JP6092678B2 - Non-contact power transmission system - Google Patents

Description

  The present invention relates to a non-contact power transmission system that performs non-contact (wireless) power transmission between a power transmission device and a power reception device, and in particular, a power transmission coil that constitutes a power transmission resonator of the power transmission device and a power reception resonator of the power reception device. It is related with the non-contact electric power transmission system for arrange | positioning the receiving coil which comprises A through a partition, and performing the electric power transmission stably using the resonance state of a coil.

  Non-contact power transmission methods include electromagnetic induction using electromagnetic induction, resonant power supply via electric field or magnetic field resonance, microwave power transmission using radio waves, and laser power transmission using electromagnetic waves (light) in the visible light region. It has been. Among them, the electromagnetic induction method has already been put into practical use. This has the advantage that it can be realized with a simple circuit (transformer system), but there is also a problem that the transmission distance is short. Therefore, a resonance power feeding method that transmits power up to several meters ahead using resonance is proposed, and product development using this technology is being promoted mainly by electrical manufacturers and automobile manufacturers.

  On the other hand, large-capacity data communication by radio of mobile devices such as mobile phones and PDAs inevitably requires a large amount of power, which is a demand for expansion of battery capacity. However, it is difficult to secure a sufficient battery capacity with current lithium ion batteries. Non-contact power transmission is attracting attention as a supplement. From this point of view, it is expected that the development and commercialization of high-capacity information communication and wireless power transmission will progress in the future.

  Here, when considering the power transmission by the resonance power feeding method, there are the following problems. Power transmission is performed by electromagnetic coupling of a power transmission device that receives power from an AC outlet or system power and a power reception coil of a power reception device to which a load is connected, but the coupling coefficient k value between both coils is small, while the Q value is It is characterized by increasing. When a coil having a high Q value is used, a high voltage is generated at both ends of the coil, and further, when a peaky system is caused by a high Q, it is difficult to follow various adjustment mechanisms.

  In particular, when a mismatch occurs between the power transmission device and the power reception device due to temperature fluctuation, or when a metal foreign object approaches the power transmission device and the power reception device, it is necessary to quickly operate the resonance adjustment mechanism. If not optimized, unnecessary radiation increases, and in the worst case, the device itself may be damaged by reflected power. For this reason, it is necessary to solve the above-described problem related to the resonance adjustment mechanism by using some means while taking advantage of the long-distance power transmission performance which is the greatest merit of the resonance power supply.

  For example, the power transmission device of the system disclosed in Patent Document 1 includes a communication unit in addition to a power transmission unit that transmits power in a contactless manner, and starts power transmission in an external power transmission device received by the communication unit in a certain time frame. Whether or not power transmission is possible is determined based on the information indicating. It is configured to selectively transmit power based on the determination result. According to this method, even when there are a plurality of power transmission devices, a system capable of transmitting power from one power transmission device to one power reception device without receiving interference from other power transmission devices. Can be provided.

Japanese Patent No. 045557045

  In the case of the configuration disclosed in Patent Document 1, it takes a certain amount of time for the communication unit to detect and determine whether power transmission is necessary or stopped and to operate the adjustment mechanism. For this reason, there is a problem that it cannot respond at a sufficiently high speed when the apparatus is turned on / off, or when other load fluctuations or sudden abnormalities occur.

  In particular, in contactless power transmission using the resonance state of the power transmission coil and the power reception coil, a large resonance power may be generated if an error occurs in the adjustment, and thus measures to prevent damage to the power reception device are required.

  Therefore, the present invention is a non-contact power transmission system capable of always stably performing high-efficiency non-contact power transmission utilizing the resonance state of the coil in response to a load fluctuation or abnormality at a sufficient speed. The purpose is to provide.

  A non-contact power transmission system of the present invention includes a power transmission device including a power transmission coil and a power transmission circuit including a power transmission coil and a power transmission circuit to which a capacitor corresponding to a resonance capacitor is added, and a power reception device to which a capacitor corresponding to a resonance capacitance is added. A power receiving unit including a coil and a power receiving circuit and a power receiving device having a power receiving communication unit, and non-contact power transmission from the power transmitting device to the power receiving device via a partition wall by an action between the power transmitting coil and the power receiving coil. And supplying power to the external load, and controlling the power transmission based on information by communication between the power transmission communication unit and the power reception communication unit.

