JP2015119577A - Wireless power transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-power wireless power transmission system capable of ensuring stable operation of the electric apparatus while suppressing electromagnetic noises in particular for transmitting the power to the apparatus including a heat generator and an electric apparatus in a non-contact manner.SOLUTION: The wireless power transmission system includes: a heat generation unit that generates heat with a high electric power; and an electric apparatus that operates with a low electric power. The transmission system includes: a high power transmission unit for transmitting a high electric power; a low electric power transmission unit for transmitting a low electric power. A reception unit includes: a heat generation unit that receives the high electric power; and a low electric power reception unit that receives the low electric power, in which the low electric power reception unit supplies the electric power to the electric apparatus.

Description

  The present invention relates to a contactless power transmission device that performs power transmission between a power transmission device and a power reception device in a contactless (wireless) manner, 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. The non-contact electric power transmission apparatus for the receiving coil which comprises is for performing electric power transmission stably using the resonance state of a coil.

  As a method for transmitting power without contact (hereinafter referred to as wireless power feeding), an electromagnetic induction method using electromagnetic induction, a resonance power feeding method using resonance of an electric field or a magnetic field, and a microwave power transmission method using a microwave are known. ing. Among them, the electromagnetic induction method has already been put into practical use. This can be technically positioned as a mutual induction, and various studies have been made heretofore. There is an advantage that it can be configured with an inexpensive circuit, but there is a problem that the transmission distance is short. Therefore, recently, a resonance power feeding method that transmits power up to several meters using the resonance of the power transmission coil and the power reception coil has been proposed, and product development using this technology is being promoted mainly by electrical manufacturers and automobile manufacturers. .

  By the way, when increasing the power of the power feeding in the resonance power feeding method, it is important to design so as not to leak electromagnetic noise around. For example, the problem of electromagnetic noise can be reduced if electric power can be transmitted only to a necessary location by controlling the directivity of electric power transmission. However, since the frequency used for wireless power feeding is usually a microwave frequency or less, directivity is poor and it is difficult to suppress electromagnetic noise. In addition, when the power transmission coil and the power reception coil are displaced from the directly facing position for some reason, the generation of electromagnetic noise tends to be further increased.

  For this reason, in the case of non-contact power transmission, when increasing the power of the power supply, it is necessary to provide an electromagnetic wave shield or the like to prevent leakage of electromagnetic noise.

  In addition, when the environmental temperature changes or when a metal foreign object approaches the power transmitting device and the power receiving device, there is a problem that the frequency suitable for wireless power feeding causes a large transition. Therefore, in order to perform appropriate power transmission regardless of the external environment, it is necessary to provide a power transmission frequency adjustment mechanism and perform appropriate control on the power transmission coil and power reception coil that are responsible for power transmission. Although rare, if the coil suddenly drops during non-contact power transmission, a very high voltage may be generated in the coil, and in the worst case, the non-contact power transmission device may be broken. In order to prevent this, it is necessary to operate the transmission frequency adjusting mechanism appropriately and quickly.

  By the way, it is well known that there is a mobile flush toilet as disclosed in Patent Document 1. Install plumbing pipes with pipe connections on the walls and floors of multiple living rooms in the house, move the flush toilet and connect the plumbing indoor piping to the pipe connections installed on the walls and floor Thus, the use of a flush toilet becomes possible. The need for this mobile flush toilet is increasing with the aging society, such as when it is difficult for residents to go to the toilet by themselves.

  Further, as disclosed in Patent Document 2, a heated toilet seat device equipped with a heatable toilet seat portion and electric devices such as a motor, a solenoid valve, and various sensors is well known. The toilet seat is provided with an induction heating coil and a conductor (heat generating portion), and the conductor generates heat due to an eddy current induced by a magnetic field generated from the induction heating coil.

  When supplying electric power to a mobile flush toilet equipped with a heated toilet seat that has the characteristics of Patent Document 1 and Patent Document 2 described above, a resonance power feeding method capable of transmitting a large amount of power over a long distance is advantageous. For example, if a power transmission coil is installed near a wall or floor provided with water supply / drainage equipment piping and a power reception coil is provided in a mobile flush toilet, power can be supplied cordlessly to the flush toilet. In the case of the resonance power feeding method, other non-contact power transmission methods can transmit power with high efficiency even when the power transmission coil and the power receiving coil are slightly shifted, and also can transmit large power that can be fed to the battery of an automobile. Is superior to.

