JP2010051089A - Non-contacting power transmission system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-contact power transmission system which enlarges the positional tolerance of an electric power receiver. <P>SOLUTION: The non-contact power transmission system includes an electric power transmitter 1 which transmits electric power, and a movable electric power receiver 2 which receives electric power transmitted from the electric power transmitter 1 without contact, wherein the electric power transmitter 1 is equipped with a transmission coil 11 which transmits a high electric power between itself and the electric power receiver 2, and a communication coil 12 which communicates with feeble power, the electric power receiver 2 is equipped with a receiving coil 21 which receives electric power from the transmission coil 11 of the electric power transmitter 1, a plurality of coil groups 22 and 23 which communicate with the communication coil 12, and a control circuit which detects a coil in active state with the communication coil 12 among the plurality of coil groups. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a contactless power transmission system, and in particular, includes a power transmitter that transmits power and a power receiver that has a function of receiving power in a contactless manner, and the power transmitter so that power is reliably supplied to the power receiver. The present invention relates to a non-contact power transmission system in which a communication coil of a power receiver having an autonomous movement function for communication is arranged.

  Unlike conventional robots, service robots provide services such as guidance / guidance, transport, patrol / tour, etc. with a single robot. The service robot has an autonomous movement function by battery operation.

  Such a service robot must have an automatic charging function for charging the transmitted power in a contactless manner by unattended operation. When performing power transmission by non-contact automatic charging, it is necessary to transmit power to an appropriate transmission target with a safe output. For this reason, conventionally, only when weak power at a level at which the microcomputer on the power transmission side can operate is constantly transmitted, and only when the power receiving side confirms that the power receiving side is an appropriate power transmission partner by the response of the power receiving side microcomputer, The procedure of starting high power transmission from the power transmission side is taken.

  Since this weak radio wave is very weak for safety, the range in which power can be transmitted is limited. However, a certain degree of accuracy is required for automatic connection to the power transmitter, but the accuracy may deteriorate depending on the environment. In a charging mechanism in a conventional mobile robot, although there is a drive unit and a logic unit that require a large amount of current, the mobile robot is not clearly separated and the power supply of the mobile robot receives power It was not necessarily optimal for the control of movement.

  The robot for mobile work described in Patent Document 1 detects that a positional deviation has occurred by the positional deviation detection coil, and by switching and adjusting the charging voltage, a stable charging voltage can be safely applied to the charging coil. It is configured to supply and charge efficiently.

Japanese Patent No. 2658366

However, the mobile work robot described in Patent Document 1 has limited communication tolerance of the position of the power receiver with respect to the power transmitter, and in the unlikely event that it cannot reach the communicable range, No information was available.
Therefore, the present invention provides a non-contact power transmission system that solves the above problems and increases the tolerance of the positional error with the power receiver during docking only by adding an inexpensive circuit. The purpose is to provide.

  A contactless power transmission device according to an embodiment is a contactless power transmission system including a power transmitter that transmits power and a movable power receiver that receives power transmitted from the power transmitter in a contactless manner. The electric device includes a power transmission coil that transmits high power to and from the power receiver, and a communication coil that communicates with weak power, and the power receiver receives power from the power transmission coil to and from the power transmitter. A power receiving coil for receiving power; a plurality of coil groups communicating with the communication coil; and a control circuit for detecting whether any of the plurality of coil groups is in an active state with the communication coil. Prepare.

  In the non-contact power transmission apparatus, the power receiver arranges the two coils so that two coils of the plurality of coil groups can be simultaneously activated.

  In the non-contact power transmission apparatus, the control circuit moves the power receiver according to a simultaneous active state of two coils of the plurality of coil groups.

  According to the contactless power transmission device according to the embodiment, the power receiver includes a power receiving coil that receives power from the power transmitting coil of the power transmitter and a plurality of coil groups that communicate with the communication coil of the power transmitter. The position accuracy of the next docking is increased depending on whether the coil is in an active state with the communication coil of the power transmitter. For the power receiver, install a plurality of communication coils with limited communication range in a common circuit, quantitatively know the amount of positional deviation between the power transmitter and the power receiver, and perform the next docking at an appropriate position Since it is configured to provide information to the power receiver and assist in performing charge control at a safe position, for example, docking is possible in a range that is approximately twice the conventional allowable range of the communication coil.

  In addition, since it is only necessary to add a small coil and a small circuit, it can be manufactured at a lower cost than adding other sensors, and at the same time, it can be confirmed that the target object is an appropriate power transmission target. As a result, a safe and reliable charging operation is possible.

  FIG. 1 is a diagram illustrating a power transmitter that transmits and receives power in a contactless manner according to the first embodiment and a coil arrangement in the power receiver. FIG. 1A is a diagram illustrating a coil arrangement of the power transmitter. ) Is a diagram showing the arrangement of the coil of the power receiver.

