JP7262262B2 - Winding switching device for rotating electrical machine, rotating electrical machine drive system, and electric equipment - Google Patents

Description

The present invention relates to a winding switching device for switching the connection state of a rotating electrical machine, a rotating electrical machine driving system including the winding switching device, and an electric machine driven by the rotating electrical machine driving system including the winding switching device.

2. Description of the Related Art Techniques for switching the connection state of windings are known in order to differentiate the output characteristics of an electric motor, which is a rotating electrical machine, between high-speed and low-speed ranges.

For example, the winding switching device described in Patent Document 1 includes a device main body including a plurality of electrodes to which ends of a plurality of windings are connected, a series connection circuit section and a parallel connection circuit section arranged in the switching direction. and a driving device that operates the movable body in the switching direction. When the movable body is driven by the driving device and the electrodes of the device main body come into contact with the electrodes of the series connection circuit section and the electrodes of the parallel connection circuit section movable body of the movable body, the windings of the motor are brought into a series state and a parallel state, respectively. connected to the state.

JP 2017-70112 A

Here, in a rotating electric machine drive system in which a mechanical load is driven at a variable speed by an electric motor, when a power supply source (for example, an inverter) to the electric motor stops, the electric motor rotates due to the inertia of the mechanical load and operates as a generator. Therefore, a circuit breaker is provided to open the windings of the motor to protect the drive system. In such a rotary electric machine drive system, if the winding switching device according to the conventional technology is provided, there is a problem that the rotary electric machine drive system becomes large.

Accordingly, the present invention provides a winding switching device capable of suppressing an increase in the size of a drive system while enabling switching of the connection state of the windings of a rotating electrical machine, a rotating electrical machine drive system including the winding switching device, and a winding switch. An electric machine driven by a rotating electric machine drive system having a switching device is provided.

In order to solve the above problems, a winding switching device according to the present invention switches between parallel connection and series connection of a plurality of windings of a rotating electric machine, and includes a plurality of electrodes connected to a plurality of windings and a power source. a movable portion that contacts the plurality of electrodes and includes a plurality of conductors; and an actuator that drives the movable portion, wherein the first The plurality of windings are connected in parallel at the stop position of , the plurality of windings are opened at the second stop position of the movable portion, and the plurality of windings are connected in series at the third stop position of the movable portion. , and further includes any one of the following first to third means .
In the first means, the plurality of electrodes includes a first electrode connected to the winding start of the winding and connected to a power source, and a second electrode connected to the winding end of the winding. , the distance between the end of the first electrode and the end of the second electrode is greater than the width of the conductor portion, and in the second stop position, the conductor portion extends between the first electrode and the second electrode. and is not in contact with the first electrode and the second electrode.
In the second means, the plurality of electrodes includes a first electrode connected to a first phase winding of the rotating electric machine among the plurality of windings, and a second electrode of the rotating electric machine among the plurality of windings. and a second electrode to which the winding for the phase is connected, the first electrode and the second electrode being adjacent to each other and forming a neutral point.
In a third means, the outer shape is cylindrical.

In order to solve the above-described problems, a rotating electrical machine drive system according to the present invention includes a rotating electrical machine and an inverter that supplies alternating current power to the rotating electrical machine, wherein a winding switching device includes a winding according to the present invention. It is a switching device.

In order to solve the above problems, an electric machine according to the present invention is operated at variable speeds by a rotating electrical machine drive system, and the rotating electrical machine drive system is the rotating electrical machine drive system according to the present invention.

According to the present invention, since the winding switching device can open the windings, it is possible to eliminate the need for a circuit breaker for opening the windings of the motor.

Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is a configuration diagram of a winding switching device that is Embodiment 1. FIG. 1 is a circuit diagram of a rotary electric machine drive system that is an embodiment; FIG. FIG. 3 is a circuit diagram showing a connection state of three-phase windings of a three-phase AC motor in the embodiment; It is a figure which shows an example of the relationship between the rotation speed of an electric motor, and an electric motor (motor) efficiency. FIG. 5 is a diagram showing an example of current waveforms when the same rectangular wave voltage is applied to parallel-connected and series-connected windings. 4 is a configuration diagram of a winding switching device that is a comparative example with respect to the first embodiment; FIG. FIG. 10 is a configuration diagram of a winding switching device that is Embodiment 2; FIG. 11 is a configuration diagram of a winding switching device that is Embodiment 3; 1 is a configuration diagram of an electric railway vehicle that is an embodiment; FIG.

First, a rotating electrical machine drive system that is an embodiment of the present invention will be described with reference to FIGS. 2-5.

FIG. 2 is a circuit diagram of a rotating electrical machine drive system that is an embodiment of the present invention.

In rotary electric machine drive system 1 , three-phase AC motor 2 is driven by AC power from an inverter main circuit that converts DC power into AC power by semiconductor switching elements 5 . As the three-phase AC motor 2, for example, a permanent magnet synchronous motor is applied.

The inverter main circuit has a three-phase full bridge circuit consisting of six semiconductor switching elements 5 and freewheeling diodes 7 connected in anti-parallel to each of the six semiconductor switching elements 5 . In this embodiment, a three-phase full bridge circuit is configured by connecting three power modules 6 in parallel. In one power module 6, two arms each composed of a set of semiconductor switching elements 5 and freewheeling diodes 7 are connected in series.

