[0050] Although this specification has been described with reference to preferred embodiments of the present invention, those skilled in the art may make various modifications and changes to the present invention without departing from the spirit and scope of the present invention as described in the claims below. Therefore, if a modified embodiment basically includes the components of the claims of the present invention, it should be considered to be included within the technical scope of the present invention.
Claims
1. As an electric vehicle wireless charging device, A power supply unit that supplies power from an external source for charging an electric vehicle; and It includes a charging unit that charges the battery of an electric vehicle using power supplied from the above power supply unit, and The charging unit comprises a transmitting coil that generates current in a receiving coil equipped in an electric vehicle using electromagnetic induction, an insulator surrounding the transmitting coil, a transmitting unit embedded in a road, and a temperature sensor positioned between the receiving coil of the electric vehicle and the transmitting unit to detect the temperature at each location of the transmitting unit. The above temperature sensor is a wireless charging device for an electric vehicle, comprising a distributed temperature sensor capable of analyzing scattered light returning after applying a laser pulse to one end of the optical fiber, wherein the optical fiber is arranged in a specific pattern on a base substrate.
2. In Paragraph 1, An electric vehicle wireless charging device characterized in that the optical fiber comprises one or more zones wound at least once on the base substrate, selected from a group consisting of circular, elliptical, and rectangular shapes, and is arranged to be connected as a whole.
3. In Paragraph 1, An electric vehicle wireless charging device characterized in that the optical fiber is arranged to be bent in a zigzag pattern on the base substrate and connected as a whole.
4. In Paragraph 1, An electric vehicle wireless charging device characterized by including a pair of optical fibers that are each bent in a zigzag pattern to intersect each other on the base substrate and are connected as a whole.
5. In any one of paragraphs 1 through 4, An electric vehicle wireless charging device characterized in that the optical fiber is positioned to cover an area where the transmitting coil of the transmitting unit is positioned and an internal empty space area of the positioned transmitting coil.
6. In any one of paragraphs 1 through 4, An electric vehicle wireless charging device characterized in that the scattered light comprises one or more types of scattered light selected from the group consisting of Rayleigh, Raman, and Brillouin.
7. In Paragraph 6, An electric vehicle wireless charging device characterized by the above temperature sensor measuring the temperature using a relationship between the intensity of the scattered light and the temperature, measuring the elapsed time of the returning scattered light to measure the length of the point where a temperature change occurs from one end of the optical fiber where a laser pulse is injected, and applying the length to the optical fiber pattern to determine the location where the temperature change is detected.
8. In any one of paragraphs 1 through 4, An electric vehicle wireless charging device characterized in that the laser pulse is injected through a laser diode (LD) or a photodiode (PD) at one end of the optical fiber.
9. In any one of paragraphs 1 through 4, The above-mentioned transmitting coil may be made of copper, aluminum, or an alloy thereof, and An electric vehicle wireless charging device characterized in that the insulator is made of ethylene propylene rubber or a polyolefin-based resin.
10. An electric vehicle equipped with a receiving coil; and An electric vehicle wireless charging system comprising an electric vehicle wireless charging device according to any one of paragraphs 1 to 4.