Electric bicycle wireless charging coil calibration system and method

Abstract

The present invention relates to a calibration system and method for wireless charging coils of electric bicycles. The calibration system comprises a transmitter device located on a charging system and a receiver device located on an electric bicycle. The transmitter device comprises a transmitter support, a motion mechanism, a transmitter control unit and a transmitter platform on which a wireless charging coil is installed. The motion mechanism is arranged on the transmitter support and moves up and down, horizontally and vertically thereon. The transmitter platform is installed on the motion mechanism. A signal transmitter is arranged at the center of the transmitter platform to send a calibration signal to the receiver device. The receiver device comprises a receiver support, a receiver control unit and a receiver platform on which a wireless charging coil is installed. The receiver platform is installed on the receiver support. A plurality of signal receivers are arranged at the center and around the receiver platform to receive the calibration signal. The calibration system and method are conducive to calibrating the relative position between the charging system and the wireless charging coil of the electric bicycle and improving the efficiency of wireless charging.

Description

Technical Field

[0001] The invention relates to the technical field of wireless charging of electric bicycles, and in particular to a system and method for calibrating a wireless charging coil of an electric bicycle. Background Art

[0002] With the development of wireless charging technology, more and more electronic products and electric vehicles support wireless charging technology, and the wireless charging system of electric bicycles has also received much attention. The wireless charging system of electric bicycles improves the disadvantages of existing wired charging and has the advantages of convenience, reliability, safety, and strong environmental adaptability. The principle of wireless transmission of electric energy is to form a magnetic field coupling between the transmitting coil and the receiving coil. The magnetic coupling wireless power transmission system requires that the distance between the two coils is appropriate and the positions must be aligned before the power can be efficiently transmitted. If there is a deviation, it will affect the coupling effect and the transmission efficiency.

[0003] Patent CN109050306A aligns the two coils by moving a movable trolley with a transmitting coil, and measures the charging power by continuously changing the height of the trolley by adding low-power charging. Since the space under an electric bicycle is much smaller than the space under an electric car, it is unlikely that the trolley can be accurately moved to the required position in a small space. And for an electric bicycle, it is unlikely to place a trolley below to move the position of the wireless charging coil. Patent CN108973737A uses image processing technology to change the position of the electric car (receiving coil) through human active behavior or automatic parking system to achieve alignment. The technology used is costly and is not applicable to electric bicycles. The user actively changes the position of the electric bicycle according to feedback information, and the accuracy does not meet the requirements. In the existing technical solutions, although the coil alignment can be achieved by mechanically controlling the coil position, this method has mechanical life and cost problems. Since the charging transmitter is embedded underground, maintenance is not very convenient. Summary of the invention

[0004] The object of the present invention is to provide a system and method for calibrating a wireless charging coil of an electric bicycle, which is conducive to calibrating the relative position between the charging system and the wireless charging coil of the electric bicycle, thereby improving the wireless charging efficiency.

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is: a wireless charging coil calibration system for an electric bicycle, comprising a transmitting end device located on the charging system and a receiving end device located on the electric bicycle, the transmitting end device comprising a transmitting end support, a motion mechanism, a transmitting end control unit and a transmitting platform equipped with a wireless charging coil, the motion mechanism is arranged on the transmitting end support, the transmitting platform is installed on the motion mechanism, so as to move up and down, laterally and longitudinally under the drive of the motion mechanism, a signal transmitter is arranged at the center of the transmitting platform to send a calibration signal to the receiving end device, the input and output ends of the transmitting end control unit are electrically connected to the signal transmitter and the motion mechanism respectively; the receiving end device comprises a receiving end support, a receiving end control unit and a receiving platform equipped with a wireless charging coil, the receiving platform is installed on the receiving end support, a plurality of signal receivers are arranged at the center and around the receiving platform to receive the calibration signal, the input end of the receiving end control unit is electrically connected to each signal receiver respectively, and the transmitting end control unit is connected to the receiving end control unit via a wireless network.