JP 2006-336665 A JP2013-146482A

  When power is supplied to a mobile flush toilet equipped with a heated toilet seat using a resonance power feeding device, a large amount of power is applied to the induction heating coil so that the conductor (heating unit) provided on the toilet seat generates sufficient heat. There is a need. On the other hand, electric devices such as motors, solenoid valves, and various sensors mounted on mobile flush toilets can operate with low power, but as a result of applying large power to the induction heating coil, large electromagnetic noise is generated, It turns out that it causes the equipment to malfunction.

  That is, the electric power given to the induction heating coil is used only for the purpose of generating eddy currents in the conductor, and the conductor only needs to generate heat. Noise is not a problem. On the other hand, electric devices such as motors, electromagnetic valves, and various sensors need to be protected from electromagnetic noise and to provide high-quality electric power in order to ensure accurate operation.

  Furthermore, when the environmental temperature changes, or when a metal foreign object approaches the power transmission device and the power reception device, when the power transmission conditions are out of the predetermined range, it is appropriate for the power transmission / reception coil responsible for power transmission. There was a need to control.

  A non-contact power transmission apparatus according to the present invention includes a power transmission device having a power transmission resonator configured by a power transmission coil and a resonance capacitor, and a power reception device having a power reception resonator configured by a power reception coil and a resonance capacitor, the power transmission device In the non-contact power transmission device that transmits power from the power receiving device to the power receiving device, the power transmission device includes a large power transmission unit for transmitting large power and a small power transmission unit for transmitting small power, The power transmission unit includes a high power transmission resonator including a high power transmission coil and a high power resonance capacity, and the small power transmission unit includes a small power transmission resonance including a small power transmission coil and a small power resonance capacity. The power receiving device includes a high power receiving unit for receiving the high power and a low power receiving unit for receiving the low power, the high power receiving unit including a high power receiving coil Beauty with large power receiving resonator constituted by high power resonant capacitor, the small power receiving unit is characterized in that it comprises a low-power receiving resonator constituted by small power receiving coil and the low power resonant capacitor.

  According to the non-contact power transmission apparatus of the present invention, high power and low power can be separated and transmitted. High power is supplied to, for example, a heat generating unit that generates heat, and low power is supplied to, for example, an electric device that requires high-quality power. As a result, it is possible to efficiently suppress the diffusion of electromagnetic noise to the electrical equipment despite the transmission of large power, and a stable and highly efficient contactless power transmission device can be realized.

The figure which showed the non-contact electric power transmission apparatus of this invention typically The figure which showed the structure of the power receiving apparatus of this invention provided with the heat generating part, the temperature detection part, and the electromagnetic wave shield The figure which showed the structure of the power receiving apparatus of this invention which added the electric power collection coil further to FIG. 2A The figure which showed the structure of the power receiving apparatus of this invention which added the thermoelectric element further to FIG. 2A The figure which showed the structure of the power receiving apparatus of this invention which added the battery further to FIG. 2A Flowchart at the time of initial operation in the non-contact power transmission apparatus of the present invention Flowchart during normal operation in the non-contact power transmission apparatus of the present invention

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

  In the present invention, wireless power transmission is performed using two paths. One is a path for high-power wireless power transmission, and the other is a path for low-power wireless power transmission. The wireless power transmission of the two paths may be performed at different frequencies or the same frequency. When the same frequency is used, it is necessary to devise a structure using an electromagnetic wave shield or the like so that excess power in the high power path is not transmitted to the low power path. As an example of providing a high-power path and a low-power path, there is a case where power is supplied in a non-contact manner to a mobile flush toilet equipped with a heated toilet seat.

  There are main differences between the two routes in the external load to be received. The high power path supplies power to a heat source regardless of the quality of the power, for example. In a mobile flush toilet equipped with a heated toilet seat, a large amount of electric power is applied to a large power transmission coil, and the electric power is used only for the purpose of generating eddy currents in a heating element. Since the heating element only needs to generate heat, a circuit such as a rectifier or voltage converter is not necessarily required for the path for high power. However, in order to receive large power more efficiently, the heating element is arranged as close as possible to the power transmission device than other components.

  On the other hand, the low-power path supplies power to electrical equipment that requires high-quality power with less noise. In a mobile flush toilet equipped with a heated toilet seat, small electric power is supplied to electrical devices such as motors, solenoid valves, and various sensors. A circuit to convert to is required.

  In addition, it is preferable that the power receiving device is provided with a temperature measuring device so that the temperature of the large power path, particularly the heating element can be measured. When the temperature of the heating element is equal to or higher than a predetermined temperature, power is transmitted from the power receiving side communication unit disposed in the power receiving device to the power transmitting side communication unit disposed in the power transmitting device, and is transmitted from the power transmitting device to the power receiving device. Adjust the transmission volume.

