JP5348081B2 - Non-contact power receiving device - Google Patents

Description

  The present invention relates to a non-contact power receiving device that is mounted on a transport vehicle and receives power from a power feeding device in a non-contact manner.

  As miniaturization, recovery, and high functionality of semiconductor devices progress, clean rooms where they are manufactured are required to have high dust-freeness for microfabrication and multiple processes and high efficiency of each process. . In recent years, automatic guided vehicles have been frequently used to play this role.

  FIG. 9 is an external view of a conventional unmanned conveyance system. The unmanned conveyance system in the figure includes a non-contact power supply device 700, a non-contact power reception device 800, and a traveling rail 900.

  The non-contact power supply apparatus 700 includes a non-contact power supply circuit 710, a non-contact power supply line 720, and a power supply line holder 730. The non-contact power supply circuit 710 generates an alternating current for driving the drive motor of the non-contact power receiving apparatus 800 and supplies it to the non-contact power supply line 720. The non-contact power supply line 720 is fixed by a power supply line holder 730 fixed on the floor surface, and allows an alternating current supplied from the non-contact power supply circuit 710 to flow. The non-contact power receiving apparatus 800 is an automatic guided vehicle, and includes a core 810 and a pickup coil 820 on the lower outer side. The core 810 is disposed so as to surround the two parallel non-contact power supply lines 720. A pickup coil 820 is disposed on the surface of the core 810 that is closest to the non-contact power supply line 720. By this arrangement and electromagnetic induction due to the alternating current of the non-contact power supply line 720, the non-contact power receiving device 800 receives supply of AC power from the non-contact power supply line 720 via the pickup coil 820. That is, the primary side circuit that is the non-contact power feeding circuit 710 and the secondary side circuit to which the motor of the non-contact power receiving device 800 is connected are provided in a non-contact state. The high-frequency alternating current that flows to the power supply line of the side circuit is extracted from the pickup coil by using electromagnetic action to supply constant voltage power to a load such as a motor.

  FIG. 10A and FIG. 10B are examples of functional configuration diagrams of a conventional non-contact power receiving device, respectively. The contactless power receiving device described in FIG. 10A rectifies AC power received by a pickup core by a rectifier circuit via a passive element, and finally uses a chopper circuit to supply a predetermined DC voltage to the load side. It is a method to supply to. In addition, the non-contact power receiving device described in FIG. 10B first receives AC power output from the primary circuit by a pickup core, and uses the pickup core and a passive element to generate a predetermined AC voltage. Then, the predetermined AC voltage is rectified by a rectifier circuit to generate a predetermined DC voltage and supplied to the load side.

  FIG. 11 is a circuit configuration diagram of a conventional non-contact power receiving device described in Patent Document 1. A non-contact power receiving device 800 shown in the figure includes a pickup core 801, capacitors 802, 803 and 806, a reactor 804, a rectifier circuit 805, and a load 807. The non-contact power receiving device 800 corresponds to the method described in FIG. 10B, and has a series resonance type circuit configuration using the pickup core 801 as a constant voltage source, and includes a primary side circuit and a secondary side circuit. The voltage extracted in the voltage conversion usually depends on the magnitude of the inductance of the pickup core 801. Therefore, in order to set the voltage of the secondary side circuit according to the specification of the load 807, the pickup 806 can be connected to the pickup core 801 in parallel without increasing the number of turns of the pickup core 801. The substantial inductance of the core 801 is adjusted. In order to supply power stably to the load 807, the AC voltage obtained by the pickup core 801, the capacitors 802, 803 and 806, and the reactor 804 is converted into a direct current by the rectifier circuit 805 and the smoothing capacitor 806. Converting to voltage.

JP 2004-194443 A

  However, in the non-contact power receiving device 800 described in Patent Document 1, which is the method illustrated in FIG. 10B, the AC power received by the pickup core 801 corresponds to the voltage specification of the load 807, so that it is not shipped. Large capacity adjustment of the capacitors 802 and 803 is required. In addition, the capacitors 802 and 803 and the reactor 804 are power elements having a relatively large volume, and limit the size reduction of the non-contact power receiving apparatus, and hence the transport vehicle.

  Further, in the non-contact power receiving apparatus of the method described in FIG. 10A, it is necessary to use active elements such as diodes and switching elements in two circuits, a rectifier circuit and a chopper circuit, respectively. The score will increase.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a non-contact power receiving apparatus that can obtain a predetermined voltage with a small number of parts and that can easily adjust a circuit.

  In order to achieve the above object, a contactless power receiving device according to one embodiment of the present invention is a contactless power receiving device that receives power from a power feeding device via a power feeding line in a contactless manner, and flows through the power feeding line. A pickup core that receives AC power from the power supply line by electromagnetic induction by AC current, and rectifies the AC power received from the power supply line and performs chopper control to generate a predetermined DC voltage to the load. One switching unit to supply is provided.

  By adopting this configuration, since one switching unit serves both as a rectifying function and a chopper control function, it is possible to supply a predetermined voltage to the load with a small number of parts.

