JP2014054134A - Power transmission device for non-contact power transmission system, non-contact power transmission system, and power transmission capability adjusting method for non-contact power transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission device for a non-contact power transmission system, a non-contact power transmission system and a power transmission capability adjusting method for the non-contact power transmission system that can increase the power supply capability and reduce the power loss.SOLUTION: A power transmission device 10 for a non-contact power transmission system 1 has a driving unit 40 for driving an output unit 30 and a driving system switching unit 50. The driving system switching unit 50 selects any one of a half-bridge driving system or a full-bridge driving system as a driving system of the driving unit 40 in accordance with power consumption information of a power receiving device 20.

Description

  The present invention relates to a power transmission device of a non-contact power transmission system, a non-contact power transmission system, and a method for adjusting the power transmission capability of the non-contact power transmission system.

  A conventional non-contact power transmission system includes a power transmission device and a power reception device. The power receiving device transmits the output voltage information to the power transmitting device. The power transmission device controls the output voltage based on the output voltage information of the power receiving device. Note that Patent Document 1 discloses an example of a conventional non-contact power transmission system.

JP 2012-5185 A

  A power transmission device of a non-contact power transmission system that transmits power to a plurality of types of power receiving devices having different power consumptions has a configuration capable of supplying the power receiving device with power that is greater than or equal to the maximum power consumption of the plurality of types of power receiving devices. . In the configuration of the power transmission device that can supply a large amount of power, power loss increases according to the power supply capability. For this reason, a power transmission device using a configuration that realizes a small power loss is limited in power supply capability. For this reason, the types of power receiving devices that can be applied to the non-contact power transmission system are limited.

  The present invention was created based on the above background, and has a large power supply capability and low power loss. A power transmission device, a non-contact power transmission system, and a non-contact power transmission system for a non-contact power transmission system. An object of the present invention is to provide a power transmission capacity adjustment method.

  (1) The first means is “a power transmission device of a non-contact power transmission system, wherein the power transmission device includes an output unit, an oscillation unit, a drive unit, and a drive system switching unit, and the output unit includes: Power is transmitted based on a signal output from the driving unit, the oscillation unit outputs a clock signal to the driving unit, and the driving unit has a first driving method or a second driving having different power transmission capabilities. The output unit is driven by a method, and the drive method switching unit includes a power transmission device of a non-contact power transmission system that selects the first drive method or the second drive method according to power consumption information of a power receiving device. .

  (2) The second means is that “the power transmission device has at least one of an output unit driving voltage that is a voltage input to the driving unit, a frequency of the clock signal, and a time ratio of the clock signal. It includes a power transmission device of a non-contact power transmission system that adjusts the power transmission capability of the first driving method and the power transmission capability of the second driving method by changing.

  (3) The third means is that “the drive unit has a half-bridge drive method as the first drive method and a full-bridge drive method as the second drive method”. including.

  (4) The fourth means is that “the driving unit has a plurality of transistors for driving the output unit, and the driving method switching unit outputs a clock signal to the plurality of transistors, thereby A power transmission device of a non-contact power transmission system that selects the first driving method or the second driving method.

(5) The fifth means includes “a non-contact power transmission system including the power transmission device and the power reception device”.
(6) The sixth means is “a power transmission capability adjustment method of a contactless power transmission system, wherein the contactless power transmission system includes a power transmission device and a power reception device, and the power transmission device includes a power transmission capability. Have a first driving method and a second driving method different from each other, and the power transmission capacity adjustment method includes a step of detecting a power consumption of the power receiving device in the power receiving device, and a detection result of the power consumption A non-contact power transmission system including a step of transmitting from a power reception device to the power transmission device, and a step of selecting one of the first drive method and the second drive method based on a detection result of the power consumption. "Power transmission capacity adjustment method".

  (7) The seventh means is that “the power transmission capacity adjustment method is an output unit drive voltage of the power transmission device, a frequency of the output unit drive clock signal, and a time ratio of the output unit drive clock signal. A method of adjusting a power transmission capability of a non-contact power transmission system including a step of changing at least one of the above.

  The power transmission device of the non-contact power transmission system, the non-contact power transmission system, and the power transmission capacity adjustment method of the non-contact power transmission system contribute to the expansion of power supply capacity and the reduction of power loss.

The block diagram of the non-contact electric power transmission system in 1st Embodiment. The circuit block diagram of the power transmission part in 1st Embodiment. The operation | movement waveform diagram of the power transmission apparatus in 1st Embodiment. The power transmission capability control flowchart of the power transmission apparatus in 1st Embodiment. The block diagram of the non-contact electric power transmission system in 2nd Embodiment. The electric power transmission capability adjustment flow figure of the power transmission apparatus in 2nd Embodiment. The circuit block diagram of the drive system switching part in other embodiment. The operation | movement waveform diagram of the power transmission apparatus in other embodiment.

(First embodiment)
With reference to FIG. 1, the structure of the non-contact electric power transmission system 1 is demonstrated.
The non-contact power transmission system 1 includes a power transmission device 10 and a power reception device 20. The power transmission device 10 includes a DC voltage generation unit 11, an oscillation unit 12, a drive method switching unit 50, a drive unit 40, an output unit 30, and a power transmission side detection unit 15.

  The DC voltage generator 11 generates a DC voltage from the commercial power source 2. The DC voltage generator 11 supplies the generated voltage to the power transmission side high potential power line 17 and the power transmission side low potential power line 18. The drive unit 40 is connected between the power transmission side high potential power line 17 and the power transmission side low potential power line 18.