In order to solve the above-described problem, in the non-contact power transmission system according to the present invention, the power receiving device includes a first power storage unit including a battery or a capacitor, and the first power storage unit is provided by power transmitted from the power transmission device. Control is performed to charge the charging rate within a predetermined range so that the power of the first power storage unit can be supplied to the external load, and execution or stop of the power transmission with respect to the power transmission device according to the control is performed by the communication. When an external load to which power is supplied from the power receiving device changes from power OFF to ON, power at power-on is supplied from the first power storage unit, and then commanded by the communication Power supplied from the power transmission device is supplied to the external load .

  According to the non-contact power transmission system having the above configuration, based on the auxiliary function of the battery installed in the power receiving apparatus, it can cope with load fluctuations and abnormalities at a sufficient speed, and uses the coil resonance state for high efficiency. Contact power transmission can always be stably operated.

The perspective view which shows typically the non-contact electric power transmission system in Embodiment 1. FIG. Side view of the contactless power transmission system Block diagram showing a power transmission device constituting the non-contact power transmission system Block diagram showing a power receiving device constituting the non-contact power transmission system Flow diagram showing basic operation of the wireless power transmission system Flow chart showing the operation of the non-contact power feeding determination step in the basic operation The flowchart which shows the operation | movement of the step of the other non-contact electric power feeding determination in the basic operation Block diagram showing a power transmission device constituting the non-contact power transmission system in the second embodiment The perspective view which shows typically the non-contact electric power transmission system in Embodiment 3 of this invention. Side view of the contactless power transmission system Block diagram showing a relay device constituting the non-contact power transmission system The perspective view which shows the modification of the non-contact electric power transmission system typically The perspective view which shows typically the other modification of the non-contact electric power transmission system

  The non-contact power transmission system of the present invention can take the following forms based on the above configuration.

  That is, when an external load to which power is supplied from the power receiving device is changed from power OFF to ON, power at power-on is supplied from the first power storage unit, and then the commanded by the communication is performed. Electric power from the power transmission device is supplied to the external load. When the load power is turned on, power is suddenly required due to an inrush current or the like. Therefore, smooth power supply is possible by supplying power from the power transmission device through the communication unit while providing instantaneous power when the power is turned on by the first power storage unit mounted on the power receiving device.

  In addition, when power transmission from the power transmission device is stopped based on the communication from the power receiving device, control is performed so that transmission power until the power transmission is stopped is accumulated in the first power storage unit. Thereby, until electric power stops completely, electric power can be stored in the 1st electrical storage part, and damage to a power transmission device or a power receiving device can be prevented. This is a configuration that copes with the fact that a certain amount of time is required for the control for stopping the non-contact power transmission by communication when the power source of the load is changed from the on state to the off state. Even when a sudden abnormality is detected, the same power stop is performed, so that such a situation can be dealt with.

  In addition, the power receiving device performs control to charge the first power storage unit to a charging rate within a predetermined range by the power transmitted from the power transmitting device, and accordingly, performs or stops the power transmission to the power transmitting device. Command by the communication. In this case, the power receiving device controls the charge / discharge state of the first power storage unit within a range of a charging rate of 20 to 90%.

  The power transmission device has a function of detecting the presence or absence of the power receiving device, and has a function of stopping power transmission and outputting a notification signal when the loss of the power receiving device is detected. Alternatively, the power receiving device stores information on the number of times of charging and temperature as information on a charge / discharge state of the first power storage unit, and compares the information with a list stored in advance in the power receiving device, If it does not meet the regulations, it has a function to output a notification signal. In these cases, the power transmission communication unit outputs the notification signal by an electric signal, sound, or light by a device provided in the power transmission device, and other than the power transmission device through communication to another communication device. It has a function to report to the user by the device.

  In addition, the power receiving apparatus includes a relay power receiving unit having a function corresponding to the power receiving unit and a relay power transmitting unit having a function corresponding to the power transmitting unit, and transmits power transmitted from the power transmitting device to the relay. The power reception unit receives the power in a contactless manner, and the received power is transmitted to the power reception device in a contactless manner by the relay power transmission unit.