  The switching unit is a single-phase bridge circuit composed of four diode elements, and a semiconductor switch element for short-circuiting between the terminals of the diode elements is connected in parallel to each of the four diode elements. The non-contact power receiving apparatus further includes a control unit that controls conduction and non-conduction of the four semiconductor switch elements, and the control unit is synchronized with AC power received from the feeder line. Two of the semiconductor switch elements are simultaneously turned on or off, and the other two semiconductor switch elements are exclusively turned on or off at the same time. The switching unit rectifies the AC power received from the feeder line, and the four semiconductors By adjusting the timing of the switch element non-conductive, it is preferable to supply a predetermined voltage to the load.

  Thereby, since the switching unit is comprised by the bridge circuit marketed as one component, it becomes possible to reduce the number of circuit components which comprise a non-contact electric power receiving apparatus. Furthermore, the rectification function and the chopper control function of the switching unit can be realized only by controlling the conduction and non-conduction of the semiconductor switch element added to the bridge circuit. Therefore, large-scale capacity adjustment such as a capacitor is not required at the time of shipment, and the DC voltage supplied to the load can be adjusted by a simple operation by the control unit.

  In addition, the control unit further regenerates from the load side via the switching unit by adjusting the timing at which the four semiconductor switch elements are made non-conductive in synchronization with the AC power received from the feeder line. By returning the current to the pickup core, the power corresponding to the regenerative current may be returned to the power feeding device.

  When the direction of the effective current flowing through the load side is opposite to the DC voltage supplied to the load side, the load side current can be returned to the pickup core as a regenerative current. This regenerative current can be generated by providing a predetermined delay time with respect to the phase of the AC voltage generated in the pickup core at a timing when the four semiconductor switch elements added to the bridge circuit are made non-conductive. Become.

  Thereby, it becomes possible to return electric power to the power supply apparatus which is a primary side, and power saving is achieved.

  The switching unit is a single-phase bridge circuit composed of four diode elements, and each of the two diode elements of the four diode elements is for short-circuiting between the terminals of the diode elements. Semiconductor switch elements are connected in parallel, and the non-contact power receiving device further includes a control unit that controls conduction and non-conduction of the two semiconductor switch elements, and the control unit receives AC from the power supply line. Synchronously with power, both the semiconductor switch elements are simultaneously turned on or off at the same time, thereby causing the switching unit to rectify AC power received from the feeder line, and at the same time as the simultaneous conduction period. A predetermined voltage may be supplied to the load by adjusting a ratio with the non-conduction period.

  Also in this configuration, since the switching unit is configured by a bridge circuit that is commercially available as one component, the number of circuit components that configure the non-contact power receiving apparatus can be reduced.

  According to the present invention, since a single switching unit can be used for both rectification control and chopper control, a predetermined voltage can be obtained with a small number of parts, and a non-contact power receiving apparatus that can easily adjust a circuit can be provided.

It is a circuit block diagram of the non-contact power receiving apparatus which concerns on Embodiment 1 of this invention. It is a timing chart showing the circuit operation | movement of the non-contact power receiving apparatus which concerns on Embodiment 1 of this invention. It is a circuit state transition diagram of the non-contact power receiving device according to the first embodiment of the present invention. It is a circuit block diagram of the non-contact power receiving apparatus which concerns on Embodiment 2 of this invention. It is a timing chart showing the circuit operation | movement at the time of the power reception of the non-contact power receiving apparatus which concerns on Embodiment 2 of this invention. It is a circuit state transition diagram at the time of the power reception of the non-contact power receiving apparatus which concerns on Embodiment 2 of this invention. It is a timing chart showing circuit operation at the time of regeneration of a non-contact power receiving device concerning Embodiment 2 of the present invention. It is a circuit state transition diagram at the time of regeneration of the non-contact power receiving device concerning Embodiment 2 of the present invention. It is an external view of the conventional unmanned conveyance system. (A) is an example of the functional block diagram of the conventional non-contact power receiving apparatus. (B) is an example of the functional block diagram of the conventional non-contact power receiving apparatus. It is a circuit block diagram of the conventional non-contact power receiving apparatus described in Patent Document 1.

(Embodiment 1)
Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a circuit configuration diagram of a non-contact power receiving apparatus according to Embodiment 1 of the present invention. The non-contact power receiving apparatus 1 in FIG. 1 includes a pickup core 11, capacitors 12 and 14, a switching unit 13, a load 15, and a control unit 16.

  The pickup core 11 receives AC power from the non-contact power supply device by electromagnetic induction caused by an AC current of a power supply line included in the non-contact power supply device. That is, the primary side circuit that is a non-contact power feeding device and the secondary side circuit to which the motor of the non-contact power receiving device 1 is connected are provided in a non-contact state, and the non-contact power receiving device 1 The high-frequency alternating current that flows to the power supply line of the circuit is extracted from the pickup core 11 that is the secondary side circuit by using electromagnetic action.

  The pickup core 11 and the capacitor 12 arranged in series constitute a series resonance unit.