With reference to FIG. 2, the circuit configuration of the drive unit 40 will be described.
The drive unit 40 includes a P-type first transistor T1, a P-type second transistor T2, an N-type third transistor T3, and an N-type fourth transistor T4. The drive unit 40 includes a first diode D1 and a first capacitor C1 associated with the first transistor T1. The drive unit 40 includes a second diode D2 and a second capacitor C2 associated with the second transistor T2. The drive unit 40 includes a third diode D3 and a third capacitor C3 associated with the third transistor T3. The drive unit 40 includes a fourth diode D4 and a fourth capacitor C4 associated with the fourth transistor T4. In the drive unit 40, the transistors T1 to T4 are driven by the drive signal Φp1, the drive signal Φp2, the drive signal Φn1, and the drive signal Φn2. The drive unit 40 switches the direction of the current flowing through the power transmission side resonance capacitor 31 and the power transmission coil 32 configuring the output unit 30 based on the driving state of the transistors T1 to T4. The drive unit 40 supplies AC power to the power transmission coil 32. The power transmission coil 32 transmits power to the power reception coil 61 using an electromagnetic induction action.

  The driving method switching unit 50 outputs a driving signal Φp1 for driving the first transistor T1 to the driving unit 40. The driving method switching unit 50 outputs a driving signal Φp2 for driving the second transistor T2 to the driving unit 40. The drive method switching unit 50 outputs a drive signal Φn1 for driving the third transistor T3 to the drive unit 40. The drive method switching unit 50 outputs a drive signal Φn2 for driving the fourth transistor T4 to the drive unit 40.

  The drive system switching unit 50 sets the output levels of the drive signal Φp1, the drive signal Φp2, the drive signal Φn1, and the drive signal Φn2 to a high level or a low level according to the signal Φc and the signal SW. The drive system switching unit 50 sets an output level for each drive signal. The drive system switching unit 50 sets the potential of the power transmission side high potential power supply line 17 as the high level of the drive signal output. The drive system switching unit 50 sets the potential of the power transmission side low potential power supply line 18 as the low level of the drive signal output.

The operation of the drive unit 40 will be described below.
The drive unit 40 drives the transistors T <b> 1 to T <b> 4 according to the drive signal received from the drive method switching unit 50. The drive unit 40 changes the potential difference between the first end 30A and the second end 30B of the output unit 30 according to the driving state of the transistors T1 to T4.

  The first transistor T1 is turned on or off according to the drive signal Φp1. The first transistor T1 is turned on when the low-level drive signal Φp1 is input. The first transistor T1 is turned off when the high-level drive signal Φp1 is input.

  The second transistor T2 is turned on or off according to the drive signal Φp2. The second transistor T2 is turned on when the low-level drive signal Φp2 is input. The second transistor T2 is turned off when the high-level drive signal Φp2 is input.

  The third transistor T3 forms an on or off state according to the drive signal Φn1. The third transistor T3 is turned on when the high-level drive signal Φn1 is input. The third transistor T3 is turned off when the low-level drive signal Φn1 is input.

  The fourth transistor T4 is turned on or off according to the drive signal Φn2. The fourth transistor T4 is turned on when the high-level drive signal Φn2 is input. The fourth transistor T4 forms an off state when the low-level drive signal Φn2 is input.

  The oscillating unit 12 generates a drive signal Φp1, a drive signal Φn1, a drive signal Φp2, and a clock signal Φc that is the basis of the drive signal Φn2 applied to the drive unit 40. The oscillating unit 12 repeatedly outputs a high level signal Φc and a low level signal Φc at a predetermined frequency. The oscillation unit 12 sets the potential of the power transmission side high potential power supply line 17 as the high level of the clock signal Φc. The oscillation unit 12 sets the potential of the power transmission side low potential power supply line 18 as the low level of the clock signal Φc. The drive system switching unit 50 generates a drive signal Φp1, a drive signal Φn1, a drive signal Φp2, and a drive signal Φn2 to be given to the drive unit 40 based on the clock signal Φc. The power transmission side detection unit 15 compares the power consumption information in the power receiving device 20 received via the power transmission coil 32 with a predetermined threshold value. The power transmission side detection unit 15 outputs the comparison result to the drive method switching unit 50 as the switching signal SW. The power transmission side detection unit 15 sets the potential of the power transmission side high potential power supply line 17 as the high level of the switching signal SW. The power transmission side detection unit 15 sets the potential of the power transmission side low potential power supply line 18 as the low level of the switching signal SW. The drive method switching unit 50 controls the signal levels of the drive signal Φp1, the drive signal Φn1, the drive signal Φp2, and the drive signal Φn2 to be supplied to the drive unit 40 in accordance with the switch signal SW received from the power transmission side detection unit 15.

With reference to FIG. 2, a circuit configuration of the driving method switching unit 50 will be described.
The drive system switching unit 50 includes a first NAND gate 51, a first NOR gate 52, a first inverter 53, and a buffer 54.

  A first input part of the first NAND gate 51 is connected to the oscillation part 12. The second input unit of the first NAND gate 51 is connected to the power transmission side detection unit 15. The output part of the first NAND gate 51 is connected to the first transistor T1.

  The first input part of the first NOR gate 52 is connected to the output part of the first inverter 53. A second input unit of the first NOR gate 52 is connected to the oscillation unit 12. The output part of the first NOR gate 52 is connected to the third transistor T3.

  The input unit of the first inverter 53 is connected to the power transmission side detection unit 15. An input unit of the buffer 54 is connected to the oscillation unit 12. The output part of the buffer 54 is connected to the second transistor T2 and the fourth transistor T4.

  The gate terminal of the first transistor T1 is connected to the output part of the first NAND gate 51. The gate terminal of the second transistor T2 is connected to the output unit of the buffer 54. The gate terminal of the third transistor T3 is connected to the output part of the first NOR gate 52. The gate terminal of the fourth transistor T4 is connected to the output unit of the buffer 54.