  The power transmission device includes a second power storage unit including a battery or a capacitor, and can store at least a part of the power generated by the power transmission circuit in the second power storage unit. In this case, the power transmission device controls the charge / discharge state of the second power storage unit within a range of a charge rate of 20 to 90%. In addition, power can be supplied from the second power storage unit to the power receiving device, and the power supply is controlled by the communication. In addition, when power transmission from the power transmission device is stopped based on the communication from the power reception device, the power remaining in the power transmission circuit until the power supply from the external power source to the power transmission device is stopped is 2 Control to store in the power storage unit.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
The non-contact power transmission system in Embodiment 1 is schematically shown in a perspective view in FIG. 1A. FIG. 1B is a side view thereof. This system includes a pair of one power transmission device 1 and one power reception device 2. The power transmitting device 1 and the power receiving device 2 are installed to face both surfaces of the partition wall 3 and have a configuration suitable for power transmission with the partition wall 3 interposed therebetween.

  The power transmission device 1 includes a power transmission unit 4 and a power transmission communication unit 5 and can be equipped with a battery 6 (or a capacitor; the same applies hereinafter). The power receiving device 2 includes a power receiving unit 7 and a power receiving communication unit 8, and a battery 9 (or a capacitor; the same applies hereinafter) is mounted. The power output from the power receiving unit 7 is supplied to the external load 10.

  A feature of the present invention is that only the power receiving device 2 includes the battery 9 as a power storage unit, or both the power transmission device 1 and the power receiving device 2 include the batteries 6 and 9 as power storage units. Whether the battery is mounted only on the power receiving side or both can be set according to the stability of the non-contact power feeding, the load state, the environment in which the apparatus is installed, or the needs. The specific configuration shown below shows an example in which the battery 9 is provided only in the power receiving device 2.

  FIG. 2A shows a block diagram of the power transmission device 1. The power transmission unit 4 includes a power transmission coil 11 and a power transmission circuit 12. A capacitor (not shown) is added as a resonance capacitor to the power transmission coil 11 to constitute a power transmission resonator. In the power transmission circuit 12, the power from the external power supply 13 is stabilized by a power factor correction circuit (PFC) 14 added as necessary, and supplied to DD (DC-DC) converters 15 and 16.

  The DC power whose voltage level has been optimized by the DD converter 15 is converted to AC power by the inverter 17, and AC power that has passed through the low-pass filter 18 for approaching a sine wave is applied to the power transmission coil 11. The frequency of the AC power is set so as to substantially match the resonance frequency of the power transmission resonator including the inductance of the power transmission coil 11 and the resonance capacitance (capacitance of the capacitor). Also, the pulse width and pulse timing of the AC power output from the inverter 17 are adjusted by the Dubai rubber bar 19. This is to prevent the switching loss of the FET (field effect transistor) constituting the inverter 17 from occurring as much as possible so that the resonance frequency is obtained after passing through the filter 18.

  On the other hand, the DC power whose voltage level is optimized by the DD converter 16 is supplied to the power transmission communication unit 5. The operation of the above elements is controlled by the control unit 20.

  FIG. 2B shows a block diagram of the power receiving device 2. The power receiving unit 7 includes a power receiving coil 21 and a power receiving circuit 22. A capacitor (not shown) is added as a resonance capacitor to the power receiving coil 21 to constitute a power receiving resonator. The resonance frequency of the power receiving resonator is set so as to substantially match the resonance frequency of the power transmission resonator.

  The AC received power transmitted from the power transmission coil 11 to the power reception coil 21 is converted into direct current by the rectifier 23 of the power reception circuit 22 and supplied to the DD converters 24 and 25. The electric power adjusted to an appropriate voltage level for the battery and the capacitor by the DD converter 24 is supplied to the load 10 and the charging circuit 27 via the protection circuit 26. The protection circuit 26 and the charging circuit 27 appropriately control charging / discharging of the battery 9 (or a capacitor, the same applies hereinafter), and supplies power to the load 10.

