JPH0763201B2 - Power supply device for linear motor - Google Patents

Description

The present invention relates to a power supply device for a linear motor, and more particularly to a power supply device for a linear motor suitable for use in a drive system of a magnetic levitation railway.

A superconducting magnet is mounted as a field pole on the vehicle that is a moving body,
Various types of drive devices for so-called terrestrial primary type linear motors in which propulsion coils are installed on orbits have been proposed so far. FIG. 1 shows one conventional example (Patent No. 231081).
No. 2). That is, the propulsion coil C on the track is connected to the vehicle T.
It is divided into linear motor units LM1, LM2, ... which are longer than the RAIN length, and each linear motor unit is divided into feeder division switches S1, S2 ,.
It is a simplified circuit configuration diagram of a linear motor power supply device that is alternately connected to feeders FA and FB via ..., and is fed by power converters (eg, cycloconverter, inverter, etc.) PCA, PCB connected to the respective feeders. is there.

Hereinafter, the linear motor units LM1, LM3, ... Powered by the power converter PCA are referred to as the A system linear motor unit group, and the linear motor units LM2, LM4 powered by the power converter PCB.
... will be referred to as a B system linear motor unit group. The description of this operation is omitted because it is described in the specification of the above-mentioned patent, but the technical problems so far of this type of linear motor drive device are mainly to reduce the power supply equipment capacity on the ground side, To solve the problems such as the reduction of the thrust fluctuation when the vehicle crosses and the fluctuation of the power on the power receiving side of the power converter, and the switching of the electricity distribution switch in the non-current state when connecting the linear motor unit and the power converter. In practical use,
Of course, it is important to solve these problems, but even if a part of the linear motor driving device including the power converter, the feeder division switch, and the linear motor unit fails,
There is a strong demand for a drive system that can continue to drive the vehicle.

Here, in the power feeding device as shown in FIG. 1, for example, if the power converter PCA fails, power cannot be fed to the linear motor units LM1, LM3 ,. In the section of, the vehicle will be in a coasting state (thrust cannot be obtained). That is, B
LM2, LM4, ... of the system linear motor unit group can obtain intermittent thrust by the linear motor units, but the riding comfort becomes extremely poor.

An object of the present invention is to solve the above-mentioned problems and to provide a power supply device for a linear motor that improves the traveling reliability of the linear motor vehicle.

The present invention appropriately connects and connects a large number of propulsion coils arranged in a row along a track so that a plurality of (split numbers) groups of linear motors are present under the vehicle.
The different linear motor groups are characterized in that they are fed from different power converters.

Hereinafter, the present invention will be described in detail based on specific examples.

FIG. 2A shows an embodiment of the present invention, in which there are two linear motor groups, and the length of each linear motor unit (excitation section) is set to be larger than the vehicle length, a simplified connection of the power supply device. It is a figure.

1st group linear motor unit LMX1, LMX2, LMX3, ...
And the linear motor units of the second group LMY1, LMY2, LMY3,
The thrust coils in …… consist of C1 to Cm + 1 respectively,
As shown in FIG. 3, the propulsion coils of the LMX group and the LMY group are alternately arranged and are connected in series for each group. That is, in FIG. 3, three phases (U
Phase, V phase and W phase) propulsion coils C1 (CU1, CV1, CW1), C2
(CU2, CV2, CW2), C3 (CU3, CV3, CW3), ... Cm + 1 (CUm
+ 1, CVm + 1, CWm + 1) are arranged in a row, and odd-numbered coil C
1, C3, C5, ... Cm are connected in series for each phase to configure one linear motor unit LMX1 of the first group for each predetermined section length, and the power converter is provided via the feeder division switch SX1. Connected to PCAX. On the other hand, even-numbered coils C2, C4, ... Cm + 1
Are connected in series in the same manner to form one linear motor unit LMY1 of the second group, which is connected to the power converter PCAY via the feeder section switch SY1. That is, adjacent propulsion coils are connected to different power converters. The symbols LMNX and LMNY in the figure are neutral points during star connection. Here, in FIG. 3, every other one (2 to 1 interlace) is connected in series like C1, C3, C5, ..., so there can be two linear motor groups, but these are C1, C
4, C7 (not shown), ... Every other two groups (3: 1 interlace) can be connected to form three groups.
Every N-1 (integer of N: 2 or more) (N to 1 interlace), N groups are formed. In the following embodiments, in order to simplify the circuit diagram, the linear motor unit is in the case of 2-to-1 interlace and is represented by a block.

