JP2000184625A - Non-contact feeding method for transport cars in transporting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact feeding method for transport cars in a transporting system in which the load change of the voltage of the primary side power supply is reduced to feed transport cars by a non-contact method. SOLUTION: This is a non-contact feeding method for transport cars 2a, 2b in a transporting system 1 in which, with a conductor 5 connected to a power supply 3 structuring the primary side, electric power is fed to transport cars 2a, 2b by a non-contact method via a secondary side pickup coil by using the phenomenon of electromagnetic induction caused by the current flowing in the primary side conductor 5. The reactance of the secondary side resonance circuit of the pickup coils mounted on the transport cars 2a, 2b is made to become inductive and capacitive for each transport car. As a result, the effect of a load for each transport car on the primary side power supply 3 is offset with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact power supply method for a transport vehicle in a transport system, and more particularly to a transport method in which a load variation of a voltage of a primary power supply is reduced to supply a power to the transport vehicle in a non-contact manner. The present invention relates to a non-contact power supply method for a carrier in a system.

[0002]

2. Description of the Related Art Conventionally, it has been required to transport components between processes for manufacturing semiconductors, liquid crystals, etc. without polluting a clean environment. In order to avoid dust generation, a non-contact power supply method is adopted. This non-contact power supply method for a transport vehicle uses a conductor connected to a power source as a primary side and uses a magnetic induction phenomenon from a current flowing through the primary side to use a non-contact power supply via a secondary side pickup coil. It is configured to supply electric power to the carrier.

[0003]

By the way, the conventional non-contact power supply method is intended to efficiently obtain power from the current flowing through the primary conductor, to reduce the size of the device, and to reduce electromagnetic noise. In consideration of the suppression, the upper limit of the frequency is suppressed, and a high frequency current of several kilohertz to several tens of kilohertz is caused to flow from the power supply to the primary conductor. Usually this 1
The secondary conductor is made up of a reciprocating conductor,
By arranging the current returning to the power supply spatially close to each other, the magnetic field generated by the primary current is canceled as much as possible, and the inductance due to the magnetic flux linked to the primary conductor is reduced. However, since high frequency currents are used,
The reactance of the primary conductor is relatively large, and there is a problem that the primary conductor is susceptible to voltage fluctuation due to the load.

On the other hand, a feeder circuit provided in the carrier for receiving power supply in a non-contact manner through a secondary pickup coil is provided with a capacitor in series with the pickup coil in order to compensate for the reactance due to the inductance of the pickup coil. And a load is connected to both ends of this capacitor. Therefore, when X = 0, the combined reactance X of the series circuit composed of the pickup coil and the capacitor corresponds to the so-called series resonance, and the input of the load is reduced by a slight input. Although a large voltage can be applied to the terminal, since the fluctuation of the load terminal voltage when deviating from the equilibrium point is large, it is usually close to the series resonance, but the non-contact power supply is performed when the synthesized reactance X is slightly left. I have. The combined reactance X remaining in the secondary side resonance circuit is converted and added to the primary side, and acts as a reactance. However, in a large-scale transport system, the number of transport vehicles used is increased to several tens, and the combined reactance of the resonance circuit of each pickup coil is converted and added to the primary side. There is a problem that the voltage of the primary side power supply is greatly affected by the load fluctuation.

The present invention has been made in view of the above-mentioned problems of the non-contact power supply method for a transport vehicle in the conventional transport system, and has been made to reduce the load variation of the voltage of the primary power supply so as to supply power to the transport vehicle in a non-contact manner. It is an object of the present invention to provide a non-contact power supply method for a transport vehicle in a transport system that has been provided.

[0006]

In order to achieve the above object, a non-contact power supply method for a transport vehicle in a transport system according to the present invention is directed to a method in which a primary wire is connected to a power supply and a current flowing through the primary conductive wire. In a non-contact power supply method for a carrier in a carrier system for supplying power to the carrier in a non-contact manner through a secondary-side pickup coil by utilizing an electromagnetic induction phenomenon from a secondary coil of the pickup coil mounted on the carrier. The reactance of the side resonance circuit is made inductive and capacitive for each carrier, so that the influence of the load of each carrier on the primary-side power supply is offset each other.

[0007] A non-contact power supply method for a transport vehicle in this transport system includes a pickup coil mounted on the transport vehicle.
Since the reactance of the secondary side resonance circuit is made inductive and capacitive for each carrier, and the influence of the load of each carrier on the primary-side power supply is offset each other, a large number of carriers is required. Even in a large-scale transport system, the voltage drop due to the combined reactance of the secondary-side resonance circuit is canceled out without being converted and added to the primary-side power supply, so that the load fluctuation of the voltage of the primary-side power supply is greatly reduced. be able to.

In this case, it is possible to alternately arrange the transport vehicle in which the reactance of the secondary resonance circuit of the pickup coil is inductive and the transport vehicle in which the reactance is capacitive.

As a result, the load fluctuation of the voltage of the primary power supply can be efficiently reduced over the entire length of the primary conductor.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a non-contact power supply method for a transport vehicle in a transport system according to the present invention will be described with reference to the drawings.

1 to 3 show one embodiment of a non-contact power supply method for a transport vehicle in a transport system according to the present invention. The transport system 1 includes a primary conductor 5 for supplying power to the transport vehicle in a non-contact manner along a transport route of the transport vehicle, and a primary power source 3 connected to the conductor 5. In addition, a plurality of transport vehicles 2a and 2b are arranged so as to be able to travel along the transport path.

As shown in FIG. 2, the conductor 5 on the primary side is made up of reciprocating conductors 5a and 5b, and includes a conductor 5a for passing a current from the power source 3 and a conductor 5b for passing a current returning to the power source. They are arranged close to each other in space, so that the magnetic field generated by the primary current is canceled as much as possible, and the inductance due to the magnetic flux interlinking with the conductor 5 on the primary side is reduced.

From the current flowing in the primary conductor 5, the electromagnetic induction phenomenon is used to cause the vehicles 2 a and 2 b to pass through the secondary pickup coil 12 wound around the iron core 13 of the pickup 11. Electric power is obtained without contact. Carriers 2a and 2b, which receive power from the primary conductor 5 in a non-contact manner via the pickup coil 12, contact the secondary resonance circuit provided for each carrier with the reactance of the carrier 2a, for example.
Is inductive, while on the other hand, the carrier 2b is capacitive.

FIG. 3 shows a resonance circuit for effectively taking power from the current flowing through the primary conductor 5 by the secondary pickup coil 12 under the mutual inductance M by utilizing the electromagnetic induction phenomenon. as shown, in order to compensate for the reactance due to the inductance L ₂ of the pick-up coil 12, the load from both ends of the capacitor 4 which is adapted to connect to a series, i.e., the transport vehicle 2a or transport vehicle 2
b.

The combined reactance X of the series circuit composed of the pickup coil 12 and the capacitor 4 can be expressed as follows: X = ωL ₂ −1 / (ωC ₂ ) (1) In the above, the combined reactance X of the series circuit is X = 0, which corresponds to so-called series resonance. At this time, a large voltage can be applied to the load terminal with a small input. However, since the fluctuation of the load terminal voltage when deviating from the equilibrium point is large, it is usually close to the series resonance, but the synthesized reactance X slightly remains. By the way, non-contact power supply is performed.

In this case, the synthetic reactance X is made inductive,
That is, it is easy to realize a positive value and a capacitive value, that is, a negative value. In a transport system having a plurality of transport vehicles 2a and 2b on which a non-contact power supply device is mounted, a large number of non-contact power supply devices are connected to a primary current having the same frequency characteristic. No means for changing the angular frequency ω of the pickup coil 12 is used, and the inductance L ₂ of the pickup coil 12 and the series capacitor 4
By changing the combination of the capacitance C _2, non-contact power feeding device can be easily realized with an inductive secondary reactance and capacitive secondary reactance.

Next, the effect of the combined reactance X of the secondary side resonance circuit on the primary side power supply 3 will be described. For the sake of simplicity, it is assumed that the primary and secondary resistance components are ignored, and the case where there is no load connected to both ends of the series capacitor 4 is dealt with. There are few essential differences in the basic mechanism from when they are considered.

Under the above conditions, the following simultaneous equations (2) and (3) of the AC circuit are established in the circuit shown in FIG. V ₁ = jωL ₁ I ₁ + jωMI ₂ (2) jωMI ₁ + jXI ₂ = 0 (3) where X is connected in series to the secondary-side pickup coil 12. This is a combined reactance of a series resonance circuit including the capacitor 4.

Equation (4) is obtained from the simultaneous equations (2) and (3). V ₁ = jωL ₁ I ₁ −j (ω ² M ² / X) I ₁ (4)

In the equation (4), V ₁ indicates a terminal voltage of the primary power source 3 required when a current of I ₁ flows through the primary conductor 5. The first term on the right side of the equation (4) is a voltage drop caused by a reactance caused by the inductance L ₁ of the primary conductor 5. The second term on the right side of the equation (4) is a voltage at which a current I ₂ flowing through a series resonance circuit including the secondary pickup coil 12 and the capacitor 4 connected in series thereto is induced to the primary conductor 5. . The sign of the second term on the right side of Expression (4) is the opposite sign of the sign of the combined reactance X of the secondary-side series resonance circuit.

Therefore, as in this embodiment, the transport vehicle 2
a, 2b so that the reactance of the secondary side resonance circuit of the pickup coil is inductive and capacitive for each carrier 2a, 2b, more preferably the inductive carrier 2a, And the transfer vehicles 2b are alternately disposed, the voltage drops due to the combined reactance of the secondary side resonance circuit are canceled out without being converted and added to the primary side power supply. Load fluctuation of the voltage of the side power supply can be greatly reduced.

[0022]

According to the non-contact power supply method for a carrier in the carrier system, the reactance of the secondary resonance circuit of the pickup coil mounted on the carrier is made inductive and capacitive for each carrier. Since the influence of the load of each carrier on the secondary power supply is offset each other, even in a large-scale transport system including a large number of transport vehicles, the voltage drop due to the combined reactance of the secondary resonance circuit is reduced by the primary power supply. Are offset by each other without being converted to
The load fluctuation of the voltage of the secondary power supply can be greatly reduced, and as a result, an expensive control device for suppressing the load fluctuation is not required. Power can be supplied by contact.

Further, the carrier is connected to the pickup coil 2.
A transport vehicle in which the reactance of the secondary resonance circuit is inductive,
By alternately arranging capacitive vehicles, the load fluctuation of the voltage of the primary power supply can be efficiently reduced over the entire length of the primary conductor.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a transport system to which a non-contact power supply method for a transport vehicle in a transport system of the present invention is applied.

FIG. 2 is a cross-sectional view showing a positional relationship between a primary conductor and a pickup coil.

FIG. 3 is a circuit diagram to which a non-contact power supply method for a carrier in the carrier system of the present invention is applied.

[Explanation of symbols]

1 transport system 2a synthetic reactance transport vehicle transport vehicle 2b synthetic reactance is inductive is a capacitive 3 primary side power supply 4 capacitor 5 primary conductor 5a conductor 5b conductor 12 picks Abbu coil 13 core V ₁ primary power supply Terminal voltage I ₁ Current of primary side conductor M Mutual inductance between primary side conductor and secondary side pickup coil L ₂ Inductance of pickup coil C ₂ Capacitance of capacitor I ₂ Current of secondary side series resonance circuit

Claims (2)

[Claims] 1. A conductor connected to a power supply is used as a primary side.
Using the electromagnetic induction phenomenon from the current flowing in the primary conductor,
In a non-contact power supply method for a carrier in a carrier system for supplying power to a carrier in a non-contact manner via a secondary pickup coil, a reactance of a secondary resonance circuit of a pickup coil mounted on the carrier is determined for each carrier. A non-contact power supply method for a transport vehicle in a transport system, wherein the inductive and capacitive characteristics of the transport system cancel each other out of the influence of the load of each transport vehicle on the primary-side power supply. 2. The carrier according to claim 1, wherein the carrier having the inductive reactance of the secondary resonance circuit of the pickup coil and the carrier having the capacitive reactance are alternately arranged. Item 2. A non-contact power supply method for a carrier in the carrier system according to Item 1.