A capacitor 4 is connected to the DC input side of the three-phase full bridge circuit. A capacitor 4 smoothes the input voltage from the DC power supply 3 . DC power supplied from a DC power supply 3 is smoothed in voltage by a capacitor 4 and input to a three-phase full bridge circuit.

Semiconductor switching element 5 is ON/OFF-controlled by a gate control signal output from control device 10 in FIG. , are output from the AC output terminals (U, V, W). In addition, in this embodiment, the serial connection point of the two arms in the power module 6 serves as an AC output terminal. A three-phase AC motor 2 is driven by the three-phase AC power output from the inverter main circuit.

A control device 10 in FIG. 2 creates a gate control signal according to a control command from a higher control device (not shown). Therefore, by using the speed command as the control command, the three-phase AC motor 2 is driven at a variable speed.

As shown in FIG. 2, between the AC output terminals (U, V, W) of the inverter main circuit and the three-phase winding terminal group 21 of the three-phase AC motor 2, the three-phase windings are connected. A switching winding switching device 9 is connected. The winding switching device 9 switches the connection state of the three-phase windings according to a winding switching command from the control device 10 . The control device 10 connects the windings in series when the speed is in the low speed range, and connects the windings in parallel when the speed is in the high speed range, as will be described later, according to the speed of the three-phase AC motor 2 . Connect. Note that the control device 10 determines whether the speed of the three-phase AC motor 2 is in a predetermined low speed range or a high speed range based on a control command (speed command) or a speed detection value (or a speed estimation value). Then, a winding switching command is created according to the determination result.

In addition to the function of switching the connection state of the windings as described above, the winding switching device 9 in the present embodiment has a function of opening the three-phase windings of the three-phase AC motor 2, that is, switching between the three-phase windings and the inverter main. It has the function of breaking the electrical connection with the circuit. As a result, when the inverter main circuit stops operating due to a failure or the like, the three-phase AC motor 2 rotates due to mechanical inertia to operate as a generator, and a large current flows through the three-phase windings and the inverter main circuit. can be prevented. Furthermore, since the winding switching device 9 has the function of opening the three-phase windings, it is not necessary to provide a circuit breaker between the three-phase windings and the inverter main circuit. Also, an increase in the size of the electric motor drive system can be suppressed.

In addition, in the inverter main circuit of FIG. 2, as the capacitor 4, an electrolytic capacitor or a film capacitor can be applied. In order to increase the capacity of the capacitor 4, a plurality of small capacity capacitors may be connected in parallel or in series. In FIG. 2, an IGBT (Insulated Gate Bipolar Transistor) is applied as the semiconductor switching element 5, but the semiconductor switching element 5 is not limited to this, and a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) or the like may be applied. Moreover, the freewheeling diode 7 may be externally attached to the semiconductor switching element or may be incorporated therein. When the semiconductor switching element 5 is a MOSFET, a body diode (parasitic diode) within the element may be used as the freewheeling diode 7 .

FIG. 3 is a circuit diagram showing the connection state of the three-phase windings of the three-phase AC motor 2 in this embodiment.

The three-phase AC motor 2 includes a plurality of (two in FIG. 3) three-phase windings. That is, the three-phase AC motor 2 includes a first three-phase winding composed of a U-phase winding _21U1 , a V-phase winding _21V1 , and a W-phase winding _21W1 , and a U-phase winding _21U2 . and a second three-phase winding composed of a V-phase winding _21V2 and a W-phase winding _21W2 .

The upper diagram of FIG. 3 shows a state of parallel connection of windings, in which each phase winding in the first three-phase winding and each phase winding in the second three-phase winding are connected in parallel. be. For example, for the U phase, the winding start Us1 of U _{-phase winding 21U1 and the winding start Us2 of U -} phase winding 21U2 are connected, and the winding end _Ue1 of U-phase winding _21U1 and U-phase The winding end _Ue2 of the winding _21U2 is connected. As a result, U-phase winding _21U1 and U-phase winding _21U2 are connected in parallel. The U-phase winding of the three-phase AC motor ₂ is configured by the parallel connection of the U-phase winding _21U1 and the U-phase winding 21U2.

As _for the V _- phase and W-phase, as shown in the upper diagram of FIG. The W-phase winding _21W1 and the W-phase winding _21W2 are connected in parallel to form the W-phase winding of the three-phase AC motor 2.

Out of both ends of the U-phase winding, the V-phase winding, and the W-phase winding of the three-phase AC motor 2 configured in this manner, the respective winding end sides are connected to each other to form a neutral point. That is, the U-phase winding, the V-phase winding, and the W-phase winding of the three-phase AC motor 2 are star-connected (Y-connected). In addition, among both ends of the U-phase winding, the V-phase winding, and the W-phase winding of the three-phase AC motor 2, each winding start side is the three-phase AC power source 8 (AC outputs U and V of the inverter main circuit in FIG. 2). , W).

In the figure, similar to the symbols U _si and U _ei (i=1, 2) described _above , V _si and V _ei indicate the winding start and winding end of the V-phase winding 21V _i , respectively. W _ei indicate the winding start and winding end of W-phase winding 21W _i , respectively. In the following, the start and end of winding of each phase winding are indicated by symbols only.