[0006] Furthermore, a track groove is provided on the sending end support, and the movement mechanism includes a screw rod arranged in the transverse direction, a screw motor for driving the screw rod to rotate, a slide cooperated with the screw rod to move in the transverse direction of the length direction of the screw rod, an electric push rod for driving the slide rod and the screw rod as a whole to move in the longitudinal direction, and a longitudinal rod arranged in the longitudinal direction. The screw motor is arranged at one end of the screw rod to drive the screw rod to rotate, and the longitudinal rod passes through the slide rod and is rotatably connected with it to support the slide rod and limit the rotation of the slide rod so that the slide rod can only slide in the transverse direction along the screw rod. The electric push rod is arranged at one end of the longitudinal rod and drives the slide rod to move in the longitudinal direction. Rollers are provided at both ends of the screw rod and the longitudinal rod so as to move on the track groove; a lifting mechanism is provided on the slide rod, and the launching platform is installed on the lifting mechanism for up and down movement.

[0007] Furthermore, a track groove is provided on the sending end support, and the movement mechanism includes a transverse movement mechanism, a longitudinal movement mechanism and a slide arranged on the two to perform transverse and longitudinal movement under the drive of the two, the transverse movement mechanism and the longitudinal movement mechanism are arranged on the launching end support to perform transverse and longitudinal movement thereon, a lifting mechanism is provided on the slide, and the launching platform is installed on the lifting mechanism to perform up and down movement; the transverse movement mechanism is mainly composed of a transverse movement rod arranged in the longitudinal direction, a first motor for driving the transverse movement rod to rotate, and a roller driven by the transverse movement rod to rotate to perform transverse movement on the track groove, the transverse movement rod passes through the slide and is rotatably connected to it, so as to drive the slide to perform transverse movement when the transverse movement mechanism is working; the longitudinal movement mechanism is mainly composed of a longitudinal movement rod arranged in the transverse direction, a second motor for driving the longitudinal movement rod to rotate, and a roller driven by the longitudinal movement rod to rotate to perform longitudinal movement on the track groove, the longitudinal movement rod passes through the slide and is rotatably connected to it, so as to drive the slide to perform longitudinal movement when the longitudinal movement mechanism is working.

[0008] Furthermore, a signal receiver B0 is provided at the center of the receiving platform, and four signal receivers B1, B2, B3, and B4 are symmetrically provided at the four quadrants of front, back, left, and right.

[0009] The present invention also provides a method for calibrating an electric bicycle wireless charging coil, comprising the following steps:

[0010] Step S1, when the electric bicycle stops on the charging system, the charging system detects the charging demand, activates the calibration system, and the transmitting end device on the charging system communicates and pairs with the receiving end device on the electric bicycle;

[0011] Step S2, the signal transmitter of the transmitting end device sends a calibration signal;

[0012] Step S3: each signal receiver of the receiving end device receives the calibration signal, and the receiving end control unit calculates the distance from the signal transmitter to each signal receiver according to the ranging principle, obtains the relative position information of the transmitting platform and the receiving platform, and transmits it to the transmitting end control unit through the wireless network;

[0013] Step S4, the control unit of the transmitting end determines whether the relative position information meets the set position requirements. If so, the calibration is completed and charging can be performed. Otherwise, according to the received relative position information, the motion mechanism is controlled to drive the transmitting platform to move up and down, horizontally and vertically at the corresponding distance, and then returns to step S2 to re-measure the distance.

[0014] Furthermore, a signal receiver B0 is provided at the center of the receiving platform, and four signal receivers B1, B2, B3, and B4 are symmetrically provided at the four quadrants of front, back, left, and right. The signal receivers B0, B1, B2, B3, and B4 receive the calibration signal sent by the signal transmitter A0, and the receiving end control unit calculates the distances d0, d1, d2, d3, and d4 from the signal transmitter A0 to the signal receivers B0, B1, B2, B3, and B4 respectively according to the ranging principle, and judges the quadrant position of the receiving platform where the signal transmitter A0 is located accordingly: when d1 and d4 are both smaller than d2 and d3, A0 is located in the first quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d1, and d4; when d1 and d2 are both smaller than d3 and d4, A0 is located in the second quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d1, and d2; when d2 and d3 are both smaller than d1 and d4, A0 is located in the third quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d2, and d3; when d3 and d4 are both smaller than d1 and d2, A0 is located in the fourth quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d3, and d4.