  The power transmission side detection unit 15 outputs a high-level signal SW when the power consumption information in the power receiving device 20 is equal to or greater than a threshold value. The power transmission side detection unit 15 outputs a low-level signal SW when the power consumption information in the power receiving device 20 is less than the threshold value.

With reference to FIG. 3, the operation of the drive method switching unit 50 will be described.
The drive system switching unit 50 outputs a drive signal Φp1, a drive signal Φp2, a drive signal Φn1, and a drive signal Φn2 based on the signal Φc and the signal SW.

  The drive system switching unit 50 performs three logical operations. The drive system switching unit 50 performs a negative logic operation on the signal SW in the first inverter 53. In the first NAND gate 51, the driving method switching unit 50 performs a negative OR operation on the signal SW and the signal Φc. In the first NOR gate 52, the driving method switching unit 50 performs a NAND operation on the output signal of the first inverter 53 and the signal Φc.

  The driving method switching unit 50 generates a driving signal Φp1 based on the calculation result of the first NAND gate 51, and outputs the generated driving signal Φp1 to the first transistor T1. The drive method switching unit 50 generates a drive signal Φn1 based on the calculation result of the first NOR gate 52, and outputs the generated drive signal Φn1 to the third transistor T3. The drive system switching unit 50 generates a drive signal Φp2 based on the signal Φc via the buffer 54, and outputs the generated drive signal Φp2 to the second transistor T2. The drive method switching unit 50 generates a drive signal Φn2 based on the signal Φc via the buffer 54, and outputs the generated drive signal Φn2 to the fourth transistor T4.

  The first NAND gate 51 fixes the output level of the drive signal Φp1 to a high level when the signal SW is at a low level. That is, the first NAND gate 51 fixes the first transistor T1 in the off state when the signal SW is at a low level.

  The first NOR gate 52 fixes the output level of the drive signal Φn1 at a low level when the signal SW is at a low level. That is, the first NOR gate 52 fixes the third transistor T3 in the off state when the signal SW is at a low level.

With reference to FIG. 3, an example of operation | movement of the power transmission apparatus 10 is demonstrated.
The power transmission side detection unit 15 outputs a high-level signal SW to the drive method switching unit 50 as a result of comparing the power consumption information received from the power receiving device 20 with a predetermined threshold value at time t11.

  The driving method switching unit 50 operates as follows during the period of time t11 to t12. The drive method switching unit 50 receives the low level signal Φc from the oscillation unit 12 and receives the high level signal SW from the power transmission side detection unit 15. The drive method switching unit 50 performs a logical operation on the low level signal Φc and the high level signal SW, thereby causing the high level drive signal Φp1, the low level drive signal Φp2, the high level drive signal Φn1, and the low level drive signal Φn1. The drive signal Φn2 is output.

  The drive unit 40 operates as follows during the period of time t11 to t12. The first transistor T1 is turned off when the high-level drive signal Φp1 is input. The second transistor T2 is turned on when the low-level drive signal Φp2 is input. The third transistor T3 is turned on when the high-level drive signal Φn1 is input. The fourth transistor T4 is turned off when the low-level drive signal Φn2 is input.

  The output unit 30 operates as follows during the period from time t11 to t12. The first end 30A of the output unit 30 is connected to the power transmission side high potential power line 17 through the second transistor T2. The second end 30B of the output unit 30 is connected to the power transmission side low potential power line 18 via the third transistor T3.

  In the period from time t11 to t12, the power transmission device 10 has a potential of the power transmission side high potential power supply line 17 and a power transmission side low potential from the first end 30A of the output unit 30 toward the second end 30B of the output unit 30. A current corresponding to the difference from the potential of the power supply line 18 is supplied.

  The driving method switching unit 50 operates as follows during the period of time t12 to t13. The drive method switching unit 50 receives the high level signal Φc from the oscillation unit 12 and receives the high level signal SW from the power transmission side detection unit 15. The drive method switching unit 50 performs a logical operation on the high level signal Φc and the high level signal SW, thereby causing the low level drive signal Φp1, the high level drive signal Φp2, the low level drive signal Φn1, and the high level signal Φn1. The drive signal Φn2 is output.

  The drive unit 40 operates as follows during the period of time t12 to t13. The first transistor T1 is turned on when the low-level driving signal Φp1 is input. The second transistor T2 is turned off when the high-level drive signal Φp2 is input. The third transistor T3 is turned off when the low-level drive signal Φn1 is input. The fourth transistor T4 is turned on when the high-level drive signal Φn2 is input.

  The output unit 30 operates as follows during the period from time t12 to t13. The first end 30A of the output unit 30 is connected to the power transmission side low potential power line 18 via the fourth transistor T4. The second end 30B of the output unit 30 is connected to the power transmission side high potential power line 17 via the first transistor T1.

  In the period from time t12 to t13, the power transmission device 10 is configured such that the power transmission side high potential power line 17 and the power transmission side low potential are directed from the second end 30B of the output unit 30 toward the first end 30A of the output unit 30. A current corresponding to the difference from the potential of the power supply line 18 is supplied.

  The drive system switching unit 50, the drive unit 40, and the output unit 30 operate as follows during the period from time t13 to t14. The drive method switching unit 50, the drive unit 40, and the output unit 30 perform the same operation as the operation in the period from time t11 to t12 in the period from time t13 to t14.

  The drive system switching unit 50, the drive unit 40, and the output unit 30 operate as follows during the period of time t14 to t15. The driving method switching unit 50, the driving unit 40, and the output unit 30 perform the same operation as the operation in the period from time t12 to t13 in the period from time t14 to t15.