The lower diagram of FIG. 3 shows a series connection of windings, in which each phase winding in the first three-phase winding and each phase winding in the second three-phase winding are connected in series. . For example, for the U-phase, the winding end _Ue1 of the U-phase winding _21U1 and the winding start _Us2 of the U-phase winding _21U2 are connected. As a result, U-phase winding _21U1 and U-phase winding _21U2 are connected in series. The U-phase winding of the three-phase AC motor ₂ is configured by the series connection of the U-phase winding _21U1 and the U-phase winding 21U2.

As _for the V _- phase and W-phase, as shown in the upper diagram of FIG. The W-phase winding _21W1 and the W-phase winding _21W2 are connected in series to form the W-phase winding of the three-phase AC motor 2.

Out of both ends of the U-phase winding, the V-phase winding, and the W-phase winding of the three-phase AC motor 2 configured in this manner, the respective winding end sides are connected to each other to form a neutral point. That is, the U-phase winding, the V-phase winding, and the W-phase winding of the three-phase AC motor 2 are star-connected (Y-connected). In addition, among both ends of the U-phase winding, the V-phase winding, and the W-phase winding of the three-phase AC motor 2, each winding start side is the three-phase AC power source 8 (AC outputs U and V of the inverter main circuit in FIG. 2). , W).

Next, the difference in the characteristics of the motor depending on the connection state of the windings will be described.

Harmonic loss _Wh generated by the rotating electrical machine when the rectangular wave voltage output by the inverter main circuit is supplied to the rotating electrical machine is represented by Equation (2).

Here, K is a proportional coefficient, _Vn is the n-th harmonic component of the rectangular wave voltage, and _In is the n-th harmonic component of the current flowing through the winding. V _n and I _n have the relationship of formula (2).

Here, the impedance _Zn is represented by Equation (3).

Here, R is the resistance of the winding of the rotating electrical machine, L is the inductance of the winding of the rotating electrical machine, and _fn is the frequency of the n-order harmonic component.

Equation (4) is obtained from equations (1), (2) and (3).

Here, since R<<2πjf _n L, the equation (5) is obtained by simplifying the equation (4).

Assuming that each inductance of the two windings whose connection state can be changed is _L0 , the inductance _Ls of the series connection and the inductance _Lp of the parallel connection are expressed by equations (6) and (7), respectively.

If the harmonic losses in parallel connection and _series connection are _Whp and _Whs , respectively, the voltage applied from the inverter main circuit is the same _Vn . By using equations (6) and (7) as _Ls , _Whp and _Whs are represented by equations (8) and (9), respectively.

As shown by equations (8) and (9), the series connection harmonic loss _Whs is smaller than the parallel connection high frequency loss _Whp .

Next, the results of studies conducted by the present inventor on the efficiency of rotating electric machines based on such high-frequency loss will be described.

FIG. 4 is a diagram showing an example of the relationship between the number of revolutions of the electric motor and the efficiency of the electric motor (motor).

As shown in FIG. 4, in the case of parallel windings (parallel connection), the efficiency is low in the low speed range, and the efficiency is high in the high speed range because the output can be increased. On the other hand, in the case of windings in series (series connection), the efficiency is high in the low speed range, but the efficiency is low in the high speed range because the output is small.

FIG. 5 is a diagram showing an example of current waveforms when the same rectangular wave voltage is applied to parallel-connected and series-connected windings. As shown in equations (6) and (7), the winding inductance of the series connection is larger than that of the parallel connection. Therefore, as shown in FIG. less than

Based on the difference in loss caused by the connection state of the windings as described above, the winding switching device allows series connection in the low-speed range of the rotating electrical machine and parallel connection in the high-speed range of the rotating electrical machine. , the rotating electric machine can be operated with high efficiency.

A winding switching device according to an embodiment of the present invention will be described below with reference to Examples 1 to 3 with reference to FIGS. 1 and 6-8. In each figure, the same reference numbers denote the same components or components with similar functions.

FIG. 1 is a configuration diagram of a winding switching device that is Embodiment 1 of the present invention. 1 also shows the operation of the winding switching device. To avoid complication of the drawing, most of the reference numerals indicating the parts of the winding switching device are shown only in the upper drawing of FIG.

As shown in the upper diagram of FIG. 1, the winding switching device 9 of the first embodiment includes phase windings (21U _i , 21V _i , 21W _i : i=1, 2) constituting a plurality of three-phase windings. ) winding start (U _si , V _si , W _si : i=1, 2) and winding end (U _ei , V _ei , _Wei : i=1, 2) are connected to a plurality of electrodes (22 U _si , 22U _ei , 22V _si , 22V _ei , 22W _si , 22W _ei : i=1, 2) and a plurality of conductor portions (32a to 32f) for short-circuiting two adjacent electrodes among these plurality of electrodes. A portion 33 and an actuator 31 that drives the movable portion 33 are provided.

A plurality of electrodes (22U _si , 22U _ei , 22V _si , 22V _ei , 22W _si , 22W _ei : i=1, 2) are separated from each other, the phase windings are not connected, and the movable part 33 is They are electrically insulated from each other when not short-circuited by the conductors (32a-32f). Also, the plurality of electrodes are fixed to a support (not shown). Moreover, the plurality of conductor portions (32a to 32f) in the movable portion 33 are separated from each other, fixed to the support 34, and electrically insulated from each other at the support 34. FIG. In addition, in the first embodiment, the support 34 is made of an insulator (the same applies to other embodiments and comparative examples).