Now, in Fig. 2A, the linear motor unit LMX of the first group
1, LMX2, LMX3, ... Alternately belong to the linear motor unit group of group A and group B, and these are respectively feeder division switches SX1, SX2, SX.
Connected alternately and sequentially to the feeders FAX and FBX that supply electric power to the respective linear motor unit groups via 3, ..., These feeders are connected to the power converters PCAX and PCBX of the first group, respectively. . The linear motor unit of the 2nd group is also the same as the 1st group, and it is feder FAY and FBY through feeder division switches SY1, SY2, SY3, ....
, And these feeders are connected to power converters PCAY and PCBY, respectively.

The basic operation of the linear motor drive device of FIG. 2A having the above-mentioned configuration will be described with reference to the operation chart of FIG. 4A.

When the vehicle TRAIN is in the position shown in FIG. 2A, the feeder division switches SX1, SY1 are closed. Fig. 4A Power distribution switch SX
1, "SY4" means that the switch is in the "closed" state, and "Low" level means that the switch is in the "open" state. Linear motor unit LM under the vehicle
X1 and LMY1 are the power converters PCAX and
Excited by each PCAY, the vehicle is running. In Figure 4A, the operating waveforms of the power converters PCAX, PCBX, PCAY, and PCBY are "high".
The level means “starting state” (the state where the linear motor is energized), and the “low” level means “stopping state”. The sign of the linear motor unit entered at the starting state is It represents the linear motor unit to which the power is supplied. The feeder section switches SX2 and SY2 of the linear motor units LMX2 and LMY2 in front of which the vehicle will enter next are already closed and the power converters PCBX and PCBY connected to them.
Has stopped. Vehicle is a linear motor unit LMX2 and LMY2
Just before, the power converters PCBX and PCBY that were waiting
The power supply starts energizing the linear motor units LMX2 and LMY2 via the feeder division switches SX2 and SY2, respectively (at the time point in FIG. 4A). Then, the vehicle smoothly starts to enter the new linear motor unit with the connected thrust, and when the approach is completed, the energization to the linear motor units LMX1 and LMY1 that do not require excitation is stopped (at the time point in Fig. 4A). Then, open the feeder division switches connected to these linear motor units in a non-current state and close the feeder division switches SX3 and SY3 of the preceding linear motor units LMX3 and LMY3 to close the next. Prepare for excitation (at the point in Figure 4A). Thereafter, in the same manner, the electric power converter is energized to drive the vehicle in units of linear motors in which the vehicle is present while switching the power distribution switches according to the progress of the vehicle.

The operation when the linear motor drive device is normal is as described above, but when some device such as the power converter fails, the operation is as follows.

First, one group of power converter PCAX or P
Consider a case where two units, CAX and PCBX, have failed. At this time, open the switches SLAX and SLBX as shown by the dotted line in the figure,
Disconnect the failed first group of power converters from the feeder. Then, the normal second group is operated as described above. Then, the linear motor unit LMY of the second group
Since 1, LMY2, ... are excited in the same way as during normal operation, the maximum thrust of the vehicle is halved, but the thrust does not become intermittent as in the case of the conventional example in Fig. 1, but rather continuous thrust is applied. It is possible to drive both cars without deteriorating the comfort. Also,
For PCAX and PCBY failures, the remaining power converters PCBX, PCA
You can do the same with Y.

On the other hand, even if there is a short circuit of the feeder, an accident such as a ground fault or a wire break, a failure such as a closing or opening failure of the feeder division switch, and a failure such as a short circuit of the propulsion coil, a ground fault or a wire break, the failure is one group. In that case, continuous driving of vehicles is possible in the remaining groups. Assuming that even in the case of emergency operation that is unavoidable even with intermittent thrust operation, if one of the four power converters can be used (even if three systems are out of order), such operation is possible. Needless to say. Further, if the interlace ratio at the time of connecting the propulsion coil is increased, the configuration becomes complicated, but it is natural that the traveling reliability is further improved.

As described above, according to the present invention, there is an effect that the traveling reliability is significantly improved.