  On the other hand, the DC power whose voltage level has been optimized by the DD converter 25 is supplied to the power receiving communication unit 8. The operation of the above elements is controlled by the control unit 28. The memory 29 is provided to store information such as the number of times of charging and temperature as information on the charge / discharge state of the battery 9.

  The power transmission communication unit 5 and the power reception communication unit 8 provide a communication function between the power transmission device 1 and the power reception device 2. Although illustration is omitted, the power transmitting device 1 and the power receiving device 2 indicate whether or not power transmission is appropriately performed, whether or not the state of the battery is appropriately managed, and whether there is any other abnormal state Is provided. And the state which those detection functions provide is monitored by mutual communication. Control according to the monitor is performed by the control units 20 and 28. Also notify the user if necessary.

  The function for detecting the abnormal state includes a function for the power transmission device 1 to detect the presence or absence of the power reception device 2. The presence / absence of the power receiving device 2 can be detected by, for example, the presence / absence of a response from the power receiving communication unit 8 or the reflected power returned to the power transmitting unit.

  Next, the operation of the non-contact power transmission system having the above configuration will be described. FIG. 3A is a flowchart showing the basic operation of this non-contact power transmission system, and FIG. 3B is a flowchart showing the operation of the non-contact power feeding determination step in the basic operation shown in FIG. 3A.

  When the power of the non-contact power transmission system is turned on (step S1), the system confirmation mode is set (step S2), and it is determined whether or not the charging rate of the battery 9 is sufficient in the power receiving device 2 (step S3). If it is not sufficient, a power supply is requested by communication from the power receiving communication unit 8 to the power transmission communication unit 5, and the control unit 20 of the power transmission unit 4 controls the non-contact power supply determination (step S4).

  The non-contact power supply determination in step S4 is performed as shown in FIG. 3B. First, with the transition from step S3, the power transmission device 1 starts non-contact power transmission (step S110), and then determines whether or not the non-contact power is sufficient (step S120). If it is sufficient, the process returns to step S3, and the contactless power transmission is continued while repeating the contactless power feeding determination (step S4) until the charging rate of the battery 9 reaches the set level.

  If the non-contact power is not sufficient in step S120, it is determined whether or not it is within the range of the non-contact power transmission adjustment function (step S130). If it is within the range, the adjustment is performed, the process returns to step S110, and the determination in step S120 is repeated. If it is not within the range, power transmission is stopped (step S140), and an alarm is output (step S150).

  When the charging rate of the battery 9 is sufficient in step S3 of FIG. 3A, the system shifts to the system operation mode (step S5), and the external load 10 connected to the power receiving device 2 is in the operation ON state (that is, consumes current). Is determined) (step S6). This determination is performed by the control unit 28 of the power receiving device 2, and when the load 10 is in an operation OFF state (standby), it is determined whether or not the charging rate of the battery 9 is sufficient in the power receiving device 2 (step S7). .

  If the charging rate of the battery 9 is not sufficient (step S7, No), communication for requesting power supply from the power receiving communication unit 8 to the power transmission communication unit 5 is performed, and the control unit 20 of the power transmission unit 4 controls non-contact power feeding determination. Is performed (step S8). The operation of the contactless power feeding determination in step S8 is the same as that in step S4. However, if the non-contact power is sufficient, the process returns to step S6, and the operation of determining whether the load 10 is on or off is repeated. Even in the case where the charging rate of the battery 9 is sufficient in step S7, the process returns to step S6, and the operation for determining whether the operation of the load 10 is ON or OFF is repeated.

  If the load 10 is in the operation ON state in step S6, power is supplied from the battery 9 to the load 10 (step S9), and the battery 9 provides instantaneous power when the power is turned on. Next, information that the load 10 is in operation ON is transmitted to the power transmission device 1 via the communication units 8 and 5 to start non-contact power transmission (step S10). Further, it is determined whether or not the non-contact power is sufficient (step S11).

  When the non-contact power is not sufficient (step S11, No), the non-contact power supply determination is performed (step S12). As shown in FIG. 3C, this non-contact power feeding determination is a part of the non-contact power feeding determination in step S4. Therefore, the same reference numerals are assigned to the same steps, and description thereof is omitted. If the non-contact power is sufficient in step S11, it is determined whether the operation of the load 10 is ON / OFF (step S13). If the load 10 is on, the process returns to step S10 and the non-contact power transmission is continued. . If the load 10 is off, the process returns to step S7 and the above-described operation is repeated.