A plurality of electrodes (22U _si , 22U _ei , 22V _si , 22V _ei , 22W _si , 22W _ei : i=1, 2) are arranged side by side in a predetermined direction at intervals. Also, the plurality of conductor portions (32a to 32f) are arranged side by side in the same direction as the direction in which the plurality of electrodes are arranged with a space therebetween. Since the movable portion 33 is in contact with a plurality of electrodes, when the movable portion 33 is slid by the actuator 31 along the direction in which the plurality of electrodes and the conductors are arranged, the plurality of electrodes are short-circuited by the plurality of conductors. Change sequentially. This changes the connection state of the windings of the three-phase AC motor. In the first embodiment, the first position (upper diagram of FIG. 1), the second position (central diagram of FIG. 3 (lower diagram in FIG. 1), the connection state of each phase winding is respectively parallel winding (upper diagram in FIG. 3) and open winding (in FIG. 3, winding and three-phase AC power supply 8 cut off the electrical connection) and windings in series (lower diagram in FIG. 3).

Further detailed configuration and operation of the winding switching device of the first embodiment are as follows.

As shown in the upper diagram of FIG. 1, each phase winding of the first three-phase winding (21U ₁ , 21V ₁ , 21W ₁ ) and the second three-phase winding (21U ₂ , 21V ₂ , 21W ₂ ) 12 electrodes 22U _s1 , 22U s2 , 22U _e1 , 22U _e2 , 22V _s1 , 22V _s2 , 22V _e1 , 22V _e2 , 22W s1 , 22W _{s2 ,} 22W _e1 , 22W _e2 equal to the total number of winding start and _winding end of , in this order, in a predetermined direction, in the first embodiment, in a direction away from the actuator 31 side, with a space therebetween. These electrodes 22U _s1 , 22U _s2 , 22U _e1 , 22U _e2 , 22V _s1 , 22V _s2 , 22V e1 , 22V _e2 , 22W _s1 , 22W _s2 , 22W _e1 , _{22W e2} are connected to U-phase winding 21U ₁ . Winding start U _s1 , winding start U _s2 of U-phase winding 21U ₂ , winding end U _e1 of U-phase winding 21U ₁ , winding end U _e2 of U-phase winding 21U ₂ , winding start of V-phase winding 21V ₁ V _s1 , winding start V _s2 of V-phase winding 21V ₂ , winding end V _e1 of V-phase winding 21V ₁ , winding end V _e2 of V-phase winding 21V ₂ , winding start W _s1 of W-phase winding 21W ₁ , the winding start W _s2 of the W-phase winding 21W ₂ , the winding end W _e1 of the W-phase winding 21W ₁ , and the winding end W _e2 of the W-phase winding 21W ₂ are electrically connected.

Therefore, _{a U-phase winding connection electrode group consisting of electrodes 22U s1 , 22U s2 , 22U e1 and 22U e2 connecting U - phase} windings 21U 1 and 21U ₂ and V-phase windings 21V ₁ and 21V ₂ are connected. V-phase winding connection electrode group consisting of electrodes 22V _s1 , 22V _s2 , 22V _e1 and 22V _e2 , and electrodes 22W _s1 , 22W _s2 , 22W _e1 and 22W _e2 connecting W-phase windings 21W ₁ and 21W ₂ W-phase winding connection electrode groups are arranged in this order in a direction away from the actuator 31 side. Among the electrodes (for example, 22U _s1 and 22U _e2 ) positioned at both ends of each electrode group, the electrode (22U _s1 ) positioned at one end on the side of the actuator 31 is connected to the corresponding one phase (U phase) of the three-phase AC power supply. The connected electrode (22U _e2 ) located at the other end constitutes the neutral point (N) in the star connection of the three-phase winding.

Furthermore, the electrodes 22U _s1 , 22V _s1 , 22W _s1 are electrically connected to the U-phase, V-phase, and W-phase of a three-phase AC power supply (inverter main circuit in FIG. 2), respectively. Furthermore, the electrodes U _e2 , V _e2 , and W _e2 are electrically connected to each other to form the neutral point N of the star connection (Y connection).

Six conductor portions 32a, 32b, 32c, 32d, 32e, and 32f included in the movable portion 33 are arranged in this order with electrodes 22U _s1 , 22U _s2 , 22U _e1 , 22U _e2 , 22V _s1 , 22V _s2 , and 22V _e1 . , 22V _e2 , 22W _s1 , 22W _s2 , 22W _e1 , and 22W e2 are arranged side by side at intervals in the same predetermined direction as the direction in which 22V e2 , 22W s1 , 22W s2 , 22W _e1 , and 22W e2 are arranged.

The movable portion 33 is moved by the actuator 31 along the direction in which the plurality of electrodes (22U _s1 , . . . ) and the conductor portions (32a, . At this time, the stop position of the movable portion 33 is the position shown in the upper diagram of FIG. 1 (first position), the position shown in the middle diagram of FIG. 1 (second position), and the position shown in the lower diagram of FIG. 3 position).

As shown in the upper diagram of FIG. 1, in the first position, the electrodes 22U _s1 and 22U _s2 are shorted by the conductor 32a, and the electrodes 22U _e1 and 22U _e2 are shorted by the conductor 32b. As a result, the winding start _Us1 and the winding end _Ue1 of the U-phase winding 21U1 are electrically connected to _the winding start _Us2 and the winding end _Ue2 of the U-phase winding _21U2 , respectively. That is, U-phase winding _21U1 and U-phase winding _21U2 are connected in parallel.