  The switching unit 13 is connected to the subsequent stage of the series resonance unit, and has a function of rectifying AC power output from the series resonance unit, generating a predetermined DC voltage, and supplying it to a load. The switching unit 13 forms a single-phase bridge circuit with four diodes 131, 132B, 133, and 134B, and switching transistors 132A and 134A for short-circuiting between the diode terminals are connected in parallel to the diodes 132B and 134B, respectively. ing. The switching transistors 132A and 134A are controlled so as to be simultaneously conductive and simultaneously non-conductive, and are supplied to the load 15 and the capacitor 14 by adjusting the ratio between the period of the conductive state and the period of the non-conductive state. The amplification factor of the DC voltage is determined.

  The capacitor 14 has a function of smoothing the voltage rectified by the switching unit 13 and using the voltage across the load 15 as a smoothed DC voltage.

  The load 15 is operated by consuming the electric power when supplied with the electric power specified by the DC voltage, and is, for example, a motor that drives the wheels of the automatic guided vehicle.

The control unit 16 is constituted by a CPU, for example, and has a function of controlling conduction and non-conduction of the switching transistors 132A and 134A in synchronization with the power receiving side input current I ₂₁ flowing through the pickup core 11.

  Hereinafter, the power receiving operation of the non-contact power receiving apparatus 1 according to the first embodiment of the present invention will be described.

FIG. 2 is a timing chart showing the circuit operation of the non-contact power receiving apparatus according to Embodiment 1 of the present invention. In the timing chart shown in the figure, the power receiving side output current I ₂₂₁ flowing into the contact C, the load current I ₂₂₂ flowing through the contact C → the load 15 → the contact D, and the contact C → the capacitor 14 → the contact D flowing from the top. One cycle T of the capacitor current I ₂₂₃ , the conduction state of the switching transistors 132A and 134A, the power receiving side input current I ₂₁ flowing through the pickup core 11 and the capacitor 12, the voltage V ₂₁ across the pickup core 11, and the power supply side output current I ₁ The time change in is represented. The voltage value and current value on the vertical axis are relative displays. Voltage across V ₂₁ of the power receiving side input current I ₂₁ and the pickup core 11 by the electromagnetic induction power sourcing output current I ₁ is a sine wave, has a sinusoidal wave phase-shifted with respect to the feed-side output current I ₁ .

  FIG. 3 is a circuit state transition diagram of the non-contact power receiving apparatus according to Embodiment 1 of the present invention.

First, at time t01, the control unit 16 turns off the switching transistors 132A and 134A. At this moment, the current loop flowing through the non-contact power receiving device 1 is a path of pickup core 11 → capacitor 12 → contact A → diode 131 → contact C → load 15 and capacitor 14 → contact D → diode 134B → contact B → pickup core 11. To change. At this moment, the power receiving side output current I ₂₂₁ becomes maximum. The circuit state from time t01 to time t02 corresponds to the state from t01 to t02 shown in FIG. Further, during this period, the capacitor current I ₂₂₃ becomes a current reflecting a fluctuation component of the power receiving side output current I ₂₂₁ , and thereby a DC load current I ₂₂₂ flows through the load 15.

In a period Toff from time t01 to time t02, the rectified power-receiving-side input current I ₂₂₁ is supplied from the contact C toward the contact D toward the load 15 and the capacitor 14, and the voltage V _CD between the contact C and the contact D is supplied. Is smoothed. In this period, the power receiving side input current I ₂₂₁ gradually decreases.

Next, at time t02, the control unit 16 turns on the switching transistors 132A and 134A. At this moment, the current loop flowing through the non-contact power receiving device 1 changes in the path of pickup core 11 → contact B → switching transistor 134A → switching transistor 132A → contact A → capacitor 12 → pickup core 11. The circuit state from time t02 to time t03 corresponds to the state from t02 to t03 shown in FIG. Further, in the period Ton from time t02 to time t03, the power receiving side output current I ₂₂₁ does not flow, but the closed loop current flows to the load 15 due to the charge charged in the capacitor 14 in advance, so that the load current I ₂₂₂ is before the time t02. The direct current that was flowing in is maintained.

Next, at time t03, the control unit 16 turns off the switching transistors 132A and 134A. At this moment, the current loop flowing through the non-contact power receiving device 1 is a path of pickup core 11 → contact B → diode 133 → contact C → load 15 and capacitor 14 → contact D → diode 132B → contact A → capacitor 12 → pickup core 11. To change. At this moment, the power receiving side output current I ₂₂₁ becomes maximum. The circuit state from time t03 to time t04 corresponds to the state from t03 to t04 described in FIG. Further, during this period, the capacitor current I ₂₂₃ becomes a current reflecting a fluctuation component of the power receiving side output current I ₂₂₁ , and thereby a DC load current I ₂₂₂ flows through the load 15.

In the period Toff from time t03 to time t04, the power receiving side input current I ₂₂₁ rectified from the contact C toward the contact D is supplied to the load 15 and the capacitor 14, and the voltage VCD between the contact C and the contact D is smooth. It becomes. In this period, the power receiving side input current I ₂₂₁ gradually decreases.