  Operations in various states of the non-contact power transmission system based on the above flow will be described below.

[1. When the load 10 is in the operation OFF state]
For example, this is a case where the power of the device that is the load 10 is not turned on. In this case, since no power is consumed other than the standby power, the battery 9 (or capacity, the same applies hereinafter) incorporated in the power receiving device 2 supplies only the power consumed by the standby power. That is, when the charging rate of the battery 9 is lowered from a desired value due to standby power, a signal for supplying power from the power transmission unit 4 via the power transmission communication unit 5 by operating the communication function of the power reception communication unit 8. Send. When the charging rate of the battery 9 reaches a desired state, communication is performed in the same manner, stop control is performed, and power transmission is stopped.

[2. When load 10 is in operation ON state]
When the power supply of the load 10 is turned on, electric power is required rapidly due to an inrush current or the like. For this reason, the battery 9 mounted on the power receiving device 2 supplies power from the power transmitting device 1 through the communication unit while providing instantaneous power when the power is turned on. If the charging rate of the battery 9 is sufficient, it is possible to continue the electric power from the battery 9 until the charging rate falls below the set charging rate.

[3. When the power supply of the load 10 changes from the on state to the off state]
Control is performed to stop power supply from the power transmission device 1 through the power receiving communication unit 8. However, the rapid stop operation may put a burden such as a reverse voltage on the apparatus. On the other hand, a certain amount of time is required for communication control until the power supply is completely stopped. Therefore, a function for storing electric power in the battery 9 is provided until the electric power supply is completely stopped. Further, when the charging rate of the battery 9 is lower than the set charging rate, the non-contact power transmission is continued until the battery 9 reaches a sufficient charging rate.

[4. When a sudden abnormality is detected]
The power stop similar to the above-mentioned item 3 is performed. However, when the power receiving device 2 is lost for some reason, the power supplement as described above by the battery 9 mounted on the power receiving device 2 does not function. In this case, since a very large voltage is generated in the power transmission coil 11, this is monitored and an alarm signal is immediately transmitted from the power transmission device 1. In addition, a communication device in the hands of a system administrator (or user) prepared separately from the non-contact power transmission system is configured so that the alarm signal is received, and the system administrator immediately knows the abnormality. To be able to.

  Next, the functions and settings of the individual elements described above will be described. The state of the battery 9 is controlled so that the charging rate is maintained within a range of 20 to 90%, more preferably 40% to 60%. This prevents the battery characteristics from degrading rapidly when the charging rate exceeds 90%. On the other hand, if the charging rate is lower than 20%, the necessary power is supplied from the battery when necessary. The purpose is to prevent this because it becomes impossible.

  When the load 10 is on standby (when only standby power is consumed), power is supplied from the battery 9 to the load until the charging rate approaches the lower limit. When the load 10 changes from ON to OFF, power is supplied until the charging rate approaches the upper limit. As a result, the number of times of charging / discharging the battery or capacitor can be minimized, so that the product life can be extended by minimizing the deterioration of the characteristics of the battery or capacitor. In particular, when charging the battery, control is performed by a temperature monitor, a timer, or the like charged in the apparatus so as not to be performed when the temperature is low.

  Information on the number of times of charging and temperature is stored in the memory 29 in the power receiving device 2 as information on the charge / discharge state of the battery 9. A configuration in which the information is compared with a list incorporated in the power transmission communication unit 5 and the power reception communication unit 8 in advance, and when the information is not included in the list, a notification function to the user or the system administrator is quickly activated. And

  In particular, it is desirable that the power transmission communication unit 5 has a notification function using sound and light in its own device and can communicate with a communication device other than the non-contact power transmission system. As a result, a function is provided to ensure that the user is notified. Furthermore, when the power receiving apparatus 2 is lost, it is desirable to make settings on the hardware software so that a power transmission stop command is immediately transmitted and at the same time the notification signal is preferentially output.