  It is also possible to incorporate a battery in the power receiving apparatus and supply power for communication from the battery when the non-contact power transmission apparatus is activated.

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

  The non-contact power transmission apparatus of the present invention is schematically shown in a perspective view in FIG. The non-contact power transmission device includes a power transmission device 100 and a power reception device 300. The power transmission device 100 and the power reception device 300 are installed to face both surfaces of the partition wall 600 and perform power transmission with the partition wall 600 interposed therebetween. For example, assuming that power is transmitted to a mobile flush toilet equipped with a heated toilet seat in a non-contact manner, the side wall of the flush toilet corresponds to the partition wall 600 when the power receiving device 300 is provided inside the flush toilet. . When the power transmission device 100 is installed on the outdoor side of the wall provided with the water supply / drainage equipment piping or on the lower side of the floor, the wall or floor corresponds to the partition wall 600. Alternatively, the partition wall 600 corresponds to a side wall of a flush toilet and may correspond to a wall or a floor. Hereinafter, in order to simplify and generalize the description, a case where power is transmitted across the partition wall 600 including any concept will be described.

  The power transmission device 100 includes a low power transmission unit, a high power transmission unit, and a power transmission side communication unit. The low power transmission unit includes a low power transmission coil 101 for transmitting low power and a low power transmission circuit 102 including a low power resonance capacitor. The high power transmission unit includes a high power transmission coil 201 for transmitting high power and a high power transmission circuit 202 including a resonance capacitor for high power. The power transmission side communication unit 103 is used for information communication with the power receiving apparatus 300.

  The power receiving device 300 includes a low-power power receiving unit, a heat generating unit, and a power receiving side communication unit. The low power receiving unit includes a low power receiving coil 301 for receiving low power and a power receiving circuit 302 for rectifying and converting to an appropriate voltage level. The power receiving circuit 302 also includes a low-power resonance capacitor. The power receiving side communication unit 303 is used for information communication with the power transmission device 100. The electric power output from the power receiving circuit 302 is supplied to electric devices such as sensors. For example, assuming a case where electric power is transmitted in a non-contact manner to a mobile flush toilet equipped with a heated toilet seat, electric devices include motors, solenoid valves, and various sensors. On the other hand, the power output from the high power power transmission coil 201 of the power transmission apparatus 100 is absorbed by the heat generating portion 401 and becomes heat by generating an eddy current.

  The present invention is characterized in that wireless power transmission is performed using two paths. One is a path for high-power wireless power transmission, and the other is a path for low-power wireless power transmission. That is, there is a feature in that there is a mechanism for transmitting two powers having different amounts of power from the power transmission device, and a mechanism for converting one power into a high-quality power in the power receiving device and using the other as a heat source. By performing wireless power transmission using the two routes, the circuit configuration can be changed as appropriate according to the amount of power to be transmitted, and the components used in the route can be selected as appropriate for the amount of power. Also, if the power transmission frequency is different for each path, mutual interference between paths can be reduced.

  The power receiving device has the following configuration when performing power conversion as described above and when supplying power as heat to the heat generating unit.

  2A to 2D show variations of the configuration diagram of the power receiving device 300 according to the present invention.

  FIG. 2A shows a power receiving device 300A that is the basis of the variations of FIGS. 2A to 2D. The heat generating part 401 is preferably made of a magnetic material that easily generates eddy current loss. In particular, it is preferable to use a material having a large complex component of permeability near the power transmission frequency of the power output from the high power power transmission circuit 202 of the power transmission device 100. This is because the size of the complex component of permeability is approximately proportional to the eddy current loss.

  A heat medium 402 is disposed around the heat generating portion 401. As the heat medium 402, for example, water is preferably used. The water heated by the heat medium 402 can be used as hot water for a flush toilet.

  In order to prevent the electromagnetic wave that has not been absorbed by the heat generating part 401 from diffusing to the surroundings, the electromagnetic wave shield 500 is disposed at least partly around the heat generating part 401 and the heat medium 402.

  The heat generating unit 401 is disposed closer to the power transmission device 100 than the other components in the power reception device 300 so as to efficiently receive power and prevent electromagnetic noise from being generated outside.