At the first position, the electrodes 22V _s1 and 22V _s2 are shorted by the conductor 32c, and the electrodes 22V _e1 and 22V _e2 are shorted by the conductor 32d. Thus, the winding start _Vs1 and the winding end Ve1 of the V-phase winding _21V1 are electrically connected to _the winding start _Vs2 and the winding end _Ve2 of the V-phase winding _21V2 , respectively. That is, the V-phase winding _21V1 and the V-phase winding _21V2 are connected in parallel.

Furthermore, in the first position, the electrodes 22W _s1 and 22W _s2 are short-circuited by the conductor portion 32e, and the electrodes 22W _e1 and 22W _e2 are short-circuited by the conductor portion 32f. As a result, the winding start _Ws1 and the winding end _We1 of the W _- phase winding 21W1 are electrically connected to the winding start _Ws2 and the winding end _We2 of the W-phase winding _21W2 , respectively. That is, the W-phase winding _21W1 and the W-phase winding _21W2 are connected in parallel.

As described above, when the movable portion 33 is at the first position, the windings of each phase of the three-phase AC motor are connected in parallel as shown in the upper diagram of FIG.

As shown in the central view of FIG. 1, in the second position, electrodes 22U _s2 and 22U _e2 are in contact with conductor portion 32a and conductor portion 32b, respectively, while electrode 22U _s1 and electrode 22U _e1 are in contact with conductors 32a and 32b, respectively. Although it is adjacent to the portion 32a and the conductor portion 32b, both are not in contact with these conductor portions. At the second position, the electrodes 22U _s1 and 22U _e1 are in contact with only the support 34 among these conductors and the support 34 electrically insulated from these conductors. . The electrode 22U _s1 contacts the support 34 between the conductor portion 32a and the actuator 31, and the electrode 22U _e1 contacts the support 34 between the conductor portion 32a and the conductor portion 32b. This opens the U-phase winding _21U1 and the U-phase winding _21U2 .

Here, in the first embodiment, the distance between the electrode _{22U s1} and the electrode _{22U e1} in the direction in which the plurality of electrodes and the plurality of conductors are arranged. is set to a value larger than the width L ₂ of the conductor portion _32b (the same applies to the other conductor portions) (L ₁ >L ₂ ). As a result, at the second position, the electrode 22U _s1 and the electrode 22U _e1 are brought into the non-contact state as described above, that is, the U-phase winding _21U1 and the U-phase winding _21U2 are open.

Also, as shown in the central view of FIG. 1, in the second position, the electrodes 22V _s2 and 22V _e2 are in contact with the conductor portion 32c and the conductor portion 32d, respectively, while the electrodes 22V _s1 and 22V _e 1 Although they are adjacent to the conductor portions 32c and 32d, respectively, they are not in contact with these conductor portions. In the second position, the electrodes 22V _s1 and 22V _e1 are in contact with only the support 34 among these conductors and the support 34 electrically insulated from these conductors. . Electrode 22V _s1 contacts support 34 between conductor portions 32b and 32c, and electrode 22V _e1 contacts support 34 between conductor portions 32c and 32d. As a result, the V-phase winding _21V1 and the V-phase winding _21V2 are opened.

Here, in the first embodiment, the distance between the electrodes 22V _{s1 and} the electrodes _{22V e1} in the direction in which the plurality of electrodes and the plurality of conductors are arranged. is set to _{a value larger than the width L 2 of} the conductor portion 32d (the same applies to other conductor portions) (L ₁ >L ₂ ). This brings about the non-contact state between the electrodes 22V _s1 and 22V _e1 and the conductor portion as described above, ie, the open state of the V-phase windings 21V ₁ and 21V- ₂ at the second position.

Further, as shown in the central view of FIG. 1, in the second position, electrodes 22W _s2 and 22W _e2 are in contact with conductor portions 32e and 32f, respectively, while electrodes 22W _s1 and 22W _e 1 Although they are adjacent to the conductor portions 32e and 32f, respectively, they are not in contact with these conductor portions. At the second position, the electrodes 22W _s1 and 22W _e1 are in contact with only the support 34 out of these conductors and the support 34 electrically insulated from these conductors. . The electrode 22W _s1 contacts the support 34 between the conductor portions 32d and 32e, and the electrode 22W _e1 contacts the support 34 between the conductor portions 32e and 32f. As a result, the W-phase winding _21W1 and the W-phase winding _21W2 are opened.

Here, in the first embodiment, the distance between the electrode 22W _s1 and the electrode _{22W e1} in the direction in _which the plurality of electrodes and the plurality of conductors are arranged. is set to _{a value larger than the width L 2 of} the conductor portion 32f (the same applies to other conductor portions) (L ₁ >L ₂ ). As a result, at the second position, the electrode 22W _s1 and the electrode 22W _e1 are brought into the non-contact state as described above, ie, the W-phase winding 21W ₁ and the W-phase winding 21W ₂ are open.

As described above, in the second position of the movable portion 33, the connection state of each phase winding of the three-phase AC motor is in the open state.