  The drive system switching unit 50, the drive unit 40, and the output unit 30 operate as follows during the period from time t15 to t1. The driving method switching unit 50, the driving unit 40, and the output unit 30 perform the same operation as the operation in the period from time t11 to t12 in the period from time t15 to t1.

  For this reason, the power transmission device 10 has the potential of the power transmission side high potential power supply line 17 and the potential of the power transmission side low potential power supply line 18 during the period of time t11 to t1 when the power transmission side detection unit 15 outputs the high level switching signal SW. A current corresponding to the difference is supplied to the output unit 30. The power transmission device 10 switches the direction of the current supplied to the output unit 30 according to the level of the clock signal Φc during the period from time t11 to t1 when the power transmission side detection unit 15 outputs the high level switching signal SW. That is, the drive unit 40 forms a full bridge circuit.

  The power transmission side detection unit 15 outputs a low-level signal SW to the drive method switching unit 50 as a result of comparing the power consumption information received from the power receiving device 20 with a predetermined threshold value at time t1.

  The driving method switching unit 50 operates as follows during the period of time t1 to t21. The drive system switching unit 50 receives the low level signal Φc from the oscillation unit 12 and receives the low level signal SW from the power transmission side detection unit 15. The drive system switching unit 50 performs a logical operation on the low level signal Φc and the low level signal SW, thereby causing the high level drive signal Φp1, the low level drive signal Φp2, the low level drive signal Φn1, and the low level drive signal Φn1. The drive signal Φn2 is output.

  The drive unit 40 operates as follows during the period from time t1 to time t21. The first transistor T1 is turned off when the high-level drive signal Φp1 is input. The second transistor T2 is turned on when the low-level drive signal Φp2 is input. The third transistor T3 is turned off when the low-level drive signal Φn1 is input. The fourth transistor T4 is turned off when the low-level drive signal Φn2 is input.

  The output unit 30 operates as follows during the period from time t1 to t21. The first end 30A of the output unit 30 is connected to the power transmission side high potential power line 17 through the second transistor T2. The second end 30B of the output unit 30 is connected to the power transmission side high potential power line 17 via the first capacitor C1. The second end 30B of the output unit 30 is connected to the power transmission side low potential power line 18 via the third capacitor C3.

  In the period from time t1 to t21, the power transmission device 10 is configured such that the potential of the power transmission-side high-potential power line 17 and the first capacitor from the first end 30A of the output unit 30 toward the second end 30B of the output unit 30 A current corresponding to the potential of the power transmission side high potential power supply line 17 and the potential of the power transmission side low potential power supply line 18 divided by C1 and the third capacitor C3 is supplied.

  The driving method switching unit 50 operates as follows during the period from time t21 to t22. The drive method switching unit 50 receives the high level signal Φc from the oscillation unit 12 and receives the low level signal SW from the power transmission side detection unit 15. The drive system switching unit 50 performs a logical operation on the high level signal Φc and the low level signal SW, thereby causing the high level drive signal Φp1, the high level drive signal Φp2, the low level drive signal Φn1, and the high level drive signal Φn1. The drive signal Φn2 is output.

  The drive unit 40 operates as follows during the period from time t21 to t22. The first transistor T1 is turned off when the high-level drive signal Φp1 is input. The second transistor T2 is turned off when the high-level drive signal Φp2 is input. The third transistor T3 is turned off when the low-level drive signal Φn1 is input. The fourth transistor T4 is turned on when the high-level drive signal Φn2 is input.

  The output unit 30 operates as follows during the period from time t21 to t22. The first end 30A of the output unit 30 is connected to the power transmission side low potential power line 18 via the fourth transistor T4. The second end 30B of the output unit 30 is connected to the power transmission side high potential power line 17 via the first capacitor C1. The second end 30B of the output unit 30 is connected to the power transmission side low potential power line 18 via the third capacitor C3.

  The power transmission device 10 was divided by the first capacitor C1 and the third capacitor C3 from the second end 30B of the output unit 30 toward the first end 30A of the output unit 30 during the period of time t21 to t22. A current corresponding to the potential of the power transmission side high potential power line 17 and the potential of the power transmission side low potential power line 18 and the potential of the power transmission side low potential power line 18 is supplied.

  The drive system switching unit 50, the drive unit 40, and the output unit 30 operate as follows during the period from time t22 to t23. The driving method switching unit 50, the driving unit 40, and the output unit 30 perform the same operation as the operation in the period from time t1 to t21 in the period from time t22 to t23.

  The drive system switching unit 50, the drive unit 40, and the output unit 30 operate as follows during the period from time t23 to t24. The driving method switching unit 50, the driving unit 40, and the output unit 30 perform the same operation as the operation in the period from time t21 to t22 in the period from time t23 to t24.

  For this reason, the power transmission device 10 includes the potential of the power transmission side high potential power line 17, the first capacitor C1, and the third capacitor during the period from time t1 to time t24 when the power transmission side detection unit 15 outputs the low level switching signal SW. A current corresponding to the potential of the power transmission side high potential power supply line 17 and the potential of the power transmission side low potential power supply line 18 divided by C3 is supplied to the output unit 30. The power transmission device 10 switches the direction of the current supplied to the output unit 30 according to the level of the clock signal Φc during the period from time t1 to t24 when the power transmission side detection unit 15 outputs the low level switching signal SW. That is, the drive unit 40 forms a half bridge circuit.