<Embodiment 2>
FIG. 4 is a block diagram illustrating a configuration example of the power transmission device 1a configuring the contactless power transmission system according to the second embodiment. In the power transmission device 1a, the power transmission device 1 according to the first embodiment is mounted with a battery 6 (or a capacitor), and a configuration for that is added. Other configurations are the same as those of the first embodiment, and the same elements are denoted by the same reference numerals and the description thereof will not be repeated.

  Since the battery 6 is mounted on the power transmission device 1a, a protection circuit 31 to which power is supplied from the DD converter 30 is added. The charging circuit 32 charges the battery 6 with electric power via the protection circuit 31. Further, it has a function of transmitting non-contact power from the protection circuit 31 via the inverter 17, the filter 18, and the power transmission coil 11. These operations are controlled by the control unit 33. In addition, a memory 34 that stores information on the number of times of charging and temperature is provided and used for the operation of the control unit 33.

  The basic operation of the non-contact power transmission system using the power transmission device 1a is the same as that of the first embodiment, but operations unique to the present embodiment in various states will be described below.

[1. When the load 10 is in the operation OFF state]
When the charging rate of the battery 9 of the power receiving device 2 decreases from the set level due to the standby power of the load 10, the power receiving communication unit 8 communicates with the power transmission communication unit 5 to supply power from the battery 6 mounted on the power transmission device 1a. Then, power can be supplied to the battery 9 of the power receiving device 2 in a non-contact manner via the power transmitting coil 11 and the power receiving coil 21.

[2. When load 10 is in operation ON state]
Instead of supplying power from the external power source 13 or simultaneously with the external power source 13 during the operation of supplying power from the power transmitting device 1a, power is supplied from the battery 6 mounted on the power transmitting device 1a, and the power transmitting coil 11 and the power receiving coil The electric power can be supplied to the power receiving device 2 through the contact 21 in a non-contact manner.

[3. When the power supply of the load 10 changes from the on state to the off state]
The power remaining in the power transmission circuit 12a until the power supply from the external power supply 13 is completely stopped is stored as power in the battery 6 mounted in the power transmission device 1a. The power remaining in the power receiving circuit 22 is stored as power in the battery 9 mounted in the power receiving device 2.

[4. When a sudden abnormality is detected]
Similarly to the above-mentioned third term, the power remaining in the power transmission circuit 12a until the power supply from the external power supply 13 is completely stopped is stored as power in the battery 6 mounted in the power transmission device 1a. Alternatively, the power remaining in the power receiving circuit 22 is stored as power in the battery 9 mounted in the power receiving device 2.

  Regarding the function and setting of each element, the power transmission device 1a is also provided with the battery management function of the power receiving device 2 described in the first embodiment.

  Note that a non-contact power transmission system is configured by combining a plurality of power transmission devices 1 or 1a and power reception devices 2 constituting the non-contact power transmission system of Embodiments 1 and 2 above, or both of them. can do. Also in this case, the power receiving device always includes a battery or a capacitor, and the power transmitting device can select a configuration in which the battery or the capacitor is mounted or a configuration in which the battery or the capacitor is not mounted.

  However, the communication function to be installed is advanced, and not star-to-point communication but star-type communication using a power transmission device as a host, or mesh communication in which a power reception device also performs mutual communication, and the like. Accordingly, in addition to communication with the power transmission device, the power reception devices can cooperate with each other to perform non-contact power transmission, battery management, and notification to the user.

<Embodiment 3>
A non-contact power transmission system according to Embodiment 3 is schematically shown in a perspective view in FIG. 5A. FIG. 5B is a side view thereof.

  This system has a configuration in which a power relay device 40 arranged at an intermediate position is provided for a pair of the power transmission device 1 and the power reception device 2. The power transmission device 1 and the power receiving device 2 are installed to face both surfaces of the partition wall 3a, and transmit power with the partition wall 3a interposed therebetween. The power relay device 40 is embedded in the partition wall 3a and includes a power transmission / reception unit 41, a relay communication unit 42, and a battery 43 (or a capacitor, the same applies hereinafter).

  The power relay device 40 has a power transmission function and a power reception function as an integral unit. That is, the power transmission / reception unit 41 includes a relay power reception unit and a relay power transmission unit, receives power transmitted from the power transmission device 1, and transmits the power to the power reception device 2 in a contactless manner.