  The temperature detection unit 501 detects the temperature of the heat generating unit 401 and the temperature of the heat medium 402 and transmits the detected temperature to the power receiving side communication unit 303. As the temperature detection unit 501, for example, a thermistor is preferably used. When the detected temperature becomes higher than a predetermined set temperature, the power receiving side communication unit 303 transmits a command to the power transmission side communication unit 103 of the power transmission apparatus 100 to reduce the amount of power to be transmitted or to stop power transmission. . The power transmission side communication unit 103 transmits the received command to the high power power transmission circuit 202, and the high power power transmission circuit 202 reduces the amount of power transmitted or stops power transmission. Alternatively, when the detected temperature is transmitted from the power receiving side communication unit 303 of the power receiving device 300 to the power transmitting side communication unit 103 of the power transmitting device 100 and the detected temperature becomes higher than a predetermined set temperature, the power transmitting side communication unit 103 is used for high power. You may transmit the instruction | command which reduces the electric energy transmitted to the power transmission circuit 202, or stops power transmission.

  As communication means for realizing the power transmission side communication unit 103 and the power reception side communication unit 303, for example, ZigBee (registered trademark) or Bluetooth (registered trademark) can be used, or a low-power radio station or weak radio is used. It may be used. Even if the power transmission side communication unit 103 and the power reception side communication unit 303 are not provided, for example, it is possible to perform communication by providing a low power power transmission unit with a load communication control function.

  Below, the variation of the receiver 300 based on FIG. 2A is explained in full detail.

  FIG. 2B shows a receiving device 300B in which a power recovery coil 502 is added to the configuration of FIG. 2A. The power recovery coil 502 has a function of recovering again the electromagnetic waves that have not been absorbed by the heat generating portion 401 as electric power. The power received by the power recovery coil 502 is appropriately rectified and voltage-converted by the power receiving circuit 302, and then supplied from the power receiving circuit 302 to electrical devices such as the power receiving communication unit 303 and sensors.

  On the other hand, in FIG. 2B, it is also possible to arrange the power recovery coil 502 as an auxiliary coil without actively recovering the power from the power recovery coil 502. When the power recovery coil 502 is arranged as an auxiliary coil, a power receiving space with a uniform magnetic field can be formed between the high power power transmission coil 201 and the auxiliary coil, so that the heat generation efficiency of the heating element can be further improved. The details of the auxiliary coil are described in JP2013-85436A.

  FIG. 2C shows a receiving apparatus 300C in which a thermoelectric element 503 is added to the configuration of FIG. 2A. Electric power is generated by a temperature difference between the heat generating unit 401 that is high temperature and the heat medium 402 that is low in temperature compared to the heat generating unit 401, and the electric power is supplied to the power receiving circuit 302 of the power receiving device 300C. The electric power is appropriately rectified and voltage-converted by the power receiving circuit 302 and then supplied from the power receiving circuit 302 to an electric device such as a power receiving side communication unit 303 and sensors.

  FIG. 2D shows a receiving device 300D in which a battery 504 is added to the configuration of FIG. 2A. The battery 504 supplies power to the power receiving communication unit 303 when, for example, power is not transmitted from the power transmitting device 100 to the power receiving device 300 during the initial operation. That is, the battery 504 causes the state of the power receiving device 300 to act as a power source for transmitting information to the power transmission side communication unit 103 of the power transmission device 100.

  2A to 2D, specific examples of the electrical equipment include a motor, a solenoid valve, various sensors, etc., assuming that power is transmitted to a mobile flush toilet equipped with a heated toilet seat without contact. Can be mentioned.

  FIG. 3A shows a flowchart during initial operation of the non-contact power transmission apparatus of the present invention, and FIG. 3B shows a flowchart during normal operation. In the initial operation, two modes are prepared: a device confirmation mode when the power is turned on, and a device alarm mode that informs the user of an error in the device activation operation when an abnormality is detected at that time. During normal operation, the power sent from the power transmitting apparatus 100 to the power receiving apparatus 300 is appropriately controlled by applying PID control while monitoring the temperatures of the heat generating unit 401 and the heat medium 402. In order to save power, a standby mode for temporarily turning off the power is prepared, and control is performed to maintain a temperature set separately by the user.

  In the above description, the power output from the high-power power transmission coil 201 of the power transmission device 100 is directly absorbed by the heat generating unit 401 as an example. However, the power reception device 300 is provided with a high power power reception unit. The high power receiving unit may receive power from the high power receiving unit, and then the high power receiving unit may supply power to the heat generating unit 401.

  The non-contact power transmission device of the present invention transmits large power regardless of quality and small power of high quality separately, so that it is possible to greatly simplify the situation where the circuit configuration increases with increasing power normally. . In addition, it is possible to effectively prevent electromagnetic noise generated by high power from leaking into low power or leaking outside the apparatus, and is suitable for non-contact power transmission that requires stable operation.