[0015] Compared with the prior art, the beneficial effects of the present invention are: providing an electric bicycle wireless charging coil calibration system and method, utilizing a signal transmitter on a transmitting platform and a signal receiver on a receiving platform to perform distance measurement, obtaining the relative position information of the transmitting platform and the receiving platform, and controlling the transmitting platform to perform corresponding movement accordingly, calibrating the relative position between the charging system and the wireless charging coil of the electric bicycle, realizing the charging position calibration of the wireless charging coil, improving wireless charging efficiency, and having strong practicality and broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a front view of a transmitting end device in a calibration system according to an embodiment of the present invention.

[0017] Figure 2 It is a top view of a transmitting end device in a calibration system according to an embodiment of the present invention.

[0018] Figure 3 It is a front view of a receiving device in the calibration system of an embodiment of the present invention.

[0019] Figure 4 It is a top view of a receiving end device in the calibration system of an embodiment of the present invention.

[0020] Figure 5 It is a flow chart of the implementation of the calibration method of the embodiment of the present invention.

[0021] Figure 6 It is a schematic diagram of the signal transmitter A0 in the third quadrant of the receiving platform in the embodiment of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0023] The present invention provides a wireless charging coil calibration system for an electric bicycle, such as Figure 1 , 2 , 3, and 4, including a transmitter device located on the charging system and a receiving device located on the electric bicycle, the transmitter device includes a transmitter support 1, a motion mechanism, a transmitter control unit 2, and a transmitter platform 4 equipped with a wireless charging coil 3, the motion mechanism is arranged on the transmitter support 1, the transmitter platform 4 is installed on the motion mechanism, so that it can move up and down, horizontally and vertically under the drive of the motion mechanism, and a signal transmitter A0 is arranged at the center of the transmitter platform 4 to send a calibration signal to the receiving device, and the input and output ends of the transmitter control unit 2 are respectively connected to the signal transmitter The receiving end device comprises a receiving end support 5, a receiving end control unit 6 and a receiving platform 8 equipped with a wireless charging coil 7, the receiving platform 8 is installed on the receiving end support 5, a signal receiver B0 is arranged at the center of the receiving platform 8, and four signal receivers B1, B2, B3, B4 are symmetrically arranged at the four quadrants of front, back, left and right to receive calibration signals, the input end of the receiving end control unit 6 is electrically connected to each signal receiver, and the transmitting end control unit 2 is connected to the receiving end control unit 6 through a wireless network.

[0024] In this embodiment, a track groove 9 is provided on the sending end support 1, and the motion mechanism includes a screw rod 10 arranged in the transverse direction, a screw motor for driving the screw rod 10 to rotate, a slide 11 cooperating with the screw rod 10 to move in the transverse direction of the screw rod length direction, an electric push rod 12 for driving the slide 11 and the screw rod as a whole to move in the longitudinal direction, and a longitudinal rod 13 arranged in the longitudinal direction, the screw motor is arranged at one end of the screw rod 10 to drive the screw rod 10 to rotate, the longitudinal rod 13 passes through the slide 11 and is rotatably connected with it to support the slide 11 and limit the rotation of the slide 11, so that the slide 11 can only slide in the transverse direction along the screw rod 10, the electric push rod 12 is arranged at one end of the longitudinal rod 13, and drives the slide 11 to move in the longitudinal direction, and rollers 14 are provided at both ends of the screw rod 10 and the longitudinal rod 13 to move on the track groove; a lifting mechanism 15 driven by the electric push rod is provided on the slide 11, and the launching platform 4 is installed on the lifting mechanism 15 to move up and down.