  The configuration of the power relay device 40 includes a relay power reception unit 41a, a relay power transmission unit 41b, a communication unit 42, and a battery 43, as shown in the block diagram of FIG. The relay power reception unit 41a and the relay power transmission unit 41b constitute the power transmission / reception unit 41 illustrated in FIG. 5A. The configurations of the power reception circuit 22a of the relay power reception unit 41a and the power transmission circuit 12a of the relay power transmission unit 41b are substantially the same as those of the power reception circuit 22 and the power transmission circuit 12a in the first embodiment shown in FIGS. 2B and 2A. Therefore, the operations of the relay power reception unit 41a and the relay power transmission unit 41b are basically the same as the operations of the power reception unit 7 and the power transmission unit 4, and the same elements are denoted by the same reference numerals and the description is simplified. To do.

  The operation of the power relay device 40 is as follows. First, the power transmitted from the power transmission device 1 is received in a non-contact manner by the power receiving coil 21 of the relay power receiving unit 41a, and is stored in the battery 43 through the rectifier 23, the DD converter 24, the protection circuit 26, and the charging circuit 27. . Alternatively, DC power that has passed through the rectifier 23, the DD converter 24, and the protection circuit 26 is supplied to the inverter 17 of the relay power transmission unit 41b. The AC power output from the inverter 17 is output toward the power receiving device 2 via the filter 18 and the power transmission coil 11.

  At this time, since the battery 43 can be used as a DC power source in the power relay device 40, a power factor correction circuit or the like is unnecessary in the relay power transmission unit 41b. Furthermore, since the power source can be more stable than the external power source, it can be directly converted into AC power via the inverter 17.

  Unlike the configuration of FIG. 5A, the power relay device 40 can relay power when there is one power transmission device and a plurality of power reception devices. Even when there are a plurality of power transmission devices and one power reception device, or when there are a plurality of power transmission devices and power reception devices, it is possible to function as a power relay point. Mesh communication that performs mutual communication including the power transmission device, the power relay device 40, and the power reception device may be performed, and contactless power transmission, battery management, and notification to the user may be performed in cooperation with each other.

  A modification of the non-contact power transmission system using the power relay device 40 similar to the above configuration is schematically shown in a perspective view in FIG. In this example, the power transmission device 1 and the power relay device 40 are installed on both surfaces of the partition wall 3, and the power reception device 2 a is disposed away from the partition wall 3. The arrangement of this configuration is substantially the same as that in FIG. 5A, and the same effect can be obtained. The power receiving device 2a has the same configuration as that of the power receiving device 2 described above, but includes a load 10 (not shown).

  FIG. 8 schematically shows another modification of the non-contact power transmission system. In this example, similarly to FIG. 7, the power transmission device 1 and the power relay device 40 installed on both surfaces of the partition wall 3, and the power reception device 2 a (including the load) disposed away from the partition wall 3 are included. Further, a second partition 3b exists on the opposite side of the partition 3 across the power receiving device 2a, and a second power relay device 40a is disposed on the surface of the second partition 3b so as to face the power receiving device 2a. ing. The second power relay device 40a has the same configuration as the power relay device 40. This non-contact power transmission system has substantially the same function as that shown in FIG. 5A and can provide the same effect. However, the effect of power relay can be further improved.

  Note that the non-contact power transmission system described in the above embodiment is configured so that the above functions work properly even when the partition wall is used, and even when the partition wall is mainly unsightly. Therefore, it is desirable that the communication function has a mechanism that allows the system administrator to update the firmware according to the usage environment. It is desirable to provide a mechanism that can be easily replaced when the life of the battery or capacitor is detected by the communication unit while taking measures against water leakage, dust, and electromagnetic leakage.

  According to the non-contact power transmission system of the present invention, a high-efficiency non-contact using the resonance state of the coil can be used at a sufficient speed in response to load fluctuations and abnormalities by using a power receiving device equipped with a battery. Power transmission can be performed stably at all times, and is useful for surveillance cameras and the like in which large-capacity information communication and wireless power transmission are integrated.