As shown in the lower diagram of FIG. 1, at the third position, the electrode 22U _s1 is out of contact with the conductor portion and the electrode 22U _e2 is in contact with the conductor portion 32b, as in the second position. Further, the electrode 22U _s2 and the electrode 22U _e1 are short-circuited by the conductor portion 32a. This electrically connects the winding end _Ue1 of the U-phase winding _21U1 and the winding start _Us2 of the U-phase winding _21U2 . That is, U-phase winding _21U1 and U-phase winding _21U2 are connected in series.

At the third position, as in the second position, the electrode 22V _s1 is out of contact with the conductor portion and the electrode 22V _e2 is in contact with the conductor portion 32d. Furthermore, the electrode 22V _s2 and the electrode 22V _e1 are short-circuited by the conductor portion 32c. As a result, the winding end _Ve1 of the V-phase winding _21V1 and the winding start _Vs2 of the V-phase winding _21V2 are electrically connected. That is, the V-phase winding _21V1 and the V-phase winding _21V2 are connected in series.

Furthermore, at the third position, the electrode 22W _s1 is out of contact with the conductor portion and the electrode 22W _e2 is in contact with the conductor portion 32f, as in the second position. Furthermore, the electrode _22Ws2 and the electrode _22We1 are short-circuited by the conductor portion 32e. As a result, the winding end W _e1 of the W-phase winding 21W ₁ and the winding start W _s2 of the W-phase winding 21W ₂ are electrically connected. That is, the W-phase winding _21W1 and the W-phase winding _21W2 are connected in series.

As described above, when the movable portion 33 is at the third position, the windings of each phase of the three-phase AC motor are connected in series as shown in the lower diagram of FIG.

The actuator 31 is driven by a drive control device (not shown). This drive control device drives the actuator 31 according to the winding switching command shown in FIG. 2, thereby setting the stop position of the movable portion 33 to one of the first to third positions described above.

FIG. 6 is a configuration diagram of a winding switching device that is a comparative example with respect to the first embodiment. Note that FIG. 6 also shows the operation of the winding switching device, as in FIG.

In this comparative example, unlike Example 1 (FIG. 1), the distance between the electrode _{22U s1} and the electrode 22U _e1 in the direction in which the plurality of electrodes and the plurality of conductors are arranged. and the end of the electrode 22U _e1 is set to a value smaller than the width L ₂ of _the conductors (32a to 32f) (L ₁ <L ₂ ). In this case, as shown in the central view of FIG. 6, at the second position of the movable portion 33, unlike the first embodiment, the electrode 22U _s1 to which the winding start U _s1 of the U-phase winding 21U ₁ is connected, The electrode 22U _e1 to which the winding end U _e1 of the U-phase winding 21U ₁ is connected is in contact with the conductor portion of the movable portion 33 . Therefore, U-phase winding _21U1 and U-phase winding _21U2 are not in an open state. Similarly, V-phase winding 21V ₁ and V-phase winding 21V ₂ as well as W-phase winding 21W ₁ and W-phase winding 21W ₂ do not open. Note that "L ₃ " in FIG. 6 will be referred to in the description of the second embodiment to be described later.

As described above, according to the first embodiment, the winding switching device can switch the connection state of the windings of the electric motor between the series connection and the parallel connection, and open the windings. This makes it possible to switch the connection state of the windings of the electric motor, while suppressing an increase in the size of the electric motor drive system. Furthermore, in the first embodiment, in order to provide the winding switching device with a winding opening function, at a predetermined position (the above-described second position) within the range of movement of the movable part 33 for switching the connection state, The winding start and winding end of each phase winding (21U ₁ , 21V ₁ , 21W ₁ in FIG. 1) should not come into contact with the conductor portion of the movable portion 33 . As a result, even though the winding switching device has a winding opening function, the configuration of the winding switching device is not complicated, and the winding switching device itself does not become large. In addition, since the movable portion 33 is linearly driven by the actuator 31 to switch the connection of the windings, the dimension in the width direction of the winding switching device can be reduced. Therefore, when installing the winding switching device in the motor drive system, it can be installed even if there is a restriction on the width dimension.

FIG. 7 is a configuration diagram of a winding switching device that is Embodiment 2 of the present invention. 7 also shows the operation of the winding switching device. To avoid complication of the drawing, most of the reference numerals indicating the parts of the winding switching device are shown only in the upper drawing of FIG.

Differences from the first embodiment are mainly described below.

In the second embodiment, as shown in the upper diagram of FIG. 7, electrodes (22U _si , 22U _ei , 22V _si , 22V _ei , 22W _si , 22W _ei : i=1, 2) are arranged differently. That is, in the second embodiment, the twelve electrodes 22U _s1 , 22U _s2 , 22U _e1 , 22U _e2 , 22V _e2 , 22V _e1 , 22V _s2 , 22V _s1 , 22W _e2 , 22W _e1 , 22W _s2 and 22W _s1 are In this order, they are arranged side by side at intervals in a predetermined direction, in the second embodiment, in a direction away from the actuator 31 side.