Next, at time t04, the control unit 16 makes the switching transistors 132A and 134A conductive. At this moment, the current loop flowing through the non-contact power receiving device 1 changes in the path of pickup core 11 → capacitor 12 → contact A → switching transistor 132A → switching transistor 134A → contact B → pickup core 11. The circuit state from time t04 to time T and from time 0 to time t01 corresponds to the state from t04 to t to T and from 0 to t to time t01 described in FIG. Further, during the period Ton from time t04 to time T and from time 0 to time t01, the power receiving side output current I ₂₂₁ does not flow, but a closed loop current flows to the load 15 due to the charge previously charged in the capacitor 14, thereby causing the load current to flow. I ₂₂₂ maintains the direct current flowing before time t04.

The power P _CD supplied to the load 15 and the capacitor 14 is determined by the product of the power receiving side input current I ₂₂₁ flowing from the contact C to the contact D in the period Toff and the smoothed voltage V _CD . The magnitude of the voltage V _CD supplied to the load 15 is determined by the ratio between the period Toff and the period Ton in which the switching transistors 132A and 134A are in the conductive state.

That is, the switching unit 13 is configured such that the switching transistors 132A and 134A, which are constituent elements thereof, are simultaneously turned on and off at a predetermined timing, so that the power receiving side input current I ₂₁ that is an alternating current is changed from the contact C to the contact D. A rectifying function for flowing only in one direction, and a chopper function for adjusting the voltage V _CD between the contact C and the contact D to a predetermined voltage.

  In the conventional non-contact power receiving apparatus, for example, the circuit configuration described in FIG. 11, six circuit components are required, that is, a pickup core 801, a capacitor 802, a capacitor 803, a capacitor 806, a reactor 804, and a rectifier circuit 805. .

On the other hand, in the circuit configuration of the non-contact power receiving device according to the first embodiment of the present invention, four points of the pickup core 11, the capacitor 12, the capacitor 14, and the switching unit 13 are necessary as circuit components. By combining the rectifying function and the chopper function of the switching unit 13 described above, the number of parts can be reduced. Furthermore, the load voltage can be set only by setting the conduction and non-conduction timings of the switching transistors constituting the switching unit 13 in synchronization with the power-receiving-side input current I ₂₁ without requiring large capacity adjustment of the capacitors at the time of shipment. It becomes possible to adjust to a predetermined voltage.

(Embodiment 2)
Hereinafter, Embodiment 2 of the present invention will be described in detail with reference to the drawings.

  FIG. 4 is a circuit configuration diagram of the contactless power receiving device according to the second embodiment of the present invention. The non-contact power receiving device 2 in FIG. 1 includes a pickup core 11, capacitors 12 and 14, a switching unit 23, a load 15, and a control unit 26. Compared with the non-contact power receiving device 1 described in the first embodiment, the non-contact power receiving device 2 described in the figure is different only in the circuit configuration of the switching unit. Hereinafter, description of the same points as in the first embodiment will be omitted, and only different points will be described.

  The switching unit 23 is connected to the subsequent stage of the series resonance unit composed of the pickup core 11 and the capacitor 12, rectifies the AC power output from the series resonance unit, and generates a predetermined DC voltage to load 15 The function to supply to.

  The switching unit 23 forms a single-phase bridge circuit by four diodes 231B, 232B, 233B, and 234B. Furthermore, switching transistors 231A, 232A, 233A, and 234A for short-circuiting the diode terminals are connected in parallel to the four diodes 231B, 232B, 233B, and 234B, respectively.

  The switching transistors 231A and 234A are controlled to be conductive and non-conductive at the same time, and the switching transistors 232A and 233A are controlled to be conductive and non-conductive at the same time. The conduction state of the transistors 232A and 233A is realized exclusively. Thereby, the switching unit 23 rectifies the AC power received from the feeder line. A predetermined DC voltage is supplied to the load 15 at the timing when the four switching transistors are turned off.

The control unit 26 is composed of, for example, a CPU, and has a function of controlling conduction and non-conduction of the four switching transistors in synchronization with the power receiving side input current I ₂₁ flowing through the pickup core 11. Here, the control unit 26 adjusts the timing at which the four switching transistors are turned off, thereby (1) supplying predetermined power to the load 15 and (2) the switching unit 23 from the load 15 side. When the electric power corresponding to the regenerative current is returned to the power feeding device by returning the regenerative current to the pickup core 11 via the.

  Hereinafter, the power receiving operation and the regenerative operation of the non-contact power receiving apparatus 2 according to Embodiment 2 of the present invention will be described.

FIG. 5 is a timing chart showing a circuit operation during power reception of the non-contact power reception device according to Embodiment 2 of the present invention. In the timing chart shown in the figure, the power receiving side output current I ₂₂₁ flowing into the contact C, the load current I ₂₂₂ flowing through the contact C → the load 15 → the contact D, and the contact C → the capacitor 14 → the contact D flowing from the top. Capacitor current I ₂₂₃ , switching transistors 231A, 232A, 233A and 234A conducting, power receiving side input current I ₂₁ flowing through the pickup core 11 and capacitor 12, voltage V ₂₁ across the pickup core 11, and power supply side output current I ₁ , Represents a time change in one cycle T. The voltage value and current value on the vertical axis are relative displays. Voltage across V ₂₁ of the power receiving side input current I ₂₁ and the pickup core 11 by the electromagnetic induction power sourcing output current I ₁ is a sine wave, has a sinusoidal wave phase-shifted with respect to the feed-side output current I ₁ .