1, 1a Power transmission device 2, 2a Power reception device 3, 3a, 3b Bulkhead 4, 41b Power transmission unit 5 Power transmission communication unit 6, 9, 43 Battery 7, 41a Power reception unit 8 Power reception communication unit 10 Load 11 Power transmission coil 12, 12a Power transmission circuit 13 External power supply 14 Power factor improvement circuit 15, 16, 24, 25, 30 DD converter 17 Inverter 18 Low pass filter 19 Driver 20, 28, 33 Control unit 21 Power receiving coil 22, 22a Power receiving circuit 23 Rectifier 26, 31 Protection circuit 27, 32 Charging circuit 29, 34 Memory 40, 40a Power relay device 41 Power transmission / reception unit 41a Relay power reception unit 41b Relay power transmission unit 42 Relay communication unit

Claims (11)

A power transmission device having a power transmission coil and a power transmission communication unit each including a power transmission coil and a power transmission circuit to which a capacitor corresponding to a resonance capacitor is added; and
A power receiving coil having a power receiving coil to which a capacitor corresponding to a resonance capacity is added, a power receiving unit including a power receiving circuit, and a power receiving communication unit;
The power transmission coil and the power reception coil transmit power from the power transmission device to the power reception device via the partition wall by the action between the power transmission coil and the power reception coil to supply power to an external load. In a non-contact power transmission system configured to control the power transmission based on information by communication between,
The power receiving device includes a first power storage unit made of a battery or a capacitor, and the power of the first power storage unit is charged by charging the first power storage unit to a predetermined range with the power transmitted from the power transmission device. Control to enable supply to the external load, command the execution or stop of the power transmission to the power transmission device accompanying the control by the communication ,
When the external load to which power is supplied from the power receiving device changes from power OFF to ON, the power at the time of starting the power is supplied from the first power storage unit, and then the power transmitting device instructed by the communication A non-contact power transmission system for supplying power from power transmission to the external load .   2. The non-contact power according to claim 1, wherein when the power transmission from the power transmission device is stopped based on the communication from the power reception device, the non-contact power is controlled so as to accumulate the transmission power until the power transmission is stopped in the first power storage unit. Transmission system.   The non-contact power transmission system according to claim 1, wherein the power receiving device controls a charge / discharge state of the first power storage unit within a range of a charging rate of 20 to 90%.   The power transmission device has a function of detecting the presence or absence of the power receiving device, and has a function of stopping power transmission and outputting a notification signal when loss of the power receiving device is detected. The contactless power transmission system described in 1.   The power receiving device stores information on the number of times of charging and temperature as information on the charge / discharge state of the first power storage unit, compares the information with a list stored in advance in the power receiving device, and defines the list. The contactless power transmission system according to claim 1, which has a function of outputting a notification signal when it is out of the range. The power transmission communication unit outputs the notification signal by an electric signal, sound, or light from a device provided in the power transmission device, and to a user by a device other than the power transmission device through communication with another communication device. The non-contact electric power transmission system according to claim 4 or 5 having a function of making a notification. A power relay device including a relay power reception unit having a function corresponding to the power reception unit, and a relay power transmission unit having a function corresponding to the power transmission unit;
The contactless power transmission system according to claim 1, wherein the power transmitted from the power transmission device is received by the relay power reception unit in a contactless manner, and the received power is transmitted to the power reception device in a contactless manner by the relay power transmission unit. The power transmission device includes a second power storage unit including a battery or a capacitor,
The contactless power transmission system according to claim 1, wherein at least part of the power generated by the power transmission circuit can be stored in the second power storage unit. The non-contact power transmission system according to claim 8 , wherein the power transmission device controls a charge / discharge state of the second power storage unit within a range of a charging rate of 20 to 90%. The contactless power transmission system according to claim 8 , wherein power can be supplied from the second power storage unit to the power receiving device, and the power supply is controlled by the communication. When power transmission from the power transmission device is stopped based on the communication from the power reception device, power remaining in the power transmission circuit until power supply from an external power source to the power transmission device is stopped is stored in the second power storage. The non-contact power transmission system according to claim 8 , wherein the non-contact power transmission system is controlled so as to be stored in the unit.

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