[0025] The motion mechanism can also have other implementation forms. In another embodiment of the present invention, the transmitting end support is provided with a track groove, the motion mechanism includes a transverse motion mechanism, a longitudinal motion mechanism and a slide arranged on the two to perform transverse and longitudinal motion under the drive of the two, the transverse motion mechanism and the longitudinal motion mechanism are arranged on the transmitting end support to perform transverse and longitudinal motion thereon, the slide is provided with a lifting mechanism, and the launching platform is installed on the lifting mechanism to perform up and down motion; the transverse motion mechanism is mainly composed of a transverse motion rod arranged in the longitudinal direction, a first motor for driving the transverse motion rod to rotate, and a roller driven by the transverse motion rod to rotate to perform transverse motion on the track groove, the transverse motion rod passes through the slide and is rotatably connected to it, so as to drive the slide to perform transverse motion when the transverse motion mechanism is working; the longitudinal motion mechanism is mainly composed of a longitudinal motion rod arranged in the transverse direction, a second motor for driving the longitudinal motion rod to rotate, and a roller driven by the longitudinal motion rod to rotate to perform longitudinal motion on the track groove, the longitudinal motion rod passes through the slide and is rotatably connected to it, so as to drive the slide to perform longitudinal motion when the longitudinal motion mechanism is working.

[0026] The present invention also provides a calibration method corresponding to the above-mentioned electric bicycle wireless charging coil calibration system, such as Figure 5 As shown, the following steps are included:

[0027] Step S1, when the electric bicycle stops on the charging system, the charging system detects the charging demand, activates the calibration system, and the transmitting end device on the charging system communicates and pairs with the receiving end device on the electric bicycle;

[0028] Step S2, the signal transmitter of the transmitting end device sends a calibration signal;

[0029] Step S3: each signal receiver of the receiving end device receives the calibration signal, and the receiving end control unit calculates the distance from the signal transmitter to each signal receiver according to the ranging principle, obtains the relative position information of the transmitting platform and the receiving platform, and transmits it to the transmitting end control unit through the wireless network;

[0030] Step S4, the control unit of the transmitting end determines whether the relative position information meets the set position requirements. If so, the calibration is completed and charging can be performed. Otherwise, according to the received relative position information, the motion mechanism is controlled to drive the transmitting platform to move up and down, horizontally and vertically at the corresponding distance, and then returns to step S2 to re-measure the distance.

[0031] Because different electric vehicle chassis have different heights, such as Figure 5As shown, in this embodiment, the distance between the two wireless charging coils is first measured, and the distance between the two wireless charging coils (i.e., the coupling coefficient) is adjusted to achieve the maximum transmission efficiency of magnetic coupling resonance wireless power transmission. That is, the existing distance is compared with the pre-stored distance of the system, and the height is changed until the requirement is met. Then, horizontal calibration is performed to achieve up-down, horizontal, and vertical calibration.

[0032] In this embodiment, a signal receiver B0 is provided at the center of the receiving platform, and four signal receivers B1, B2, B3, and B4 are symmetrically provided at the four quadrants of front, back, left, and right. The signal receivers B0, B1, B2, B3, and B4 receive the calibration signal sent by the signal transmitter A0. The receiving end control unit calculates the distances d0, d1, d2, d3, and d4 from the signal transmitter A0 to the signal receivers B0, B1, B2, B3, and B4 respectively according to the ranging principle, and judges the quadrant position of the receiving platform where the signal transmitter A0 is located accordingly: when d1 and d4 are both smaller than d2 and d3 , A0 is located in the first quadrant, and the relative position information of the launching platform and the receiving platform is obtained through d0, d1, and d4; when d1 and d2 are both smaller than d3 and d4, A0 is located in the second quadrant, and the relative position information of the launching platform and the receiving platform is obtained through d0, d1, and d2; when d2 and d3 are both smaller than d1 and d4, A0 is located in the third quadrant, and the relative position information of the launching platform and the receiving platform is obtained through d0, d2, and d3; when d3 and d4 are both smaller than d1 and d2, A0 is located in the fourth quadrant, and the relative position information of the launching platform and the receiving platform is obtained through d0, d3, and d4.