DESCRIPTION OF SYMBOLS 100 Power transmission apparatus 101 Low power power transmission coil 102 Low power power transmission circuit 103 Power transmission side communication unit 201 High power power transmission coil 202 High power power transmission circuit 300 Power receiving apparatus 300A Power receiving apparatus A
300B Power receiving device B
300C Power receiving device C
300D Power receiving device D
301 Power receiving coil for low power 302 Power receiving circuit for low power 303 Power receiving side communication unit 401 Heat generating unit 500 Electromagnetic wave shield 501 Temperature detecting unit 502 Power recovery coil 503 Thermoelectric element 504 Battery 600 Bulkhead

Claims (10)

A power transmission device having a power transmission resonator composed of a power transmission coil and a resonance capacitor, and a power reception device having a power reception resonator composed of a power reception coil and a resonance capacitor, and transmitting power from the power transmission device to the power reception device In the contact power transmission device,
The power transmission device includes a high power transmission unit for transmitting large power and a low power transmission unit for transmitting small power,
The high power transmission unit includes a high power transmission resonator including a high power transmission coil and a high power resonance capacitor, and the low power transmission unit includes a small power including a small power transmission coil and a small power resonance capacitor. With power transmission resonator
The power receiving device includes a high power power receiving unit for receiving the high power and a low power power receiving unit for receiving the low power,
The high-power receiving unit includes a high-power receiving resonator configured by a high-power receiving coil and a high-power resonant capacitor, and the low-power receiving unit is configured by a small-power receiving coil and a small-power resonant capacitor. A non-contact power transmission device comprising a power receiving resonator.   The resonance frequency is different between the high power system composed of the high power transmission resonator and the high power reception resonator and the low power system composed of the small power transmission resonator and the small power reception resonator. The contactless power transmission device according to claim 1, wherein The non-contact power transmission device includes a heat generating part and an electric device,
The non-contact power transmission apparatus according to claim 1, wherein the large power receiving unit is a heat generating unit, and the small power receiving unit supplies the small power to the electric device.   The non-contact power transmission according to claim 3, wherein an electromagnetic wave shield is provided on at least a part of an outer periphery of the heat generating part so that electromagnetic noise generated from the heat generating part does not leak to the electric device. apparatus. The power transmission device includes a power transmission side communication unit,
The power receiving device includes a power receiving side communication unit and a temperature detection unit,
A heat medium is arranged around the heat generating part,
The temperature detection unit detects the temperature of the heating unit or the heat medium,
When the detected temperature becomes higher than a predetermined set temperature, the power receiving side communication unit transmits a command to adjust the amount of power to be transmitted to the power transmission side communication unit of the power transmission device,
The power transmission side communication unit transmits the received command to the high power power transmission circuit,
The non-contact power transmission device according to claim 4, wherein the high-power transmission circuit adjusts an amount of power transmitted based on the command. The power transmission device includes a power transmission side communication unit,
The power receiving device includes a power receiving side communication unit and a temperature detection unit,
A heat medium is arranged around the heat generating part,
The temperature detection unit detects the temperature of the heating unit or the heat medium,
The power reception side communication unit transmits the detected temperature to a power transmission side communication unit of the power transmission device,
When the detected temperature received is higher than a preset temperature, the power transmission side communication unit transmits a command to adjust the amount of power transmitted to the high power power transmission circuit,
The non-contact power transmission device according to claim 4, wherein the high-power transmission circuit adjusts an amount of power transmitted based on the command.   A power recovery coil is disposed on the opposite side of the heat generating unit to the power transmission device, the power recovery coil converts electromagnetic waves that are not absorbed by the heat generating unit into recovered power, and the recovered power is transmitted to the power receiving side communication unit or The contactless power transmission device according to claim 5, wherein the contactless power transmission device is supplied to at least one of the electrical devices.   The auxiliary coil is disposed on the opposite side of the heat generating portion from the power transmission device, and the heat generating portion is disposed in a power receiving space formed between the high power power transmitting coil and the auxiliary coil. The contactless power transmission device according to 5 or 6.   A thermoelectric element is disposed in the vicinity of the heat generating part, the thermoelectric element generates power due to a temperature difference between the heat generating part and the heat medium, and the electric power obtained by the power generation is at least in the power receiving side communication part or the electric device. The non-contact power transmission device according to claim 5 or 6, wherein the non-contact power transmission device is supplied to one side.   The contactless power transmission device according to claim 5, wherein a battery is disposed in the power receiving device, and the battery supplies power to the power receiving side communication unit.

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