  A power transmission device 1 shown in FIG. 1A is provided with a power transmission coil 11, and separately from the power transmission coil 11, a communication coil 12 is provided immediately below the power transmission coil 11. The power receiver 2 shown in FIG. 1B is provided with a power receiving coil 21 and communication coils 22 and 23 at a horizontal position below the power receiving coil 21.

  FIG. 2 is a diagram showing an external appearance when the power transmitter and the power receiver shown in FIG. 1 are service robots. The power transmitter 1 is mounted on a service robot 10 installed on the floor, and the power receiver 2 is mounted on a service robot 20 that can move around the power transmitter 1. The power transmission coil 11 of the power transmitter 1 and the power reception coil 21 of the power receiver 2 are arranged at the same height from the floor in order to transmit power.

  When the power transmitter 1 and the power receiver 2 are docked, if the communication coil 12 of the power transmitter 1 and the communication coil 22 or 23 of the power receiver 2 communicate with each other, how much the position of the power receiver 2 in the left-right direction should be corrected. In other words, the communication coil 12 and the communication coils 22 and 23 are arranged at the same height from the floor so that it can be understood how much the power receiver 2 should be moved in the left-right direction and to increase communication sensitivity. Moreover, although the communication coil 12 is mounted on the power transmitter 1 and the two communication coils 22 and 23 are mounted on the power receiver 2, the external dimensions of the power transmitter 1 and the power receiver 2 are not changed.

  When only one communication coil is provided, it is unclear how much the moving direction of the power receiver 2 is shifted between the power transmitter 1 and the power receiver 2 during docking. However, as described above, By providing the two communication coils 22 and 23, it is possible to check the docking accuracy in a range that is approximately twice that in the case where the number of communication coils of the power receiver 2 is single.

  As shown in FIG. 1B, communication within the power receiver 2 is performed so that the shift in the moving direction of the power receiver 2 during docking becomes an index of a range that can be readjusted within a range of ± 38 mm = ± (20 + 9 + 9) mm. Coils 22 and 23 are installed.

  When the communication coils 22 and 23 are installed as shown in FIG. 1B and communication between the communication coil 12 and the communication coil 22 or 23 is established, for example, communication between the communication coil 12 and the communication coil 22 is performed. Is established and communication between the communication coil 12 and the communication coil 23 is not established, the power receiver 2 unconditionally moves 20 mm to the right at the next docking, and communication between the communication coil 12 and the communication coil 22 is established and communication is not established. When communication between the coil 12 and the communication coil 23 is established, the power receiver 2 is designed to unconditionally move 20 mm in the left direction at the next docking.

  That is, the communication coils 22 and 23 can communicate within a range of ± 20 mm in the horizontal direction, and the power transmission coil 11 and the power reception coil 21 are guaranteed maximum power transmission and reception within a range of ± 20 mm. In other words, the power receiving coil 21 is designed so that the maximum power can be transmitted if communication is possible. Therefore, the communicable range between the communication coil 12 and the communication coils 22 and 23 is a range (± 20 mm) in which full power can be transmitted.

  As described above, by providing the communication coils 22 and 23, by detecting which of the communication coils 12 and the communication coil of the plurality of communication coils 22 and 23 is optimal, It is possible to know the correction direction and the correction amount of the position with respect to the movement direction of the power receiver 2 at the next docking (reconnection).

  FIG. 3 is a diagram showing a second embodiment in which the distance between two communication coils is shortened in the arrangement of the communication coils in the power receiver shown in FIG. FIG. 3 shows an example in which two communication coils 22 and 23 are arranged so that the two communication coils 22 and 23 can be in an active state at the same time.

  The two communication coils 22 and 23 are arranged so that there is a portion common to each communication range of the two communication coils 22 and 23, that is, there are overlapping portions (OVR1 and OVR2 in FIG. 3). According to the second embodiment, it is possible to know an accurate shift amount by confirming that two communication coils are simultaneously active.

  FIG. 4 is a block diagram showing an outline of a circuit configuration in the power receiver according to the first and second embodiments. The control circuit 40 shown in FIG. 4 detects whether any of the plurality of power receiving devices 402, in this example, the three communication coils 422, 423, and 424 is in an active state, and charges the charging device 45. It is. In addition, the control circuit 40 notifies the robot of the simultaneous active state of two of the plurality of coils 422 to 424 and moves the power receiver 402.

  In the control circuit 40, the optimum phase / voltage recognition circuit 41 that receives signals from the three communication coils 422 to 424 can be used in common for the received signals. Can be configured with only a small coil and a small circuit. Therefore, it is possible to manufacture the power receiver 402 at a lower cost than adding a sensor for detecting the power transmitter 401 to the power receiver 402.