As a result, between the U-phase winding connection electrode group and the V-phase winding connection electrode group, the electrode 22U _{e2 to which the winding end U e2 of} the U-phase winding 21U2 is connected and the V-phase winding _21V2 are connected _. The electrode 22V _e2 to which the winding end _Ve2 is connected is arranged adjacently. As described above, the electrodes 22U _e2 and 22V _e2 form the neutral point N, and therefore always have the same potential. Therefore, the distance between the electrodes 22U _e2 and the electrodes 22V _e2 , in FIG. 7, the distance _L4 between the ends of the electrodes 22U _e2 and the ends of the electrodes 22V _e2 facing each other is reduced without impairing electrical reliability. can do. For example, _L4 is the distance between the V-phase winding connection electrode group and the W-phase winding connection electrode group in the aforementioned comparative example (FIG. 6), that is, the distance _L3 between the electrode 22V _e2 and the electrode 22W _s1 . can also be set to a small value. Therefore, the size of the winding switching device 9 can be reduced.

In addition, in the present embodiment 2, the arrangement of each electrode in the V-phase winding connection electrode group is different from that in the embodiment 1 (FIG. 1), and the arrangement of each electrode in the V-phase winding connection electrode group is different. are also different. Therefore, between the V-phase winding connection electrode group and the W-phase winding connection electrode group, the electrode 22V _s1 to which the winding start V _s1 of the V-phase winding 21V1 is connected and the W-phase winding _21W2 are connected _. The electrode 22W _e2 to which the winding end _We2 is connected is arranged adjacent to it. The electrode 22V _s1 is connected to the V phase of the three-phase AC power supply, and the electrode 22W _e2 constitutes the neutral point N. Therefore, the electrical state between the V-phase winding connection electrode group and the W-phase winding connection electrode group is the same as in Example 1 (FIG. 1) and the comparative example (FIG. 6). The interval between the electrode group and the W-phase winding connection electrode group can also be made the same as in Example 1 (FIG. 1) and the comparative example (FIG. 6). Therefore, in the second embodiment, L ₄ is the distance between the V-phase winding connection electrode group and the W-phase winding connection electrode group, that is, the distance between the electrode 22V _s1 and the electrode 22W _e2 ("L ₃ ) is set to a value smaller than That is, in the second embodiment, in order to reduce the size of the winding switching device 9, it is effective to configure the neutral point N between the adjacent electrode groups so that the electrodes always having the same potential are adjacent to each other. works. As a result, the size of the winding switching device can be reliably reduced.

In the second embodiment, the configuration other than that described above, including the relationship between L ₁ and L ₂ (L ₁ >L ₂ ) shown in FIG. 1, is the same as the first embodiment.

As described above, according to the second embodiment, the winding switching device can open the windings of the motor, and the size of the winding switching device can be reduced.

FIG. 8 is a configuration diagram of a winding switching device that is Embodiment 3 of the present invention. 8 also shows the operation of the winding switching device. To avoid complication of the drawing, most of the reference numerals indicating each part of the winding switching device are shown only in the upper drawing of FIG. In addition, FIG. 8 also shows a cross-sectional view taken along the line A-A'.

Differences from the first embodiment are mainly described below.

As shown in the AA' sectional view, the winding switching device 9 of the third embodiment has a substantially cylindrical outer shape. Electrodes (22U _si , 22U _ei , 22V _si , 22V _ei , 22W _si , 22W _ei : i=1, 2) connecting the respective phase windings are arranged inside a substantially cylindrical case. A movable portion 33 having conductor portions (32a to 32f) has a substantially cylindrical shape.

Since the electrodes that connect each phase winding are arranged inside the substantially cylindrical case, even if the electrodes are misaligned or the center position of the movable part 33 is misaligned, the electrodes can be applied to the movable part 33 with a uniform force. come into contact with As a result, the service life of the electrodes and conductors is lengthened, and the replacement cycle of the electrodes and conductors or the winding switching device itself can be lengthened.

In the third embodiment, including the relationship between _L1 and _L2 ( _L1 > _L2 ) shown in FIG. 1 (the relationship between _Lt and _Ls in FIG. 8 ( _Lt > _Ls )), is the same as that of the first embodiment.

As described above, according to the third embodiment, the winding switching device 9 can open the windings of the motor, and the reliability and maintainability of the winding switching device 9 are improved.

In addition, in the third embodiment, the arrangement of the electrodes in the second embodiment may be applied. Thereby, the longitudinal dimension of the cylindrical winding switching device 9 can be reduced.

FIG. 9 is a configuration diagram of an electric railway vehicle that is an embodiment of the present invention.

The electric railway vehicle shown in FIG. 9 is driven by a rotating electrical machine drive system 1 including a three-phase AC motor 2 (M). As the rotary electric machine drive system 1, one embodiment of the present invention shown in FIG. 2 is applied. Furthermore, electric power is supplied to the rotary electric machine drive system 1 from the overhead wire 11 via a current collector. The overhead wire 11 may be either a DC overhead wire or an AC overhead wire. In the case of AC overhead lines, the electric railway vehicle is equipped with an AC/DC converter as a DC power supply (“3” in FIG. 2). An electrical ground in the electric railway vehicle is grounded via wheels 13 and rails 12 .

The three-phase AC electric power from the inverter main circuit in the rotary electric machine drive system 1 drives the three-phase AC electric motor 2 at variable speeds. The three-phase AC motor 2 is mechanically connected to the axle of the electric railway vehicle, and the three-phase AC motor 2 controls the running of the electric railway vehicle.

Any one of Embodiments 1 to 3 is applied as a winding switching device provided in a rotary electric machine drive system.