[0033] like Figure 6 As shown, take the signal transmitter A0 in the third quadrant as an example. Assuming A0 is in the third quadrant, the ranging is only related to A0, B0, B2, and B3.

[0034] According to the Pythagorean theorem , measure the distance d0 from A0 to B0, and the distance h between the two coils is known. Let a=d0, b=h, and calculate the distance L0a from the projection point A1 of A0 to B0 at the receiving end. Similarly, the distance L2a from the projection point A1 of A0 to B2 can be obtained.

[0035] According to , the distance from B0 to B2 is L02, and the projection points of B0, B2, and A0 form a triangle. Let a=L0a, b=L2a, c=L02, and calculate the distance y from the projection point of A0 to the X axis.

[0036] Similarly, calculate the triangle formed by the projection points of B0, B3, and A0, and calculate the distance from the projection point of A0 to the Y axis, that is, x.

[0037] Re-measure the distance to see if the distance from A0 to B0 is within the allowable range with the calculated height error. If they are the same, activate the wireless charging system; if not, re-measure the distance and change the position until the accuracy requirement is met.

[0038]

[0039] a, b, c represent the three sides of the triangle, S represents the area of ​​the triangle, and h represents the height of the triangle with c as the base.

[0040] In this embodiment, the signal transmitter and the signal receiver may be visible light, laser or other communication devices.

[0041] The RSSI ranging principle is: when positioning, determine the received signal strength, the transmitted signal strength, and the distance between the receiving end and the transmitting end to build a signal strength-distance attenuation model, measure the received signal strength and the transmitted signal strength, and calculate the position of the point to be located.

[0042]

[0043] RSSI is the received power of the wireless signal, P is the transmitted power of the wireless signal, d is the distance between the receiving end and the transmitting end, and n is the environmental attenuation factor. Accurate ranging is achieved by improving the ranging principle.

[0044] The above are preferred embodiments of the present invention. Any changes made according to the technical solution of the present invention, as long as the resulting functions do not exceed the scope of the technical solution of the present invention, belong to the protection scope of the present invention.

Claims

1. An electric bicycle wireless charging coil calibration system, characterized in that: It comprises a transmitting end device located on the charging system and a receiving end device located on the electric bicycle, wherein the transmitting end device comprises a transmitting end support, a motion mechanism, a transmitting end control unit and a transmitting platform equipped with a wireless charging coil, wherein the motion mechanism is arranged on the transmitting end support, and the transmitting platform is installed on the motion mechanism so as to move up and down, laterally and longitudinally under the drive of the motion mechanism, and a signal transmitter is arranged at the center of the transmitting platform so as to send a calibration signal to the receiving end device, and the input and output ends of the transmitting end control unit are electrically connected to the signal transmitter and the motion mechanism respectively; the receiving end device comprises a receiving end support, a receiving end control unit and a receiving platform equipped with a wireless charging coil, and the receiving platform is installed on the receiving end support, and a plurality of signal receivers are arranged at the center and around the receiving platform so as to receive the calibration signal, and the input end of the receiving end control unit is electrically connected to each signal receiver respectively, and the transmitting end control unit is connected to the receiving end control unit via a wireless network; The launching end support is provided with a track groove, and the moving mechanism includes a screw rod arranged in the transverse direction, a screw rod motor for driving the screw rod to rotate, a slide table cooperating with the screw rod to move in the transverse direction of the length direction of the screw rod, an electric push rod for driving the slide table and the screw rod to move in the longitudinal direction as a whole, and a longitudinal rod arranged in the longitudinal direction, the screw rod motor is arranged at one end of the screw rod to drive the screw rod to rotate, the longitudinal rod passes through the slide table and is rotatably connected with it to support the slide table and limit the rotation of the slide table, so that the slide table can only slide in the transverse direction along the screw rod, the electric push rod is arranged at one end of the longitudinal rod, and drives the slide table to move in the longitudinal direction, and rollers are arranged at both ends of the screw rod and the longitudinal rod to move on the track groove; a lifting mechanism is arranged on the slide table, and the launching platform is installed on the lifting mechanism to move up and down; The launch end support is provided with a track groove, and the movement mechanism includes a transverse movement mechanism, a longitudinal movement mechanism and a slide arranged on the two to perform transverse and longitudinal movement under the drive of the two, the transverse movement mechanism and the longitudinal movement mechanism are arranged on the launch end support to perform transverse and longitudinal movement thereon, the slide is provided with a lifting mechanism, and the launch platform is installed on the lifting mechanism to perform up and down movement; the transverse movement mechanism is mainly composed of a transverse movement rod arranged in the longitudinal direction, a first motor for driving the transverse movement rod to rotate, and a roller driven by the transverse movement rod to rotate to perform transverse movement on the track groove. The transverse movement rod passes through the slide and is rotatably connected with it, so as to drive the slide to perform transverse movement when the transverse movement mechanism is working; the longitudinal movement mechanism is mainly composed of a longitudinal movement rod arranged in the transverse direction, a second motor for driving the longitudinal movement rod to rotate, and a roller driven by the longitudinal movement rod to rotate to perform longitudinal movement on the track groove. The longitudinal movement rod passes through the slide and is rotatably connected with it, so as to drive the slide to perform longitudinal movement when the longitudinal movement mechanism is working; A signal receiver B0 is provided at the center of the receiving platform, and four signal receivers B1, B2, B3, and B4 are symmetrically provided at the four quadrants of front, back, left, and right. The electric bicycle wireless charging coil calibration method based on the electric bicycle wireless charging coil calibration system comprises the following steps: Step S1, when the electric bicycle stops on the charging system, the charging system detects the charging demand, activates the calibration system, and the transmitting end device on the charging system communicates and pairs with the receiving end device on the electric bicycle; Step S2, the signal transmitter of the transmitting end device sends a calibration signal; Step S3: each signal receiver of the receiving end device receives the calibration signal, and the receiving end control unit calculates the distance from the signal transmitter to each signal receiver according to the ranging principle, obtains the relative position information of the transmitting platform and the receiving platform, and transmits it to the transmitting end control unit through the wireless network; Step S4, the transmitter control unit determines whether the relative position information meets the set position requirements. If yes, the calibration is completed and charging can be performed. Otherwise, according to the received relative position information, the motion mechanism is controlled to drive the launch platform to move up and down, horizontally and vertically at a corresponding distance, and then returns to step S2 to re-measure the distance. Since different electric vehicle chassis have different heights, the distance between the two wireless charging coils is first measured, and the magnetic coupling resonant wireless power transmission is adjusted to achieve the maximum transmission efficiency by adjusting the distance between the two wireless charging coils; that is, the existing distance is compared with the system pre-stored distance, and the height is changed until the requirement is met; and then horizontal calibration is performed to achieve up and down, horizontal, and vertical calibration; A signal receiver B0 is provided at the center of the receiving platform, and four signal receivers B1, B2, B3, and B4 are symmetrically provided at the four quadrants of front, back, left, and right. The signal receivers B0, B1, B2, B3, and B4 receive the calibration signal sent by the signal transmitter A0. The receiving end control unit calculates the distances d0, d1, d2, d3, and d4 from the signal transmitter A0 to the signal receivers B0, B1, B2, B3, and B4 respectively according to the ranging principle, and judges the quadrant position of the receiving platform where the signal transmitter A0 is located accordingly: when d1 and d4 are both smaller than d2 and d3, A0 A0 is located in the first quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d1, and d4; when d1 and d2 are both smaller than d3 and d4, A0 is located in the second quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d1, and d2; when d2 and d3 are both smaller than d1 and d4, A0 is located in the third quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d2, and d3; when d3 and d4 are both smaller than d1 and d2, A0 is located in the fourth quadrant, and the relative position information between the launching platform and the receiving platform is obtained through d0, d3, and d4.

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