  The three communication coils 422 to 424 of the power receiver 402 are provided at equal intervals at the same height as the height of the communication coil 412 of the power transmitter 401 from the floor. Compared with the power receiver 2 provided with two communication coils shown in FIG. 3, the power receiver 402 provided with three communication coils shown in FIG. 4 is the power receiver 402 when the power transmitter 401 and the power receiver 402 are docked. Increase position accuracy in the moving direction.

  Since the plurality of communication coils 422 to 424 are provided in the power receiver 402 as shown in FIG. 4, the docking accuracy is improved, and it can be confirmed whether the power receiver 402 is an appropriate power transmission target. Safe and reliable charging to the charging device 45 is possible.

  FIG. 5 is a time chart showing an output voltage waveform of the optimum phase recognition circuit shown in FIG. In FIG. 5, the horizontal axis represents time, and the vertical axis represents the output signal of the optimum phase recognition circuit 41 when receiving signals from two communication coils and the input signal to the coil transmission circuit 42.

  In FIG. 5, the voltage waveform 51 indicates the voltage waveform of the signal received by the communication coil 422, and the voltage waveform 52 indicates the voltage waveform of the signal received by the communication coil 423. In FIG. 5, it can be seen that the voltage waveform 51 is larger in amplitude than the voltage waveform 52 by AS (Amp Shift). This indicates that the communication coil 422 is located closer to the communication coil 412 of the power receiver 401 than the communication coil 423.

  5 that the voltage waveform 51 and the voltage waveform 52 have a phase shift PS (Phase Shift). When the PSs match, the distances are adjusted so that they are known to be the same distance and active simultaneously.

  In FIG. 4, the microcomputer 43 receives outputs from the optimum phase / voltage recognition circuit 41 and the coil transmission circuit 42 and controls to move a robot (not shown) on which the power receiver 402 is mounted.

  The switch 44 supplies electric power supplied from the power transmitter 401 to the robot under the control of the microcomputer 43.

(Appendix 1)
A contactless power transmission system comprising a power transmitter for transmitting power and a movable power receiver for receiving the power transmitted from the power transmitter in a contactless manner,
The power transmitter includes a power transmission coil that transmits high power and a communication coil that communicates with weak power with the power receiver,
The power receiver includes a power receiving coil that receives power from the power transmitting coil with the power transmitter, a plurality of coil groups that communicate with the communication coil, and any coil of the plurality of coil groups Comprising a control circuit for detecting whether or not the communication coil is in an active state,
Contactless power transmission system.

(Appendix 2)
The power receiver has the two coils arranged so that two coils of the plurality of coil groups can be simultaneously active.
The contactless power transmission system according to appendix 1.

(Appendix 3)
The control circuit moves the power receiver according to a simultaneous active state of two coils of the plurality of coil groups.
The contactless power transmission system according to appendix 1 or 2.

It is a figure which shows arrangement | positioning of the coil in the power transmitter and power receiver which transmit / receive electric power based on 1st Embodiment, and (A) is a figure which shows arrangement | positioning of the coil of a power transmitter, (B) is receiving. It is a figure which shows arrangement | positioning of the coil of an electric appliance. It is a figure which shows the external appearance in case the power transmission device and power receiving device which are shown in FIG. 1 are service robots. It is a figure which shows 2nd Embodiment which shortened the distance between two communication coils in arrangement | positioning of the communication coil in the power receiving device shown to (B) of FIG. It is a block diagram which shows the outline | summary of the circuit structure in the power receiving device which concerns on 1st and 2nd embodiment. 5 is a time chart showing an output voltage waveform of the optimum phase recognition circuit shown in FIG. 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Power transmitter 2 Power receiver 11 Power transmission coil 12, 22, 23 Communication coil 21 Power reception coil 40 Control circuit

Claims (3)

A contactless power transmission system comprising a power transmitter for transmitting power and a movable power receiver for receiving the power transmitted from the power transmitter in a contactless manner,
The power transmitter includes a power transmission coil that transmits high power and a communication coil that communicates with weak power with the power receiver,
The power receiver includes a power receiving coil that receives power from the power transmitting coil with the power transmitter, a plurality of coil groups that communicate with the communication coil, and any coil of the plurality of coil groups Comprising a control circuit for detecting whether or not the communication coil is in an active state,
Contactless power transmission system. The power receiver has the two coils arranged so that two coils of the plurality of coil groups can be simultaneously active.
The contactless power transmission system according to claim 1. The control circuit moves the power receiver according to a simultaneous active state of two coils of the plurality of coil groups.
The non-contact power transmission system according to claim 1 or 2.

Images