Further, the power supply device according to the present embodiment has a high degree of freedom in system hardware design as described below, and is advantageous in that it can be optimally designed for a large capacity linear motor drive device such as a magnetic levitation railway. There is. That is, the energizing current of the linear motor unit in FIG. 3 is I, the induced voltage of the propulsion coil is E,
When the reactance is X and the resistance is R, the terminal voltage V is as follows.

By the way, in the case of the conventional example of FIG. 1, since the propulsion coils are connected in series without spreading, the number of series is twice that of FIG. 3 (when the lengths of both linear motor units are the same). Therefore, each of E, R, and X is doubled, and the terminal voltage is also doubled.
This means that if the withstand voltage of the propulsion coil is the same, the number of windings of the propulsion coil of FIG. 3 is increased to increase the induced voltage E (reactance also increases) so that the excitation is performed with the same terminal voltage, and the energization current is reduced accordingly. (Motor electric output ∝E
This means that xI can be made equal). In the examination with the same current density of the propulsion coils, the number of turns of the propulsion coils should be doubled in order to make the linear motor unit of FIG. 3 the same as the terminal voltage of FIG.
It becomes 1/2. This has a great advantage in hardware manufacture because the wires of the propulsion coil and the feeder can be made thin. Especially in a large capacity linear motor, there is a limit to increase the terminal voltage from the standpoint of insulation, and the energizing current is on the order of several thousand (A). Therefore, the energizing current is designed to be small as in this embodiment. The advantage of being able to do is great.

FIG. 2B is another embodiment of the present invention. The difference from FIG. 2A is that the linear motor units LMX1, LMX2, LMX of the first group
3, ... for the second group linear motor unit LMY1, L
As shown in the figure, MY2, LMY3, ... are offset by more than the vehicle length (half the linear motor unit length in the figure). The way to connect the linear motor unit, feeder switch, feeder and power converter is the same as in Fig. 2A.

The operation of the power supply device for the linear motor of FIG. 2B will be described using the operation chart of FIG. 4B. When the vehicle is in the position shown, the linear motor units LMX1 and LMY1 under the vehicle are excited by power converters PCAX and PCAY, respectively. Feeding section switch SX of linear motor unit LMX2 where the vehicle enters next
2 is closed and the power converter PCBX is in a stopped state.
Immediately before the vehicle enters and enters the linear motor unit LMX2 (time point in FIG. 4B), the power converter PCBX is activated to start excitation of the linear motor unit LMX2. When the vehicle further advances and exits the linear motor unit LMX1, the power converter PCAX is de-energized (at the time point in FIG. 4B). After that, a currentless state can be established, and the switch SX1 for switching the electric division is opened and the switch SX3 on the front side is closed to stand by (at the time point in FIG. 4B). As the vehicle progresses further, the second group linear motor unit LMY2
The power converter PCBY is activated immediately before entering into and the excitation of LMY2 is started (at the time point in Fig. 4B). And the vehicle is LMY1
After exiting, the power converter PCAY is stopped (time point in FIG. 4B), the switch SY1 is opened and the front switch SY3 is closed in a non-current state (time point in FIG. 4B). Thereafter, in the same manner, the linear motor unit in which the vehicle is present is excited and the vehicle is driven while switching the feeder division switches of each group according to the progress of the vehicle. Here, as seen in the operation waveforms of the power converter in FIG. 4B, the operation states of the power converters PCAX and PCBX of the first group and the operation states of the second group
The operating states of PCAY and PCBY are shifted by the linear motor unit shift in both groups, so the total PS of the apparent power on the power supply side of the four power converters (correctly 4
Should combine the electric power of the power converter
(Simplified as a scalar sum)
It is as small as about half of the fluctuation (PS in FIG. 4A) in the case of the embodiment in the figure. As described above, according to the embodiment of FIG. 2B, in addition to the effect of the embodiment of FIG. 2A, there is an effect of reducing the power fluctuation on the power source side of the power converter. Note that FIG. 5 shows an example of connection of the transformers on the AC power source side of the power converter, and the power receiving transformers TRX and TRY of the first group and the second group are provided separately. This has the advantage that the thermal capacity of the power receiving transformer can be slightly reduced.