  FIG. 6 is a circuit state transition diagram at the time of power reception of the non-contact power reception device according to Embodiment 2 of the present invention.

  First, at time t11, the control unit 26 turns off the switching transistors 232A and 233A. At this moment, the current loop flowing through the non-contact power receiving device 2 is a path of pickup core 11 → capacitor 12 → contact A → diode 231B → contact C → load 15 and capacitor 14 → contact D → diode 234B → contact B → pickup core 11. To change. The circuit state from time t11 to time t121 corresponds to the state from t11 to t121 described in FIG.

At this time, the power receiving side output current I ₂₂₁ flowing through the load 15 and the capacitor 14 changes sharply from the negative direction (contact D → contact C) to the positive direction (contact C → contact D), and the circuit of the non-contact power receiving apparatus 2 _Acts to increase the supply voltage V _CD to the load and capacitor 14. With this action and the smoothing action of the capacitor 14, V _CD can be maintained at a constant voltage. Further, during this period, the capacitor current I ₂₂₃ becomes a current reflecting the fluctuation component of the power receiving side output current I ₂₂₁ , and thereby the load current I ₂₂₂ is maintained at the DC current flowing before the time t 11.

  Next, at time t121, the control unit 26 turns on the switching transistors 231A and 234A. Thereby, the current loop flowing through the non-contact power receiving device 2 maintains the path of the current loop at time t11 to t121. The circuit state from time t121 to time t122 corresponds to the state from t121 to t122 described in FIG.

Next, from time t122 to time t13, the current loop flowing through the non-contact power receiving device 2 is as follows: pickup core 11 → contact B → switching transistor 234A → contact D → capacitor 14 → contact C → switching transistor 231A → contact A → capacitor 12 → Changes to the path of the pickup core 11. On the other hand, the DC load current I ₂₂₂ that has flowed from time t121 to time t122 flows through the load 15 due to the voltage V _CD smoothed by the capacitor 14. The circuit state from time t122 to time t13 corresponds to the state from t122 to t13 shown in FIG.

In the period from time t11 to time t13, the power receiving side output current I ₂₂₁ continuously decreases its absolute value and finally flows in the negative direction (contact D → contact C). However, the power receiving side output current I ₂₂₁ in the above period is a current that flows in the positive direction (contact C → contact D) as an integrated effective current.

  Next, at time t13, the control unit 26 turns off the switching transistors 231A and 234A. At this moment, the current loop flowing through the non-contact power receiving device 2 is a path of pickup core 11 → contact B → diode 233B → contact C → load 15 and capacitor 14 → contact D → diode 232B → contact A → capacitor 12 → pickup core 11. To change. The circuit state from time t13 to time t141 corresponds to the state from t13 to t141 described in FIG.

At this time, the power receiving side output current I ₂₂₁ flowing through the load 15 and the capacitor 14 changes sharply from the negative direction (contact D → contact C) to the positive direction (contact C → contact D), and the circuit of the non-contact power receiving apparatus 2 _Acts to increase the supply voltage V _CD to the load and capacitor 14. With this action and the smoothing action of the capacitor 14, V _CD can be maintained at a constant voltage. Further, during this period, the capacitor current I ₂₂₃ becomes a current reflecting the fluctuation component of the power receiving side output current I ₂₂₁ , and thereby the load current I ₂₂₂ is maintained at the DC current flowing before time t 13.

When the power receiving side output current I ₂₂₁ is in the positive direction (contact C → contact D) as the effective current during the period from time t11 to time t13 with respect to the DC voltage V _CD applied to the load 15 and the capacitor 14, the load 15 And the capacitor 14 is supplied with electric power defined by V _CD and the effective current, and the electric power is consumed by the load 15 as necessary. In this case, for example, when the control unit 26 monitors the fluctuation of V _CD and determines that the power receiving mode is set, I ₂₂₁ flows in the positive direction (contact C → contact D) as an effective current in the period T. The timing at which the switching transistors 232A and 233A are made non-conductive and the timing at which the switching transistors 231A and 234A are made non-conductive are the delay amounts from the phase of the power receiving side input current I ₂₁ and the voltage V ₂₁ across the pickup core 11. adjust.

Specifically, when the control unit 26 determines that the power receiving mode is in effect, the control unit 26 sets the phase relationship between the power receiving side input current I ₂₁ and the virtual sine wave due to on / off of the switching transistor within a predetermined range. The on / off timing of the switching transistor is adjusted so that Further, at the rising edge of the power reception mode, that is that the load 15 is not operating, the control unit 26, the voltage across V ₂₁ small pickup core 11 instead, the variation in the time of no load on the receiving side input current I ₂₁ And the on / off timing of the switching transistor are adjusted so that the phase relationship between the switching transistor and the virtual sine wave due to on / off of the switching transistor is within a predetermined range.

  Here, the virtual sine wave means that the positive peak (phase 90 °) or negative peak (phase 270 °) of the sine wave is obtained at the midpoint of the ON state of the pulse waveform generated by turning on / off the switching transistor. It is defined as a sine wave that is regarded as the time to be measured.

In FIG. 5, for example, the positive peak point E of the virtual sine wave is delayed in phase by about 225 ° with respect to the negative peak point F of the voltage V ₂₁ across the pickup core 11, and the receiving side input current The phase is delayed by about 135 ° with respect to the negative peak point G of I ₂₁ .

That is, the control unit 26 delays the phase difference between the virtual sine wave and V ₂₁ or I ₂₁ described above by a predetermined range (for example, the positive peak point of the virtual sine wave is delayed by 225 ° from the negative peak point of V ₂₁ . Or by delaying by 135 ° from the negative peak point of I ₂₁ ), it is possible to make the power receiving side output current I ₂₂₁ in the positive direction (contact C → contact D) as an effective current in the period T. Become. As a result, in the power receiving mode, the load 15 and the capacitor 14 are supplied with electric power defined by V _CD and the effective current, and the electric power is consumed by the load 15 as necessary.

  Next, at time t141, the control unit 26 turns on the switching transistors 232A and 233A. Thereby, the current loop flowing through the non-contact power receiving device 2 maintains the path of the current loop from time t13 to t141. The circuit state from time t141 to time t142 corresponds to the state from t141 to t142 described in FIG.

The power P _CD supplied to the load 15 and the capacitor 14, the effective current of the power receiving side input current I ₂₂ flowing through the contact point D from the contact C in period T, is determined by the product of the voltage V _CD smoothed The The magnitude of the voltage V _CD supplied to the load 15 is determined by the timing at which the four switching transistors are turned off.

Next, from time t142 to time T and from time 0 to time t11, the current loop flowing through the non-contact power receiving device 2 is: pickup core 11 → capacitor 12 → contact A → switching transistor 232A → contact D → capacitor 14 → contact. The path changes from C to switching transistor 233A to contact B to the pickup core 11. On the other hand, the DC load current I ₂₂₂ that has flowed from time t141 to time t142 flows through the load 15 by the voltage V _CD smoothed by the capacitor 14. Circuit states at time t142 to time T and from time 0 to time t11 correspond to states t142 to t to T (0 to t11) described in FIG.

During the period from time t13 to time T, the power receiving side output current I ₂₂₁ continuously decreases its absolute value and finally flows in the negative direction (contact D → contact C). However, the power receiving side output current I ₂₂₁ in the above period is a current that flows in the positive direction (contact C → contact D) as an integrated effective current.

As described above, the switching unit 13 is configured such that the four switching transistors as its constituent elements become non-conductive at a predetermined timing, whereby the power receiving side input current I ₂₁ , which is an alternating current, is converted from the contact C to the contact C as an effective current. A rectifying function that flows to D, and a chopper function that adjusts the voltage V _CD between the contact C and the contact D to a predetermined voltage.

  In the conventional non-contact power receiving apparatus, for example, the circuit configuration described in FIG. 11, six circuit components are required, that is, a pickup core 801, a capacitor 802, a capacitor 803, a capacitor 806, a reactor 804, and a rectifier circuit 805. .

On the other hand, in the circuit configuration of the non-contact power receiving apparatus 2 according to the second embodiment of the present invention, four points of the pickup core 11, the capacitor 12, the capacitor 14, and the switching unit 23 are necessary as circuit components. By combining the rectifying function and the chopper function of the switching unit 23 described above, the number of parts can be reduced. In addition, the capacitor does not require large capacitance adjustment at the time of shipment, and the on / off timing of the switching transistor constituting the switching unit 23 is set in synchronization with the power receiving side input current I ₂₁ and the voltage V ₂₁ across the pickup core 11. Only by this, the load voltage can be adjusted to a predetermined voltage.

FIG. 7 is a timing chart showing circuit operation during regeneration of the non-contact power receiving apparatus according to Embodiment 2 of the present invention. In the timing chart shown in the figure, the power receiving side output current I ₂₂₁ flowing into the contact C, the load current I ₂₂₂ flowing through the contact C → the load 15 → the contact D, and the contact C → the capacitor 14 → the contact D flowing from the top. Capacitor current I ₂₂₃ , switching transistors 231A, 232A, 233A and 234A conducting, power receiving side input current I ₂₁ flowing through the pickup core 11 and capacitor 12, voltage V ₂₁ across the pickup core 11, and power supply side output current I ₁ , Represents a time change in one cycle T. The voltage value and current value on the vertical axis are relative displays. Voltage across V ₂₁ of the power receiving side input current I ₂₁ and the pickup core 11 by the electromagnetic induction power sourcing output current I ₁ is a sine wave, has a sinusoidal wave phase-shifted with respect to the feed-side output current I ₁ .

  FIG. 8 is a circuit state transition diagram during regeneration of the non-contact power receiving apparatus according to Embodiment 2 of the present invention.

First, at time t21, the control unit 26 turns off the switching transistors 231A and 234A. At this moment, the current loop flowing through the non-contact power receiving device 2 changes to a path of pickup core 11 → contact B → diode 233B → contact C → capacitor 14 → contact D → diode 232B → contact A → capacitor 12 → pickup core 11. . On the other hand, due to the voltage V _CD smoothed by the capacitor 14, a DC load current I ₂₂₂ that flows before time t 21 flows through the load 15. The circuit state from time t21 to time t22 corresponds to the state from t21 to t22 shown in FIG.

At this time, the power receiving side output current I ₂₂₁ flowing through the load 15 and the capacitor 14 changes sharply from the negative direction (contact D → contact C) to the positive direction (contact C → contact D), and the circuit of the non-contact power receiving apparatus 2 _Acts to increase the supply voltage V _CD to the load and capacitor 14. With this action and the smoothing action of the capacitor 14, V _CD can be maintained at a constant voltage.

Next, at time t22, the control unit 26 turns on the switching transistors 232A and 233A. Thereby, the current loop flowing through the non-contact power receiving device 2 is as follows: pickup core 11 → capacitor 12 → contact A → switching transistor 232A → contact D → capacitor 14 and load 15 → contact C → switching transistor 233A → contact B → pickup core 11 It changes to the path. Further, during this period, the capacitor current I ₂₂₃ becomes a current reflecting the fluctuation component of the power receiving side output current I ₂₂₁ , and thereby the load current I ₂₂₂ is maintained as a direct current flowing from the time t21 to the time t22. The The circuit state from time t22 to time t23 corresponds to the state from t22 to t23 shown in FIG.

Next, at time t23, the control unit 26 turns off the switching transistors 232A and 233A. At this moment, the current loop flowing through the non-contact power receiving device 2 passes through the path of pickup core 11 → capacitor 12 → contact A → diode 231B → contact C → capacitor 14 → contact D → diode 234B → contact B → pickup core 11. On the other hand, a DC load current I ₂₂₂ that flowed before time t23 flows through the load 15 by the voltage V _CD smoothed by the capacitor 14. The circuit state from time t23 to time t24 corresponds to the state from t23 to t24 shown in FIG.

At this time, the power receiving side output current I ₂₂₁ flowing through the load 15 and the capacitor 14 changes sharply from the negative direction (contact D → contact C) to the positive direction (contact C → contact D), and the circuit of the non-contact power receiving apparatus 2 _Acts to increase the supply voltage V _CD to the load and capacitor 14. With this action and the smoothing action of the capacitor 14, V _CD can be maintained at a constant voltage. In the period from time t21 to time t23, the power receiving side output current I ₂₂₁ continuously decreases its absolute value, and finally becomes in the negative direction (contact D → contact C). In addition, the power receiving side output current I ₂₂₁ in the above period is a current that flows in the negative direction (contact D → contact C) as an effective current.

When the power receiving side output current I ₂₂₁ is in the negative direction (contact D → contact C) as the effective current during the period from time t21 to time t23 with respect to the DC voltage V _CD applied to the load 15 and the capacitor 14, the power receiving side The output current I ₂₂₁ can be returned to the pickup core as a regenerative current.

In this case, for example, when the control unit 26 monitors the fluctuation of V _CD and determines that the current mode is the regenerative mode, I ₂₂₁ flows in the negative direction (contact D → contact C) as an effective current in the period T. timing of the switching transistors 232A and 233A in a non-conductive, and, adjusting the switching transistors 231A and 234A of the timing of non-conductive, as the delay amount from the phase of the voltage across V ₂₁ of the power receiving side input current I ₂₁ and the pickup core 11 To do.

Specifically, when the control unit 26 determines that the regeneration mode is set, the control unit 26 sets the phase relationship between the power-receiving-side input current I ₂₁ and the virtual sine wave due to on / off of the switching transistor within a predetermined range. The on / off timing of the switching transistor is adjusted so that Also, the time of rising of the regenerative mode, i.e. that the load 15 is not operating, the control unit 26, the voltage across V ₂₁ of the power receiving side input current I ₂₁ in place of, the variation in the no-load small pickup core 11 And the on / off timing of the switching transistor are adjusted so that the phase relationship between the switching transistor and the virtual sine wave due to on / off of the switching transistor is within a predetermined range.

In FIG. 7, for example, the positive peak point H of the virtual sine wave is delayed in phase by about 45 ° with respect to the positive peak point J of the voltage V ₂₁ across the pickup core 11, and the power receiving side input current The phase is advanced by about 45 ° with respect to the positive peak point K of I ₂₁ .

That is, the control unit 26 delays the phase difference between the above-described virtual sine wave and V ₂₁ or I ₂₁ by a predetermined range (for example, the positive peak point of the virtual sine wave is delayed by 45 ° from the positive peak point of V ₂₁ . Alternatively, the power reception-side output current I _{221 is set} to the negative direction (contact D → contact C) as an effective current by maintaining the phase at 45 ° from the positive peak point of I _21. It becomes possible. As a result, in the regenerative mode, it is possible to return the power defined by V _CD and the effective current from the load 15 and the capacitor 14 to the power feeding device side.

Next, at time t24, the control unit 26 turns on the switching transistors 231A and 234A. Thereby, the current loop flowing through the non-contact power receiving device 2 is as follows: pickup core 11 → contact B → switching transistor 234A → contact D → capacitor 14 and load 15 → contact C → switching transistor 231A → contact A → capacitor 12 → pickup core 11 It changes to the path. Further, during this period, the capacitor current I ₂₂₃ becomes a current reflecting the fluctuation component of the power receiving side output current I ₂₂₁ , whereby the load current I ₂₂₂ is maintained as a DC current flowing from the time t23 to the time t24. The Circuit states at time t22 to time t23 and from time 0 to time t21 correspond to states t24 to t to T (0 to t to t21) illustrated in FIG.

  As described above, according to the non-contact power receiving device according to the second embodiment of the present invention, the rectification function and chopper of the switching unit are controlled only by controlling the conduction and non-conduction of the switching transistor added to the switching unit. A control function can be realized. In addition, by adjusting the timing at which the switching transistor is turned off, it is possible to select a power reception mode for supplying a constant voltage to the load and a regeneration mode for returning power to the power supply apparatus.

  Therefore, large-scale capacity adjustment such as a capacitor is not required at the time of shipment, and the DC voltage supplied to the load can be adjusted by a simple operation by the control unit. Furthermore, the power reception mode and the regeneration mode can be selected by a simple operation by the control unit, and power saving can be achieved.

  As mentioned above, although the non-contact power receiving apparatus which concerns on this invention was demonstrated based on embodiment, this invention is not limited to this embodiment. Unless it deviates from the meaning of this invention, what made the various deformation | transformation which those skilled in the art conceivable to this Embodiment is also contained in the scope of the present invention.

  For example, in Embodiments 1 and 2, a switching transistor is used as a constituent element of the switching unit. However, any element that can be turned on and off by a control signal may be used. For example, a three-terminal FET or a four-terminal photoMOS relay It may be.

  INDUSTRIAL APPLICABILITY The present invention can be used for a non-contact power receiving device mounted on an automated guided vehicle for transferring a load, and is particularly used in a clean room for a semiconductor process or a flat panel display process that requires a large number of processes and a high degree of dustlessness. It can be used for a non-contact power receiving device mounted on a transport vehicle.

1, 2, 800 Non-contact power receiving device 11, 801 Pickup core 12, 14, 802, 803, 806 Capacitor 13, 23 Switching unit 15, 807 Load 16, 26 Control unit 131, 132B, 133, 134B, 231B, 232B, 233B, 234B Diode 132A, 134A, 231A, 232A, 233A, 234A Switching transistor 700 Non-contact power supply device 710 Non-contact power supply circuit 720 Non-contact power supply line 730 Power supply line holder 804 Reactor 805 Rectifier circuit 810 Core 820 Pickup coil 900 Running rail

Claims (2)

A non-contact power receiving device that receives power from a power feeding device via a power feeding line in a non-contact manner,
A pickup core that receives AC power from the power supply line by electromagnetic induction caused by AC current flowing through the power supply line;
A single switching unit that rectifies AC power received from the power supply line and performs chopper control to generate a predetermined DC voltage and supply the load to a load ;
The switching unit is
It is a single-phase bridge circuit composed of four diode elements,
Of the four diode elements, each of the two diode elements is connected in parallel with a semiconductor switch element for short-circuiting the terminals of the diode elements,
The non-contact power receiving device further includes a control unit that controls conduction and non-conduction of the two semiconductor switch elements,
The control unit rectifies the AC power received from the power supply line to the switching unit by making both of the semiconductor switch elements simultaneously conductive or non-conductive in synchronization with the AC power received from the power supply line. And a non-contact power receiving apparatus that supplies a predetermined voltage to a load by adjusting a ratio between the simultaneous conduction period and the simultaneous non-conduction period . A non-contact power receiving device that receives power from a power feeding device via a power feeding line in a non-contact manner,
A pickup core that receives AC power from the power supply line by electromagnetic induction caused by AC current flowing through the power supply line;
A single switching unit that rectifies AC power received from the power supply line and performs chopper control to generate a predetermined DC voltage and supply the load to a load;
The switching unit is
It is a single-phase bridge circuit composed of four diode elements,
Each of the four diode elements is connected in parallel with a semiconductor switch element for short-circuiting between the terminals of the diode element.
The non-contact power receiving device further includes a control unit that controls conduction and non-conduction of the four semiconductor switch elements,
The control unit is configured to simultaneously or simultaneously turn off two semiconductor switch elements of the four semiconductor switch elements in synchronization with AC power received from the power supply line. By exclusively making the remaining two semiconductor switch elements conductive or non-conductive exclusively, the switching unit rectifies the AC power received from the power supply line , and the AC current received from the power supply line or the Adjusting the timing at which the four semiconductor switch elements are made non-conductive so that the phase relationship between the voltage across the pickup core and the virtual sine wave generated by turning on and off the four semiconductor switch elements is within a predetermined range. Accordingly, the regenerative mode returning electric power corresponding to the regenerative current receiving mode and in the power supply device for supplying a predetermined voltage to a load Non-contact power receiving apparatus select and de.

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