According to the above-described embodiment, by switching the winding connection state of the three-phase AC motor 2 by the winding switching device, the electric railway vehicle can be operated with high efficiency. Furthermore, since the winding switching device has a winding opening function, an increase in the size of the electric motor driving system can be suppressed even though the electric motor driving system is equipped with the winding switching device. Therefore, the electric motor drive system including the winding switching device can be easily mounted on the electric railway vehicle.

In addition, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. Moreover, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

For example, a permanent magnet synchronous motor, a wound field synchronous motor, an induction motor, a switched reluctance motor, and the like can be applied as the rotating electric machine.

In addition to electric railway vehicles, the rotating electric machine drive system can be applied to electric equipment that operates at variable speeds, such as electric vehicles, hybrid vehicles, and construction machinery.

1 rotary electric machine drive system, 2 three-phase AC motor, 3 DC power supply, 4 capacitor,
5 semiconductor switching element, 6 power module, 7 freewheeling diode,
8 three-phase AC power supply, 9 winding switching device, 10 control device, 11 overhead wire,
12 rails, 13 wheels, 21 three-phase winding terminal group,
21U ₁ , 21U ₂ U-phase windings,
21V ₁ , 21V ₂ V-phase windings,
21W ₁ , 21W ₂ W-phase windings,
22U _s1 , 22U _s2 , 22U _e1 , 22U _e2 electrodes,
22V _s1 , 22V _s2 , 22V _e1 , 22V _e2 electrodes,
22W _s1 , 22W _s2 , 22W _e1 , 22W _e2 electrodes,
31 Actuator, 32a to 32f Conductor, 33 Movable Part

Claims (8)

In a winding switching device for switching parallel connection and series connection of a plurality of windings of a rotating electric machine,
a plurality of electrodes to which the plurality of windings and a power source are connected;
a movable portion that is in contact with the plurality of electrodes and includes a plurality of conductor portions;
an actuator that drives the movable part;
with
Depending on the state of contact between the plurality of electrodes and the plurality of conductors,
At the first stop position of the movable part, the plurality of windings are connected in parallel,
At the second stop position of the movable part, the plurality of windings are open,
the plurality of windings are connected in series at a third stop position of the movable part ;
the plurality of electrodes,
a first electrode connected to the winding start of the winding and connected to the power supply;
a second electrode to which the winding end of the winding is connected;
including
the distance between the end of the first electrode and the end of the second electrode is greater than the width of the conductor;
At the second stop position, the conductor portion is positioned between the first electrode and the second electrode and is out of contact with the first electrode and the second electrode. A winding switching device characterized by: In the winding switching device according to claim 1,
The position of the movable part is
in the high speed range of the rotating electric machine, the first stop position;
at the second stop position when the power supply is stopped;
The winding switching device , wherein the winding switching device is in the third stop position in a low speed range of the rotating electric machine . In the winding switching device according to claim 1,
The winding switching device , wherein the second stop position is between the first stop position and the third stop position . In a winding switching device for switching parallel connection and series connection of a plurality of windings of a rotating electric machine,
a plurality of electrodes to which the plurality of windings and a power source are connected;
a movable portion that is in contact with the plurality of electrodes and includes a plurality of conductor portions;
an actuator that drives the movable part;
with
Depending on the state of contact between the plurality of electrodes and the plurality of conductors,
At the first stop position of the movable part, the plurality of windings are connected in parallel,
At the second stop position of the movable part, the plurality of windings are open,
the plurality of windings are connected in series at a third stop position of the movable part;
the plurality of electrodes,
a first electrode to which a first-phase winding of the rotating electric machine is connected among the plurality of windings;
a second electrode to which a second-phase winding of the rotating electric machine is connected among the plurality of windings;
including
The winding switching device , wherein the first electrode and the second electrode are adjacent to each other and form a neutral point . In the winding switching device according to claim 4 ,
the plurality of electrodes,
a third electrode to which a third-phase winding of the rotating electric machine is connected among the plurality of windings;
a fourth electrode to which the second-phase winding of the rotating electric machine is connected among the plurality of windings;
including
the third electrode and the fourth electrode are adjacent to each other;
the third electrode constitutes the neutral point;
The winding switching device , wherein the power source is connected to the fourth electrode . In a winding switching device for switching parallel connection and series connection of a plurality of windings of a rotating electric machine,
a plurality of electrodes to which the plurality of windings and a power source are connected;
a movable portion that is in contact with the plurality of electrodes and includes a plurality of conductor portions;
an actuator that drives the movable part;
with
Depending on the state of contact between the plurality of electrodes and the plurality of conductors,
At the first stop position of the movable part, the plurality of windings are connected in parallel,
At the second stop position of the movable part, the plurality of windings are open,
the plurality of windings are connected in series at a third stop position of the movable part;
A winding switching device characterized by having a cylindrical outer shape . a rotating electric machine;
an inverter that supplies AC power to the rotating electric machine;
In a rotating electric machine drive system comprising
A winding switching device is connected between the rotating electrical machine and the output of the inverter to switch parallel connection and series connection of the plurality of windings of the rotating electrical machine,
A rotary electric machine drive system, wherein the winding switching device is the winding switching device according to any one of claims 1, 4 and 6. In an electric device operated at variable speed by a rotating electric machine drive system,
An electric machine, wherein the rotating electrical machine drive system is the rotating electrical machine drive system according to claim 7 .

Images