FIG. 6 shows another embodiment of the present invention. 2A, the switches between the feeders FAX and FBX to which the first linear motor group is connected and the feeders FAY and FBY to which the second linear motor group is connected, respectively.
There are SPA and SPB. Figure 6 shows the feeder for the return trip.
FNX and FNY, and neutral line crossovers N1 and N2 between the linear motor groups are shown, but these are not always necessary. Hereinafter, the operation and effect of FIG. 6 will be described.

In FIG. 6, the switches SPA and SPB are normally opened,
The output side switches SLAX, SLBX and SLAY, SLBY of the power converter are closed and operate in the same manner as in the case of FIG. 2A. On the other hand, the first
When the group of power converters PCAX, PCBX fails, the output side switches SLAX, SLBX are opened and the switches SPA, SPB are closed (state of FIG. 6). In such a state, feed division switch and power converter PCAY and PC
BY operates similarly to FIG. 2A (FIG. 4A). Then,
The linear motor units of the first group, assuming that the power converter has failed, are connected in parallel with the linear motor units of the second group and are excited by the healthy second group of power converters. Therefore, there is an effect that a smoother thrust can be obtained as compared with the case where only one group is excited.

FIG. 7 shows another embodiment of the present invention, which is different from FIGS. 2B and 6 in that, as will be described below, in the power converters of sound groups, the linear motor units of each group are connected in series. The point is that it is configured to excite. That is, the return side of each output terminal of the power converters PCAX, PCBX, PCAY and PCBY is connected to the return route by the switches SNAX, SNBX, SNAY and SNBY, and the feeders FLAY, F with the same attributes of other groups are connected.
Switch between LBY, FLAX and FLBX respectively SSAY, SSBY,
Configured by connecting with SSAX and SSBX. For the sake of clarity, FIG. 9 shows only a circuit for supplying power to one set of linear motor units LMX1 and LMY1 in FIG. 7 in a three-phase wiring diagram (however, feeder distribution switches SX1 and SY1 are omitted). ). That is, FIG. 9A is a circuit configuration diagram when the power converter PCAX of the first group fails in the normal state, and FIG. 9B is a configuration diagram of the circuit. Normally, the switch SSAX is open, the linear motor unit LMX1 of the first group is excited by the power converter PCAX, and the linear motor unit LMY1 of the second group is excited by the power converter PCAY. On the other hand, when the power converter PCAX of the first group fails, the return side switches SNAX and SNAY of each power converter are opened, and the power converter PSA of the failed group
The switch SLAX on the output side of X is opened and the switch SSAX is closed. Then, normal power converter PCAY, switch SLA
Y, feeder FAY, feeder division switch SY1 (not shown), linear motor units LMY1, LMX1, feeder division switch SX1 (not shown), feeder feeder, stitch SSAX, power converter PCAY power supply circuit is formed. , Linear motor units LMY1 and LMX1 are excited in series by power converter PCAY. Here, in case of failure
In order to excite in series as shown in Fig. 9B and to obtain the advancing force of the same polarity as in Fig. 9A under normal conditions, the propulsion coil of the linear motor unit of one group should be set to the linear motor unit of the other group. It is necessary to note that the winding polarity is reversed, and the power converters of the power converters in that group are also reversed in polarity (normal conditions are the same as abnormal conditions). That is, 9B
Since the series excitation is performed as shown in the figure, the above consideration is required when designing the system.

Next, the operation of FIG. 7 when the vehicle is traveling will be described using the operation chart of FIG. Now the vehicle is a linear motor unit LMX1
And LMY1 exist at the same time, the feeder division switch SX1
And SY1 are closed, and each linear motor unit is a power converter P
It is excited in series by CAY. When the vehicle advances and reaches just before the linear motor unit LMX2 on the front side, the power converter PCBY is activated (at the time point in FIG. 8), and the feeder division switches SX2 and SY2 already closed are met. Excite the linear motor units LMX2 and LMY2 in series. When the vehicle further advances and exits the linear motor unit LMY1, the power converter PCAY that has been supplying power until then is stopped (time point in FIG. 8). After that, the current distribution switch SX1 and SY1 can be opened in the condition of zero current, and the feeding distribution switches SX3 and SY3 of the linear motor units LMX3 and LMY3 on the front side to enter next are closed (at the time point in FIG. 8). Then, when the vehicle arrives just before the linear motor unit LMX3, the power converter PCAY is activated to start the excitation of LMX3 and LMY3 (time point in FIG. 8). Thereafter, in the same manner as above, the vehicle is driven by performing series excitation in units of linear motors in which the vehicle is present while switching the incoming and outgoing switch according to the progress of the vehicle. The following general facts are known from the motion chart of FIG. The feeder division switch of the linear motor unit connected in series of a plurality of linear motor unit groups is opened and closed by the feeder division switch of the linear motor unit on the front side in the traveling direction (SY1, SY2, ... in the example of FIG. 7). ) In synchronization with. Also, a healthy power converter is started immediately before entering the linear motor unit on the rear side in the traveling direction of the linear motor unit connected in series, and stopped at the time when the linear motor unit on the front side is exited, During that time, the linear motor units connected in series are excited.