  The power receiving device 20 includes an input unit 60, a rectifier circuit 21, and a constant voltage circuit 22. The input unit 60 includes a power receiving coil 61 and a power receiving side resonance capacitor 62. The rectifier circuit 21 converts AC power received at the input unit into DC power. The constant voltage circuit 22 generates a predetermined voltage from the output of the rectifier circuit 21. The constant voltage circuit 22 supplies the generated voltage to the load 23 via the power receiving side high potential power line 27 and the power receiving side low potential power line 28. The power receiving side detection unit 26 detects the potential of the power receiving side high potential power supply line 27. The power receiving side detection unit 26 detects the current flowing from the power receiving side high potential power line 27 to the power receiving side low potential power line 28 via the load 23 using the voltage generated in the resistor 24. The power reception side control unit 25 generates a control signal for the constant voltage circuit 22 based on the detection result output of the power reception side detection unit 26. The constant voltage circuit 22 controls the output voltage based on the output of the power receiving side control unit 25.

  The power receiving side detection unit 26 supplies the detection result output to the power receiving coil 61. The detection result output of the power reception side detection unit 26 is transmitted to the power transmission coil 32 of the power transmission device 10 as power consumption information of the power reception device 20. The power receiving device 20 transmits power consumption information to the power transmitting device 10 using a load modulation method.

  The power transmission side detection unit 15 of the power transmission device 10 compares the power consumption information transmitted from the power reception device 20 to the power transmission coil 32 with a predetermined threshold value. The power transmission side detection unit 15 outputs the switching signal SW to the driving method switching unit 50 based on the comparison result between the power consumption information and the threshold value.

The power transmission capability control operation of the power transmission device 10 will be described with reference to FIG.
In step S <b> 11, the drive unit 40 selects the half-bridge drive method when the power transmission device 10 is turned on. As a result, the power transmission device 10 starts power transmission by the half-bridge driving method. When the power from the power transmitting device 10 is transmitted to the power receiving device 20, the power receiving side detection unit 26 detects the power consumption of the power receiving device 20 in step S12. In step S <b> 13, the power reception side detection unit 26 transmits the power consumption information of the power reception device 20 to the power transmission device 10. In step S14, the power transmission side detection unit 15 compares the power consumption information with a predetermined threshold value. When the power consumption information is smaller than the threshold value, the driving method switching unit 50 switches the driving method of the driving unit 40 to the half bridge driving method in step S15. When the power consumption information is larger than the threshold value, the driving method switching unit 50 switches the driving method of the driving unit 40 to the full bridge driving method in step S16. In step S <b> 17, the power transmission device 10 performs power transmission using the selected driving method. The non-contact power transmission system 1 repeats Steps S12 to S17 during a period in which power transmission from the power transmission device 10 to the power reception device 20 is continued.

The non-contact power transmission system 1 has the following effects.
(1) The power transmission device 10 of the non-contact power transmission system 1 includes a drive unit 40, a drive method switching unit 50, and a power transmission side detection unit 15. The power transmission side detection unit 15 compares the power consumption information transmitted from the power receiving device 20 with a predetermined threshold value. The drive method switching unit 50 selects the drive method of the drive unit 40 based on the comparison result of the power transmission side detection unit 15. According to this configuration, the power transmission device 10 selects the full bridge drive method as the drive method of the drive unit 40 when the power consumption in the power receiving device 20 is large. The power transmission device 10 selects the half-bridge driving method as the driving method of the driving unit 40 when the power consumption in the power receiving device 20 is small. For this reason, the non-contact power transmission system 1 having a large power supply capability and a small power loss can be realized.

  (2) The power receiving device 20 of the non-contact power transmission system 1 includes a constant voltage circuit 22, a resistor 24, and a power receiving side detection unit 26. The power receiving side detection unit 26 detects the current flowing through the load 23 using the voltage generated in the resistor 24. The power reception side detection unit 26 transmits the detection result to the power transmission device 10 as power consumption information of the power reception device 20. The power transmission side detection unit 15 outputs the switching signal SW based on the power consumption information transmitted from the power receiving device 20. The drive method switching unit 50 selects the drive method of the drive unit 40 based on the switching signal SW. According to this configuration, the drive unit 40 of the power transmission device 10 selects a drive method based on the power consumption information of the power reception device 20. For this reason, at the time of the power transmission from the power transmission apparatus 10, the drive system switching of the drive part 40 is performed in real time. For this reason, the drive unit 40 is supplied with power by an appropriate drive method according to the power consumption of the power receiving device 20.

  (3) The drive unit 40 includes transistors T1 to T4. The drive system switching unit 50 outputs drive signals Φp1, Φp2, Φn1, and Φn2 that drive the transistors T1 to T4. The driving method switching unit 50 controls the levels of the driving signals Φp1, Φp2, Φn1, and Φn2 according to the switching signal SW. According to this configuration, the drive system selection of the drive unit 40 can be realized with a simple circuit configuration.

(Second Embodiment)
With reference to FIG. 5, the non-contact electric power transmission system 1 of 2nd Embodiment is demonstrated.
The non-contact power transmission system 1 of the second embodiment has a different configuration in the following parts compared to the non-contact power transmission system 1 of the first embodiment, and has the same configuration in other parts. In addition, about the structure which is common in the non-contact electric power transmission system 1 of 1st Embodiment, the same code | symbol is attached | subjected and the part or all of the description is abbreviate | omitted.

  The non-contact power transmission system 1 according to the first embodiment includes a constant voltage circuit 22 in the power receiving device 20. On the other hand, the non-contact power transmission system 1 of the second embodiment includes a power transmission side control unit 16 in the power transmission device 10. The power transmission side control unit 16 outputs control signals for the DC voltage generation unit 11 and the oscillation unit 12 based on the potential information of the power reception side high potential power line 27 from the power reception device 20. The power transmission side control unit 16 outputs a switching signal SW for selecting the driving method of the driving unit 40 based on the power consumption information from the power receiving device 20.

The operation of the non-contact power transmission system 1 will be described.
The power receiving side detection unit 26 of the power receiving device 20 detects the potential of the power receiving side high potential power line 27. The power receiving side detection unit 26 detects the current flowing from the power receiving side high potential power line 27 to the power receiving side low potential power line 28 via the load 23 using the voltage generated in the resistor 24. The power receiving side detection unit 26 supplies the detection result output to the power receiving coil 61. The detection result output of the power reception side detection unit 26 is transmitted to the power transmission coil 32 of the power transmission device 10 as potential information of the power reception side high potential power supply line 27 and power consumption information of the power reception device 20. The power receiving device 20 transmits the potential information and power consumption information of the power receiving side high potential power supply line 27 to the power transmitting device 10 using the load modulation method.

  The power transmission side detection unit 15 of the power transmission device 10 detects the potential information of the power reception side high potential power line 27 transmitted from the power reception device 20 to the power transmission coil 32. The power transmission side detection unit 15 outputs the detection result of the potential information of the power reception side high potential power supply line 27 to the power transmission side control unit 16. The power transmission side detection unit 15 compares the power consumption information transmitted from the power receiving device 20 to the power transmission coil 32 with a predetermined threshold value. The power transmission side detection unit 15 outputs the comparison result between the power consumption information and the threshold value to the power transmission side control unit 16. The power transmission side control unit 16 outputs a control signal for controlling the generated voltage to the DC voltage generation unit 11 based on the detection result of the power transmission side detection unit 15. The power transmission side control unit 16 outputs a control signal for controlling the frequency and the time ratio of the clock signal Φc to the oscillation unit 12 based on the detection result of the power transmission side detection unit 15. The power transmission side control unit 16 outputs a switching signal SW to the drive method switching unit 50 based on the comparison result of the power transmission side detection unit 15.

  The drive unit 40 is a drive method selected based on the output of the power transmission side control unit 16, the frequency and time ratio of the clock signal Φc, and the power transmission side high potential power line 17 and the power transmission side low potential power source which are output unit drive voltages. Based on the voltage between the lines 18, the power transmission side resonance capacitor 31 and the power transmission coil 32 are driven.

With reference to FIG. 6, the content of the power transmission capacity adjustment control will be described.
The power transmission side control unit 16 executes power transmission capacity adjustment control. The basic configuration of the power transmission capacity adjustment control can be described by the flowchart of FIG.

  In step S21, the drive unit 40 selects the half-bridge drive method when the power transmission device is turned on. As a result, the power transmission device 10 starts power transmission by the half-bridge driving method. When the power from the power transmitting device 10 is transmitted to the power receiving device 20, the power transmission side control unit 16 sets the drive voltage of the output unit 30 so that the power receiving side high potential power line 27 becomes a predetermined potential in step S22. The output voltage of the DC voltage generator 11 and the frequency and duty ratio of the clock signal Φc of the oscillator 12 are controlled. In step S <b> 23, the power receiving side detection unit 26 detects the potential of the power receiving side high potential power line 27 and the power consumption of the power receiving device 20. In step S <b> 24, the power receiving side detection unit 26 transmits the potential information of the power receiving side high potential power supply line 27 and the power consumption information of the power receiving device 20 to the power transmitting device 10. In step S25, the power transmission side detection unit 15 compares the power consumption information with a predetermined threshold value. When the power consumption information is smaller than the threshold value, the driving method switching unit 50 switches the driving method of the driving unit 40 to the half bridge driving method in step S26. When the power consumption information is larger than the threshold value, the driving method switching unit 50 switches the driving method of the driving unit 40 to the full bridge driving method in step S27. In step S28, the power transmission device 10 performs power transmission with the adjusted power transmission capability using the selected driving method. The non-contact power transmission system 1 repeats step S22 to step S28 during a period in which power transmission from the power transmission device 10 to the power reception device 20 is continued. At this time, in step S22, the power transmission side control unit 16 sets the drive voltage of the output unit 30 and the oscillation unit 12 so that the potential information of the power reception side high potential power line 27 transmitted from the power reception device 20 becomes a predetermined value. The frequency and duty ratio of the clock signal Φc are controlled.

  The non-contact power transmission system 1 has the same effects as (1) to (3) exhibited by the non-contact power transmission system 1 of the first embodiment. That is, the effect that a non-contact power transmission system can be realized with a large power supply capacity and low power loss, and that power transmission by an appropriate driving method is executed according to the power consumption of the power receiving device 20 There are effects and other various effects. Moreover, the non-contact power transmission system 1 has the following effects.

  (4) The power transmission device 10 includes a power transmission side detection unit 15 and a power transmission side control unit 16. The power transmission side detection unit 15 detects the potential information of the power reception side high potential power supply line 27 transmitted from the power reception device 20. The power transmission side detection unit 15 compares the power consumption information transmitted from the power receiving device 20 with a predetermined threshold value. The power transmission side control unit 16 controls the frequency and time ratio of the control signal for controlling the generated voltage of the DC voltage generation unit 11 and the clock signal Φc of the oscillation unit 12 based on the detection result of the power transmission side detection unit 15. Output a signal. The power transmission side control unit 16 outputs the switching signal SW of the drive method switching unit 50 based on the comparison result of the power transmission side detection unit 15. According to this configuration, in addition to switching the driving method of the driving unit 40, the power transmission capability of the power transmission device 10 can be adjusted by adjusting the output unit driving voltage, the clock frequency, and the clock time ratio of the driving unit 40. For this reason, the non-contact electric power transmission system which can perform efficient electric power transmission with respect to several power receiving apparatus from which power consumption differs can be implement | achieved.

  (5) The power transmission side detection unit 15 detects the potential information of the power reception side high potential power line 27 transmitted from the power reception device 20. The power transmission side control unit 16 controls the frequency and time ratio of the control signal for controlling the generated voltage of the DC voltage generation unit 11 and the clock signal Φc of the oscillation unit 12 based on the detection result of the power transmission side detection unit 15. Output a signal. According to this configuration, the configuration of the power receiving device 20 can be simplified. For this reason, it can contribute to size reduction of the power receiving apparatus 20.

(Other embodiments)
This non-contact power transmission system includes embodiments other than the first and second embodiments. Hereinafter, the modification of 1st and 2nd embodiment as other embodiment of this non-contact electric power transmission system is shown. The following modifications can be combined with each other.

  The driving method switching unit 50 of the first embodiment sets the signal levels of the driving signals Φp1 and Φn1 to fixed values when the switching signal SW is at a low level. On the other hand, when the switching signal SW is at a low level, the driving method switching unit 70 according to the modified example sets the signal levels of the driving signals Φp2 and Φn2 to fixed values.

With reference to FIG. 7, a circuit configuration of the driving method switching unit 70 will be described.
The drive system switching unit 70 includes a second inverter 71, a third inverter 72, a second NAND gate 73, and a second NOR gate 74.

  The first input portion of the second NAND gate 73 is connected to the output signal of the second inverter 71. A second input portion of the second NAND gate 73 is connected to the switching signal SW. The first input part of the second NOR gate 74 is connected to the output part of the third inverter 72. The second input part of the second NOR gate 74 is connected to the output signal of the second inverter 71.

The input part of the second inverter 71 is connected to the clock signal Φc. The input part of the third inverter 72 is connected to the switching signal SW.
The second NAND gate 73 outputs a drive signal Φp2. The second NOR gate 74 outputs a drive signal Φn2. The second inverter 71 outputs a drive signal Φp1 and a drive signal Φn1.

With reference to FIG. 8, an example of operation | movement of the power transmission apparatus 10 is demonstrated.
The power transmission device 10 performs the same operation as that of the power transmission device 10 of the first embodiment in the period from time t11 to t1 when the power transmission side detection unit 15 outputs the high-level signal SW.

  The power transmission device 10 supplies the output unit 30 with a current corresponding to the difference between the potential of the power transmission side high potential power supply line 17 and the potential of the power transmission side low potential power supply line 18 during the period of time t11 to t1. The power transmission device 10 switches the direction of the current supplied to the output unit 30 according to the level of the clock signal Φc during the period from time t11 to t1 when the power transmission side detection unit 15 outputs the high level switching signal SW. That is, the drive unit 40 forms a full bridge circuit.

The power transmission device 10 performs the following operation during a period from time t1 to time t24 when the power transmission side detection unit 15 outputs the low-level signal SW.
The driving method switching unit 70 operates as follows during the period of time t1 to t21. The drive method switching unit 70 receives the low level signal Φc from the oscillation unit 12 and receives the low level signal SW from the power transmission side detection unit 15. The driving method switching unit 70 performs a logical operation on the low level signal Φc and the low level signal SW, thereby causing the high level driving signal Φp1, the high level driving signal Φp2, the high level driving signal Φn1, and the low level driving signal Φn1. The drive signal Φn2 is output.

  The drive unit 40 operates as follows during the period from time t1 to time t21. The first transistor T1 is turned off when the high-level drive signal Φp1 is input. The second transistor T2 is turned off when the high-level drive signal Φp2 is input. The third transistor T3 is turned on when the high-level drive signal Φn1 is input. The fourth transistor T4 is turned off when the low-level drive signal Φn2 is input.

  The output unit 30 operates as follows during the period from time t1 to t21. The first end 30A of the output unit 30 is connected to the power transmission side high potential power line 17 via the second capacitor C2. The first end 30A of the output unit 30 is connected to the power transmission side low potential power line 18 via the fourth capacitor C4. The second end 30B of the output unit 30 is connected to the power transmission side low potential power line 18 via the third transistor T3.

  The power transmission device 10 was divided by the second capacitor C2 and the fourth capacitor C4 from the first end 30A of the output unit 30 toward the second end 30B of the output unit 30 during the period of time t1 to t21. A current corresponding to the potential of the power transmission side high potential power line 17 and the potential of the power transmission side low potential power line 18 and the potential of the power transmission side low potential power line 18 is supplied.

  The driving method switching unit 70 operates as follows during the period of time t21 to t22. The drive method switching unit 70 receives the high level signal Φc from the oscillation unit 12 and receives the low level signal SW from the power transmission side detection unit 15. The drive system switching unit 70 performs a logical operation on the high-level signal Φc and the low-level signal SW, so that the low-level drive signal Φp1, the high-level drive signal Φp2, the low-level drive signal Φn1, and the low-level drive signal Φn1 The drive signal Φn2 is output.

  The drive unit 40 operates as follows during the period from time t21 to t22. The first transistor T1 is turned on when the low-level driving signal Φp1 is input. The second transistor T2 is turned off when the high-level drive signal Φp2 is input. The third transistor T3 is turned off when the low-level drive signal Φn1 is input. The fourth transistor T4 is turned off when the low-level drive signal Φn2 is input.

  The output unit 30 operates as follows during the period from time t21 to t22. The first end 30A of the output unit 30 is connected to the power transmission side high potential power line 17 via the second capacitor C2. The first end 30A of the output unit 30 is connected to the power transmission side low potential power line 18 via the fourth capacitor C4. The second end 30B of the output unit 30 is connected to the power transmission side high potential power line 17 via the first transistor T1.

  In the period from time t21 to t22, the power transmission device 10 transmits the potential of the power transmission-side high-potential power line 17 and the second capacitor from the second end 30B of the output unit 30 toward the first end 30A of the output unit 30. A current corresponding to the potential of the power transmission side high potential power line 17 and the potential of the power transmission side low potential power line 18 divided by C2 and the fourth capacitor C4 is supplied.

  The drive system switching unit 70, the drive unit 40, and the output unit 30 operate as follows during the period from time t22 to t23. The driving method switching unit 70, the driving unit 40, and the output unit 30 perform the same operation as the operation in the period from time t1 to t21 in the period from time t22 to t23.

  The drive system switching unit 70, the drive unit 40, and the output unit 30 operate as follows during the period from time t23 to t24. The driving method switching unit 70, the driving unit 40, and the output unit 30 perform the same operation as the operation in the period from time t21 to t22 in the period from time t23 to t24.

  For this reason, the power transmission device 10 includes the potential of the power transmission side high potential power line 17, the second capacitor C2, and the fourth capacitor during the period from time t1 to time t24 when the power transmission side detection unit 15 outputs the low level switching signal SW. A current corresponding to the potential of the power transmission side high potential power supply line 17 and the potential of the power transmission side low potential power supply line 18 divided by C4 is supplied to the output unit 30. The power transmission device 10 switches the direction of the current supplied to the output unit 30 according to the level of the clock signal Φc during the period from time t1 to t24 when the power transmission side detection unit 15 outputs the low level switching signal SW. That is, the drive unit 40 forms a half bridge circuit.

  The driving unit 40 according to the first embodiment includes transistors T1 to T4, diodes D1 to D4, and capacitors C1 to C4. On the other hand, the driving unit 40 according to the modification includes transistors T1 to T4 configured by MOSFE formed on a silicon substrate. The diodes D1 to D4 and the capacitors C1 to C4 are configured by substrate diodes and parasitic capacitances that are formed in association with the structures of the transistors T1 to T4.

  In the non-contact power transmission system 1 of the first embodiment and the second embodiment, the power receiving side detection unit 26 detects the power consumption of the power receiving device 20. The power consumption detected by the power receiving side detection unit 26 is transmitted to the power transmission device 10. On the other hand, in the non-contact power transmission system 1 of the modification, the power receiving side detection unit 26 compares the power consumption of the power receiving device 20 with a predetermined threshold value. The power receiving side detection unit 26 transmits the comparison result to the power transmission device 10.

  The contactless power transmission system 1 according to the first embodiment and the second embodiment uses a load modulation method as a transmission method of potential information and power consumption information of the power receiving side high potential power line 27. On the other hand, the non-contact power transmission system 1 of the modified example uses an NFC scheme for short-range wireless communication. Alternatively, other transmission methods are used.

  In the non-contact power transmission system 1 of the first embodiment and the second embodiment, the power transmission side resonance capacitor 31 and the power transmission coil 32, and the power reception side resonance capacitor 62 and the power reception coil 61 are connected in series. On the other hand, in the non-contact power transmission system 1 of the modified example, the power transmission side resonance capacitor 31 and the power transmission coil 32 and the power reception side resonance capacitor 62 and the power reception coil 61 are connected in parallel. Or it is set as the combination of series connection and parallel connection.

  DESCRIPTION OF SYMBOLS 1 ... Non-contact electric power transmission system, 10 ... Power transmission apparatus, 12 ... Oscillation part, 20 ... Power receiving apparatus, 30 ... Output part, 40 ... Drive part, 50 ... Drive system switching part, 70 ... Drive system switching part, (PHI) c ... Clock Signal, T1 ... 1st transistor, T2 ... 2nd transistor, T3 ... 3rd transistor, T4 ... 4th transistor.

Claims (7)

A power transmission device for a non-contact power transmission system,
The power transmission device includes an output unit, an oscillation unit, a drive unit, and a drive system switching unit,
The output unit transmits power based on a signal output from the drive unit,
The oscillating unit outputs a clock signal to the driving unit,
The driving unit drives the output unit by a first driving method or a second driving method having different power transmission capabilities,
The drive method switching unit is a power transmission device of a non-contact power transmission system that selects the first drive method or the second drive method according to power consumption information of a power receiving device. The power transmission device changes the at least one of an output unit driving voltage, which is a voltage input to the driving unit, a frequency of the clock signal, and a time ratio of the clock signal, to thereby change the first driving method. The power transmission device of the non-contact power transmission system according to claim 1, wherein the power transmission capability of the second drive method is adjusted. The power transmission apparatus of the non-contact power transmission system according to claim 1, wherein the driving unit has a half-bridge driving method as the first driving method and a full-bridge driving method as the second driving method. The driving unit includes a plurality of transistors for driving the output unit,
The contactless power transmission according to any one of claims 1 to 3, wherein the drive method switching unit selects the first drive method or the second drive method by outputting a clock signal to the plurality of transistors. System power transmission equipment. The power transmission device according to any one of claims 1 to 4,
A non-contact power transmission system having a power receiving device. A power transmission capacity adjustment method for a non-contact power transmission system,
The contactless power transmission system includes:
A power transmission device and a power reception device;
The power transmission device is:
Having a first drive method and a second drive method with different power transmission capabilities,
The power transmission capacity adjustment method includes:
Detecting the power consumption of the power receiving device in the power receiving device;
Transmitting the detection result of the power consumption from the power receiving device to the power transmitting device;
A method for adjusting a power transmission capability of a non-contact power transmission system, comprising: selecting one of the first driving method and the second driving method based on a detection result of the power consumption. The power transmission capacity adjustment method includes:
The non-contact power according to claim 6, comprising a step of changing at least one of an output unit driving voltage of the power transmission device, a frequency of the output unit driving clock signal, and a time ratio of the output unit driving clock signal. A method for adjusting the power transmission capacity of a transmission system.