Now, the linear motor power supply device having the configuration as shown in FIG. 7 and operating as described above has the following advantages in addition to the effects of the embodiment of FIG. First, unlike the case of FIG. 6, since the excitation of each linear motor unit of each group is performed in series when the power converter fails, the same energization is performed without being affected by the imbalance of the induced voltage of each linear motor unit. Therefore, the thrust fluctuation is smaller than that in the case of FIG. 6 (parallel excitation). In particular, if the positions of the linear motor units of each group are displaced as shown in FIG.
There is a problem with parallel excitation in the figure, and series excitation is preferable.
Next, the operational advantages of using this linear motor drive device for a levitation railway will be described. Passenger demand on the railroad is not constant and fluctuates considerably. As a method of coping with this, it is common to adjust the train operation interval or the number of trains of one train. However, in a so-called terrestrial primary type linear motor-driven railway in which a propulsion coil is installed on the track side, it is necessary for one train to correspond to one power conversion device (if one power conversion device corresponds to two or more trains). Therefore, train operation intervals can be shortened only within the range that satisfies this principle. Therefore, a small increase in passenger demand can be dealt with by adjusting train operation intervals, but a large increase in passenger demand can be increased by increasing the number of trains. Therefore, when the demand is low, as a small train, the linear motor unit of each group is series-excited by the power converter of one group and the power converter of the other group fails as a standby system in the circuit configuration as shown in FIG. Be prepared for maintenance and maintenance. On the other hand, when the demand is high, the train is a large train, and therefore the induced voltage in the linear motor unit increases. Therefore, the linear motor unit in each group is excited by the power converter in each group.
That is, in FIG. 7, switches SSAX, SSBX, SSAY, SSBY are open, switches SNAY, SNBY, SNAY, SNBY are open, and switches SLA are.
X, SLBX, SLAY, SLBY are closed. Then, the operation of the feeder division switch and the electric surface converter is performed in the same manner as in FIG. 4B. Therefore, it is possible to cope with a large fluctuation in passenger demand and to efficiently supply electric power. When a failure of the power converter occurs in such a state, as described in the embodiment of FIG. 2, the thrust is reduced but the remaining healthy group can be operated. Also, if you reduce the running speed of the train,
In the state of each switch as shown in FIG. 7, it is possible to perform series excitation in units of linear motors.

As described above, according to the present invention, even if some power converters or the like fail, the vehicle can travel with continuous thrust without impairing the riding comfort, which is an effect of dramatically improving the reliability of vehicle travel. is there.

[Brief description of drawings]

FIG. 1 is a block diagram of a conventional linear motor power supply device,
2A and 2B are wiring diagrams showing the configuration of an embodiment of the present invention,
FIG. 3 is a diagram showing the arrangement and wiring of the propulsion coils in units of linear motors, FIGS. 4A and 4B are the operation charts of FIGS. 2A and 2B, and FIG. 5 is the power converter of FIG. 6 and 7 are wiring diagrams showing the constitution of another embodiment of the present invention, FIG. 8 is an operation chart of FIG. 7, and FIGS. 9A and 9B are respectively. It is a figure which shows the more detailed circuit structure at the time of a power converter normal and failure in the Example of FIG. C1, C2, C3, ... Propulsion coil, LMX1, LMX2, ..., ... Group 1 linear motor unit, LMY1, LMY2, ..., Group 2 linear motor unit, SX1, SX2, ... … 、… First
Group feed switch (opening / closing means), SY1, SY2, ...
..., ... Feeder classification switch (opening / closing means) of the second group,
PCAX, PCBX ... 1st group power converter, PCAY, PCBY ... 2nd group power converter, SLAX, SLBX, SLAY, SLBY ... Switch (third opening / closing means), SPA, SPB ... Switch (2nd switch) Opening / closing means), SSAX, SSBX, SSAY, SSBY ... Switch (fourth opening / closing means), SNAX, SNBX, SNAY, SSBY ... Switch (third opening / closing means), TRAIN ... vehicle (moving body), SCM ... on the vehicle Field pole.

Claims (6)

[Claims] 1. A power supply device for a linear motor, comprising a first linear motor unit in which a plurality of propulsion coils are connected in series and arranged in a line in a track to drive a moving body, and the propulsion constituting the first linear motor unit. A coil is arranged at intervals, and a propulsion coil of a second linear motor unit composed of a plurality of propulsion coils connected in series is arranged between the coils, and a power converter for exciting each of the linear motor units is provided. Equipped with a linear motor power supply device. 2. A power supply device for a linear motor that drives a moving body by exciting a large number of propulsion coils arranged along an orbit with a power converter, and serves as a reference among the propulsion coils arranged in a line. First to N-th linear motor units in which a plurality of (N-1) jumping propulsion coils are connected in series counting from the 1st to Nth propulsion coils, and these N
A power supply device for a linear motor, comprising: a power converter provided corresponding to each of the linear motor units. 3. A linear motor unit group, which comprises a plurality of linear motor units in which a plurality of propulsion coils are connected in series, and which is fed by a common power converter. In a power supply device for a linear motor in which these linear motor units are arranged in a track so as to belong to different linear motor unit groups and a moving body is run, each of the plurality of linear motor units is a propulsion coil in the linear motor unit. Of the propulsion coil that is the standard of
~ The first to N-th linear motor units in which a plurality of (N-1) jumping propulsion coils counting from the Nth unit are connected in series, and each of these linear motor unit groups The power supply device for a linear motor, comprising: a common power converter for each of the first to Nth linear motor units in the linear motor unit group. 4. The linear motor according to claim 3, wherein the first to N-th linear motor units are configured to be displaced in the track direction by a length equal to or more than the length of the moving body traveling on the track. Power supply device. 5. A linear motor power feeding device for traveling a moving body by exciting a large number of multiphase propulsion coils arranged along an orbit by a power converter. Of these, a first linear motor unit in which a plurality of odd-numbered multiphase propulsion coils are connected in series and a second linear motor unit in which a plurality of even-numbered multiphase propulsion coils are connected in series are provided. Neutral points of the first and second linear motor units are connected to each other, and are arranged so that they are excited to have opposite polarities when a current flows in the same direction, respectively, and power conversion for exciting each of the linear motor units. An output side connection path connecting the output side of the power converter and the linear motor unit, and the neutral point and the return path side of the power converter in each of the linear motor units. A roadside connecting path, means for disconnecting the return side connecting path of one linear motor unit of these linear motor units, means for disconnecting the output side connecting path of the other linear motor unit, and this one linear motor unit A power supply device for a linear motor, comprising: a power converter side from a disconnection point of the return side connection path of the above and a serial connection unit that connects the linear motor unit side from a disconnection point of the output side connection path of the other linear motor unit. 6. A linear motor unit group, which comprises a plurality of linear motor units in which a plurality of propulsion coils are connected in series, and which is fed by a common power converter. In a power supply device for a linear motor in which these linear motor units are arranged in a track so as to belong to different linear motor unit groups, and a moving body is run, each of the plurality of linear motor units is arranged in the multiphase Of the propulsion coils, a first linear motor unit in which a plurality of odd-numbered multiphase propulsion coils are connected in series and a second linear motor unit in which a plurality of even-numbered multiphase propulsion coils are connected in series The neutral points of these linear motor units are connected to each other, and are arranged so that they are excited in opposite polarities when currents are passed in the same direction, For each group of linear motor units, a power converter that excites each linear motor unit, and in each linear motor unit, an output side connection path that connects the output side of the power converter and the linear motor unit, A return path connecting path that connects the neutral point and the return path side of the power converter, a means for disconnecting the return path connecting path of one linear motor unit among these linear motor units, and the other linear motor unit Means for disconnecting the output side connecting path, and a power converter side from the disconnecting point of the return side connecting path of the one linear motor unit, and a linear motor unit side from the disconnecting point of the output side connecting path of the other linear motor unit A power supply device for a linear motor, comprising: