JP2001309623A - Motor and inverter unit comprising the motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that a usual structure requires a number of parts for constituting an inverter circuit that induce a unit to be sizable. SOLUTION: A motor is reduced in size and weight by setting 180 deg. different in phase of inductance variations of a first winding 65 and a second winding 66 that are mounted to a first substance 63 and by forcing the motor driven by the inverter circuit 42 that consists of two switching elements 54, 60.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to general households and factories,
The present invention relates to an electric motor used for an air conditioner, a household appliance, a rotary cooker, and the like, which is used for industrial use in stores, offices, and the like, and an inverter device including the electric motor.

[0002]

2. Description of the Related Art Inverter devices for controlling electric motors used in conventional air conditioners, household appliances, rotary cookers, etc.
The configuration is as shown in FIG. FIG. 10 is a circuit diagram of a conventional inverter device.

[0003] That is, the conventional inverter device comprises a DC power supply 1 and an inverter circuit 2 including a winding of a motor 3. The DC power supply 1 includes a rectifier circuit 5 connected to a commercial power supply 4, a choke coil 6 for smoothing connected to an output of the rectifier circuit 5, and a capacitor 7 for smoothing.

[0004] The inverter circuit 2 operates by receiving a DC voltage from the DC power supply 1.
9, 10, 11, 12, 13 and diodes 14, 1
5, 16, 17, 18, and 19, and a control circuit 20 for controlling ON / OFF of each switching element.

The windings of the electric motor 3 are composed of windings 21, 22, 2
3, which are connected to the respective switching elements. FIG. 10 is a cross-sectional view illustrating the configuration of the electric motor 3. The electric motor 3 includes a rotor 24 and a stator 25, and the rotor 24 is provided rotatably about a shaft 26.

The rotor 24 has an iron core having four teeth, and the stator 25 has an iron core 28 having six teeth.
And coils 29, 30, 3 wound around each tooth
1, 32, 33, and 34.

FIG. 12 is a connection diagram showing connection of each coil of the electric motor 3. Coil 29, Coil 30, Coil 31
And the coil 32, and the coil 33 and the coil 34 are connected in series, respectively. Also, as shown in FIG.
The coils are arranged at intervals of 60 ° so that the electric motor 3 becomes a three-phase motor. That is, the series body of the coil 29 and the coil 30 constitutes one phase winding 21 of the three phases, and the series body of the coil 31 and the coil 32 similarly constitutes the other one phase winding 22 of the three phases. , And the series body of the coil 33 and the coil 34 forms the other one-phase winding 23 of the three phases.

The terminals a, b, c, d, e, f of each winding are:
As shown in FIG.
5, 16, 17, 18, and 19.

With the above configuration, when the rotor 24 rotates about the shaft 26, the size of the gap between the teeth of the rotor 24 and the teeth of the stator 25 changes with time. Becomes As a result, the value of the self-inductance of each coil increases or decreases as the rotor 27 rotates. The control circuit 20 includes switching elements 8, 9, 10, 11, 12,
13 are turned on and off, and the series bodies 21, 2
A current is supplied to 2 and 23 in order. At this time, power is supplied to the series body at a timing when the self-inductance of each coil increases, so that torque is efficiently generated. Thus, the rotor 27 rotates, and the rotation is transmitted to the outside using the shaft 26 and used.

[0010]

The conventional structure has a problem that the number of components constituting the inverter circuit is large and that the apparatus becomes large.

[0011]

According to the present invention, a phase difference between changes in inductance of a first winding and a second winding provided on a first object is set to 180 °. The motor is reduced in size and weight by being driven by an inverter circuit composed of individual switching elements.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The first aspect of the present invention is a first aspect of the present invention.
By setting the phase difference of the change in inductance between the first winding and the second winding provided on the object to 180 °, the inverter can be driven by an inverter circuit composed of two switching elements. As a result, the motor is reduced in size and weight.

According to a second aspect of the present invention, when the first object and the second object are relatively moved in any direction,
The first winding and the second winding are provided such that there is a period in which the inductance of both increases.
To supply current to the second winding or the second winding,
The motor is capable of reliably generating thrust or torque and has excellent starting performance from a stopped state.

According to the third aspect of the present invention, the length of the gap between the magnetic body of the first object and the magnetic body of the second object is inclined to reliably generate thrust or torque. The motor has excellent starting performance from a stopped state.

According to a fourth aspect of the present invention, there is provided a voltage doubler rectification type DC power supply having two capacitors connected in series with an inverter circuit, and a high potential side diode and a low potential side switching element in series. And a second series circuit in which a high-potential-side switching element and a low-potential-side diode are connected in series. Both ends of the first series circuit and the second series circuit Connected in parallel, both ends of which are connected to both ends of a DC power supply, and one terminal of the first winding is connected to a connection point between the high potential side diode and the low potential side switching element; The other terminal of the line is connected to the connection point of the two capacitors, one terminal of the second winding is connected to the connection point of the high potential side switching element and the low potential side diode,
The other terminal of the winding is connected to the connection point of the two capacitors, so that the number of switching elements to be used can be two, so that the inverter device has a very simple configuration.

According to a fifth aspect of the present invention, each winding of the three-phase motor has two diodes connected to the high potential side of the DC power supply and two switching elements connected to the low potential side. Used by being driven by two series circuits and one series circuit having one switching element connected to the high potential side of the DC power supply and one diode connected to the low potential side An inverter device having a very simple configuration in which the number of switching elements to be used is three is provided.

According to a sixth aspect of the present invention, each winding of the three-phase motor has two switching elements connected to the high potential side of the DC power supply and two diodes connected to the low potential side. Two series circuits, one diode connected to the high potential side of the DC power supply and one diode connected to the low potential side
The inverter device is driven by one series circuit having three switching elements, and the number of switching elements to be used is three.

[0018]

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described. FIG. 1 is a circuit diagram showing a configuration of a circuit of the inverter device of the present embodiment.

The inverter device of the present embodiment has a motor 43
Is driven. That is, the DC power supply 41
, An inverter circuit 42 and an electric motor 43. The DC power supply 41 includes a commercial power supply 44 and a commercial power supply 4.
4 and a smoothing choke coil 46 connected to the AC side of the rectifier circuit 45. The rectifier circuit 45 is of a voltage doubler rectifier type using two electrolytic capacitors 47 and 48 connected in series for smoothing.

The inverter circuit 42 has a first series circuit 55, a second series circuit 61, and a control circuit 62. The first series circuit 55 is composed of a diode 53 and a switching element 54,
The diode 53 is connected to the high potential side of 1 and the switching element 54 is connected to the low potential side. The second series circuit 61 includes a switching element 60 and a diode 59. The switching element 60 is provided on the high potential side of the DC power supply 41, and the diode 59 is provided on the low potential side of the DC power supply 41. Are connected. Both ends of the first series circuit 55 and the second series circuit 61 are connected in parallel, and both ends are connected to both ends of the capacitors 47 and 48 connected in series.

The electric motor 43 includes a first winding 65, a second winding 66, and a position detector 67. First winding 6
5 is connected between the common terminal 68 and the terminal 69, and the second winding 66 is connected between the common terminal 68 and the terminal 71. The terminal 69 connecting the first winding 65 has the first
Is connected to the connection point between the diode 53 and the switching element 54 constituting the series circuit 55 of the first winding 6.
5 is connected to the connection point between the capacitors 47 and 48. The connection point between the switching element 60 and the diode 59 constituting the second series circuit is connected to the terminal 71 connecting the second winding 66. The other end of the second winding 66 is the common terminal 68.

The switching element 54 and the switching element 60 are both ON / OFF controlled by signals Q1 and Q2 from a control circuit 62 which has received a signal S from a position detector 67.

In this embodiment, the position detector 67 is
An optical type generally called a photo interrupter or the like is used, and a first object 63 shown in FIG.
A high or low signal is output according to the relative position of the second object and the second object, that is, the rotation angle.

FIG. 2 is a sectional view of the electric motor 43. That is, (A) is a plan view seen from above illustrating the shape of the upper layer portion of the electric motor 43 of the present embodiment, (A) is a side view illustrating the overall shape, and (C) illustrates the shape of the lower layer portion. FIG. 4 is a plan view as viewed from the lower surface of the light emitting device.

The electric motor 43 of this embodiment has a first object 63 having a magnetic material 123, a first object 63a having a magnetic material 124, and a first object 63, 63a relatively to the first objects 63, 63a. It comprises a movable second object 64. The second object 64 includes a coil 114 and a coil 115
The first winding 65 and the coil 118
And a second winding 66 constituted by the coil 119. The coil 114, the coil 115, the coil 118, and the coil 119 are formed by stacking silicon steel plates.
21 is provided on the tooth portion. In the present embodiment, the coil 114 and the coil 115 are set at an angle of 180 °, and the coil 114 and the coil 115 are
The coils 118 and 114 are arranged so as to have an angle of 0 ° and the coil 118 and the coil 114 have an angle of 90 °.

The shaft 120 outputs the power of the electric motor 43 to a mechanical load, and is provided through a center of a first object 63 generally called a rotor or a rotor and a first object 63a. ing. The shaft 120 is rotatably supported by bearings 125 and 126.

The magnetic body 123 forming the first object 63 and the magnetic body 124 forming the first object 63a are both as shown in FIGS. 2A and 2C. The outer periphery has a spiral shape. For this reason, the gap length L between the teeth of the iron core 121 constituting the second object 64
g has, for example, an interval ** that changes periodically ** with the rotation of the first object 63 and in which the gap length Lg gradually decreases.

FIG. 3 shows the first winding 65 of the electric motor 43.
FIG. 9 is a connection diagram showing connection between the second winding 66 and the second winding 66. In this embodiment, the coils 114 and 115 and the coils 118 and 119 are arranged so as to have opposite polarities. That is, the black circle mark on one side of each coil indicates the polarity of the coil, and when a current is applied from the side with the black circle mark, the inside of the iron core 121, that is, the magnetic property of the first object 63. This indicates that an S pole is generated on the second object 64 side facing the body 123 and the magnetic body 124.

The coil 114 and the coil 115 are connected in series to form the first winding 65, and the coil 118 and the coil 1
Reference numeral 19 is connected in series to form a second winding 67.

With the above configuration, when the first object 63 makes a rotational movement in the direction indicated by the arrow in FIG. 2, there is a section in which the gap length Lg gradually decreases depending on the angle of rotation. In accordance with the change of Lg, the inductance of the first winding 65 and the second winding 66 both changes periodically.

The waveform of the inductance change is
The first winding and the second winding have a phase difference of approximately 180 degrees.

The inductance here is a self-inductance, and in the present embodiment, the first winding 65 and the second winding 6
Since the magnetic circuits 6 are almost completely independent, the mutual inductance is almost zero.

Here, the phase difference is an electrical angle,
In this embodiment, the cycle of the inductance change is half the rotation angle (mechanical angle), and the electrical angle is two times the rotation angle (mechanical angle).
Double.

FIG. 4 is an operation waveform diagram of the inverter device of the first embodiment. FIG. 4A shows the inductance value L1 of the first winding 65, and FIG. Of the winding 66 of FIG. 4 (c) shows the waveform of the output signal S of the position detector 67, FIG. 4 (d) shows the waveform of the on / off signal of the switching element 54 as Q1, and FIG. 4 (e) shows the waveform of the switching element 60. The waveform of the on / off signal is shown as Q2, and FIG. 4F shows the waveform of the current i1 flowing through the first winding 65 in FIG.
Shows the waveform of the current i2 flowing through the second winding 66.

In each of the figures, the abscissa indicates the rotation angle, that is, the mechanical angle, and the rotation direction is the first object 6.
The direction 3 is the direction indicated by the arrow. The electrical angle is twice the mechanical angle as described above.

The operation of this embodiment will be described below.
In the present embodiment, the magnetic body 123 forming the first object 63
And a magnetic body 124 forming the first object 63a,
The gap length Lg formed by the teeth of the iron core 121 forming the object 64 is inclined. Therefore, for example, when the first object 63 and the first object 63a are rotated in the counterclockwise direction, the first winding 65 arranged on the teeth of the iron core 121 constituting the second object 64 And the inductances L1, L2 of the second Makise committee 66
Fluctuates periodically as shown in FIGS. 4A and 4A. This variation gradually increases as the air gap gradually decreases during a mechanical angle of 120 degrees (electrical angle of 240 degrees), and rapidly decreases with a sudden increase of the air gap during a mechanical angle of 60 degrees (electrical angle of 120 degrees). It has become. In addition, from a mechanical angle of 75 degrees to 1
The period of 05 degrees and the period from 165 degrees to 195 degrees of mechanical angle are periods in which the inductance L1 of the first winding 65 and the inductance L2 of the second winding 66 both increase.

As shown in FIG. 4C, the position detector 67 outputs a signal indicating a high signal at 90 degrees between the mechanical angle of 85 degrees and the mechanical angle of 175 degrees as an S signal. At 90 degrees between the mechanical angles of 175 degrees and 265 degrees, a signal indicating b is output. That is, the position detector 67 generates a signal that repeats the high period and the low period in a cycle of the mechanical angle of 180 degrees.

Further, as shown in FIG. 4D, the signal Q1 for driving the switching element 54 generated by the control circuit 62 is turned on and off during the period when the S signal of the position detector 67 is low. Off for the period. The ON period is within a period in which the inductance L1 of the first winding 65 shown in FIG.

Similarly, the signal Q2 for driving the switching element 60 generated by the control circuit 62 is turned on when the S signal of the position detector 67 is high and turned off when it is low. The ON period is a period during which the inductance L2 of the second winding 66 increases.

Generally, the amount of increase in self inductance is dL
When the current i passes through / dθ, reluctance torque is generated, and power of 0.5 × (square of i) × dL / dθ is generated. Current i1 flowing through first winding 65
Is within the period in which the inductance L1 increases, and thus generates a reluctance torque in the magnetic body 123. This electric current i1 has a mechanical angle of 85 degrees and a mechanical angle of 265.
Even if the switching element 54 is turned off, the current i1 does not immediately become zero due to the energy stored in the inductance L1. That is, the timing when the current i1 becomes 0 is 15 mechanical angles.
The position is 100 degrees or 280 degrees after the position.

During this time, the diode 53 is in a conductive state, the potential of the collector of the switching element 54 on the low potential side rises to almost the potential of the plus terminal of the capacitor 48, and the charging current flows through the capacitor 48. Supplied. Even during the period when the diode 53 is in the conductive state, the inductance L1 continues to increase, so that the electric power is regenerated in the capacitor 48 and the torque is still generated.

During this period, since the current i2 starts to flow through the second winding 66, the torque (mechanical output power)
Is also generated in the magnetic body 124.

Therefore, part of the current of the diode 53 flows to the switching element 60, and the remaining current charges the capacitor 48. The same operation is performed when the current i2 flowing through the second winding 66 is turned off.

As described above, according to the present embodiment, since there is a period in which the inductance L1 of the first winding 65 and the inductance L2 of the second winding 66 both increase, there is a continuous period. Reluctance torque can be obtained, operation with little torque ripple can be performed, and at start-up, at any mechanical angle position, at least one of L1 and L2 has an inductance in counterclockwise rotation. Because of the increase, the starting torque in the direction indicated by the arrow in FIG. 2 can be obtained, and the starting can be performed.

Second Embodiment Next, a second embodiment of the present invention will be described. FIG. 5 is a connection diagram showing a circuit of the inverter device of the present embodiment.

In this embodiment, the electric motor 43 includes two first motors 43.
Windings 65 and 165, and a second winding 66,
The total number of the first winding and the second winding is three.

DC power supply 4 constituting inverter circuit 42
1 is a double voltage rectification type having two capacitors 47 and 48 connected in series, as in the first embodiment, and a diode 153 connected to the high potential side and a switching element 154 connected to the low potential side. Are connected in series to the first series circuit 155 in addition to the configuration of the first embodiment. Therefore, the configuration has three series circuits of the first series circuits 55 and 155 and the second series circuit 61.
The first series circuit 55, the first series circuit 155, and the second
Are connected in parallel, and are connected to both ends of the DC power supply 41.

One terminal of the first winding 165 is
It is connected to a connection point between the diode 153 and the switching element 154, and the other terminal of the first winding 165 is connected to a connection point between the two capacitors 47 and 48.

The control circuit 162 includes a position detector 167a,
The signal S is received from 167b and 167c, and the on / off of the switching elements 54, 154 and 60 is controlled.

That is, since the present embodiment has a three-phase configuration, three position detectors 167a, 167b, and 167c are used.

FIG. 6 is a sectional view showing the structure of the electric motor 43 of this embodiment. In the present embodiment, the second object 64 has an iron core 199. The iron core 199 has six teeth arranged at intervals of 60 degrees. Coil 200, coil 201, coil 2
02, a coil 203, a coil 204, and a coil 205 are arranged.

The first object 63 is constituted by a magnetic body 210 using an iron core. The first object 6
Reference numeral 3 has four teeth provided at intervals of 90 degrees, and is rotatable about a shaft 220.

FIG. 7 shows the first winding 6 of the electric motor of this embodiment.
5 is a connection diagram of a first winding 165 and a second winding 66. FIG. The black circle on one side of each coil indicates the polarity of the coil, and when a current is applied from the side with the black circle, the inside of the second object 64, that is, the opposition of the first object 63. This indicates that an S pole is generated on the side where the noise occurs.

The coils 200 and 201 are connected in series to form a first winding 65, and the coils 202 and 203 are connected in series to form a first winding 165.
4 and the coil 205 are connected in series to form the second winding 67. That is, the coil 201 and the coil 203 constitute the winding of the three-phase motor.

In this embodiment, the gap formed by the teeth of the magnetic body 210 and the teeth of the iron core 199 changes periodically as described in the first embodiment.
Therefore, the first windings 65, 165 constituting the three-phase windings
And the inductance value of the second winding 66 changes according to the rotational movement of the first object 63.

As shown in FIG. 7, in this embodiment, the output terminals of each winding are a common terminal 68, a terminal 69,
The total number of terminals 169 and 71 is four. The first winding 65, the first winding 165, and the second winding 66 are arranged at an electrical angle of 120 degrees from each other, and one end of each winding is connected to a common terminal 68. I have.

In the second winding 66, the direction of the magnetic flux generated when a current flows from the common terminal 68 is opposite to the direction of the first winding 65 and the first winding 165. Connected.

Hereinafter, the operation of this embodiment will be described.
When the switching element 54 is turned on, a current flows from the common terminal 68 to the terminal 69 in each winding of the present embodiment,
Magnetic flux is generated in the direction A shown in FIG. Similarly, when the switching element 154 is turned on, a current flows from the common terminal 68 to the terminal 169, and a magnetic flux is generated in the direction B shown in FIG. On the other hand, when the switching element 60 is turned on, the current flows through the winding 66 from the terminal 71 to the common terminal 68.
05 has a polarity opposite to that of the coils of the other phases, so that a magnetic flux is generated in the direction of C as a result.

The directions A, B, and C of the magnetic flux are in a well-balanced form shifted by 120 degrees. That is, the first object 63 is smoothly driven to rotate.

FIG. 8 is a waveform diagram showing the operating state of the device of this embodiment. FIG. 8A shows an output waveform of the position detector 167a shown in FIG. 5, and FIG.
FIG. 8C shows the output waveform of the position detector 167c.
3 shows an output waveform of the first embodiment. FIG. 4 (D), FIG.
4E and FIG. 4F show output waveforms from the control circuit 162, and show waveforms of gate signals for turning on / off the switching element 54, the switching element 154, and the switching element 60, respectively.

For example, as shown in FIG.
When the switching element 54 is turned on, the capacitor 4
The current from 7 flows from the common terminal 68 to the terminal 69 via the first winding 65, and the first object 63 receives a reluctance torque (rotational force).

At time t6, when the switching element 54 is turned off by the control circuit 62, the energy stored in the inductance of the first winding 65 is reduced by the diode 5
3 and stored in the capacitor 48.

The same applies when the switching element 154 is turned off at time t4.

During the period from time t6 to time t8, the second winding 6
6, the first object 63 also receives reluctance torque.

At time t8, when switching element 60 is turned off, a little more current flows through diode 59 to second winding 66 due to the energy stored in the inductance of second winding 66. . At this time, this current continues to flow until the energy stored in the inductance is almost completely recovered by the capacitor 47.

As described above, in this embodiment, the inverter circuit 42 has a very simple structure of three phases and three stones in particular, and the structure of the drive circuit required inside the control circuit 162 for turning on and off each switching element. Is easy,
At the time of turn-off, the energy stored in the inductance can be recovered by the capacitors 47 and 48 and can be used again.

In this embodiment, as shown in FIG. 5, the inverter circuit 42 includes two first series circuits 55
And one second series circuit 61. That is, the diodes 53 and 153 connected to the high potential side of the DC power supply 41, the switching elements 54 and 154 connected to the low potential side, and the switching element 60 connected to the high potential side of the DC power supply 41. And a diode 59 connected to the low potential side. However, as shown in FIG. 9, this configuration includes a diode 53 connected to the high potential side of the DC power supply 41 and a switching element 54 connected to the low potential side.
And a switching element 60 and a switching element 154 connected to the high potential side of the DC power supply 41,
A series circuit 61 and a series circuit 1 composed of a diode 59 and a diode 153 connected to the low potential side.
Even if it is constituted by 55, there is no problem.

In this type of electric machine called a switched reluctance motor, the direction of the generated torque is in principle irrelevant to the polarity of the current. For example, when the mutual inductance between the first and second windings 65 and 165 and the second winding 66 is small, the second winding 66 does not need to have the opposite polarity in the configuration of the motor 43.

In the present embodiment, the motor 43 generates reluctance torque using a first object having a magnetic material, which operates on a principle generally called a switched reluctance motor. In particular, it is not necessary to use this type, and a type using a permanent magnet may be used.

As described above, according to the present embodiment, the required number of switching elements is three in total, which is a very simple configuration that requires only half the configuration of the conventional three-phase motor. Things. In this embodiment, since a three-phase motor is used, the direction of rotation can be freely changed depending on the order in which the three switching elements are turned on.

In this embodiment, since the first series circuit is two and the second series circuit is one, a simple configuration in which only one switching element is arranged on the high potential side is required. I have. However, the number of the first series circuit may be one and the number of the second series circuits may be two. Even in this case, a three-phase motor can be driven.

In the first and second embodiments, the electric motor 43 has a structure in which the first object 63 is rotatably provided inside the second object 64. The present invention is not limited to such a configuration, and a first object generally referred to as an outer rotor is provided rotatably on the outside of a second object, or is provided with an axial gap. The first object and the second object are opposed to each other in a plane, and the first object and the second object are both linearly shaped to perform linear motion. The first object as described in each embodiment moves, and the second object is stationary as described in each embodiment. It is not limited to. Conversely, there is no problem even if the first object is stationary and the second object moves, or if both the first object and the second object move. .

(Embodiment 3) Next, a third embodiment of the present invention will be described. FIG. 9 is a circuit diagram showing a configuration of the inverter device of the present embodiment. The inverter device of this embodiment is a motor 43 having three-phase windings 65, 66, and 165.
And an inverter circuit 42 for supplying a current to each of the three-phase windings 65, 66 and 165.

The winding 65 of the electric motor 43 has a configuration in which the other two windings 66 and 165 are wound in opposite polarities.
The inverter circuit 42 has a double voltage rectification type DC power supply 41 having two capacitors 47 and 48 connected in series.
A series circuit 55 having one diode 53 connected to the high potential side of the DC power supply 41 and one switching element 54 connected to the low potential side; Two switching elements 60 connected to
And 154 and two diodes 59 connected to the low potential side
And 153, and two series circuits 61 and 155. The three series circuits 55, 61 and 155
Are connected in parallel to both ends of the DC power supply 41, and one terminal of each of the three-phase windings 65, 66 and 165 is connected to a connection point of the two capacitors. The other terminals of the three-phase windings 65, 66 and 165 are connected to a connection point between a switching element and a diode of the inverter circuit. That is, one terminal of the winding 165 is connected to the connection point between the one terminal diode 59 of the winding 66 and the switching element 60.
One terminal of the winding 65 is connected to a connection point between the switching element 54 and the diode 53.

The switching elements 60 and 154 forming the series circuit 61 and the series circuit 155 are connected to the high potential side of the DC power supply 41, and the diodes 59 and 153 are connected to the low potential side of the DC power supply 41. Connected to the side. The switching element 54 constituting the series circuit 55 is connected to the low potential side of the DC power supply 41, and the diode 53 is connected to the high potential side of the DC power supply 41.

As described above, in the present embodiment, the winding configuration of the three-phase motor 43 is such that the winding 65 has the opposite polarity to the other two windings 66 and 165. Therefore, as described in the above embodiments, torque can be continuously generated in the rotor of the electric motor 43, and the energy stored in the inductance of each winding can be effectively used.

That is, it is possible to realize an inverter device having a very simple configuration in which the number of switching elements used is three. Further, for example, the switching element 5
4 is turned on, the current supplied to the first winding 65 is temporarily absorbed by the capacitor 48 via the diode 53 at the moment when the control circuit 162 turns off the switching element 54, and then the control circuit 162 When the switching element 60 or 154 is turned on, the capacitor 48
The energy absorbed into the motor 43 is supplied to the electric motor 43 again so that the energy can be reused.

[0078]

According to the first aspect of the present invention, there is provided a first object having a magnetic material, and a second object movable relative to the first object. A first winding and a second winding whose inductance periodically changes due to relative movement between the first object and the second object; The change in the inductance of the winding means that when the relative movement of the second object is in a predetermined direction, the structure has a phase difference of approximately 180 degrees and a simple structure that can be driven by two switching elements, thereby reducing the cost. It is intended to realize a smaller, smaller, and lighter electric motor.

According to the second aspect of the invention, the inductance of the first winding and the inductance of the second winding are such that the first object and the second object are relatively moved in either direction. The present invention realizes an electric motor with excellent starting performance that can reliably obtain a thrust or a torque and can be easily started from a stopped state, as a configuration in which there is a period during which both increase.

According to a third aspect of the present invention, the gap between the magnetic material of the first object and the magnetic material of the second object is ** gradually reduced by relative motion. As a result, the present invention realizes an electric motor with excellent starting performance that can reliably obtain thrust or torque and can be easily started from a stopped state.

According to a fourth aspect of the present invention, there is provided the electric motor according to any one of the first to third aspects, and an inverter circuit for driving the electric motor, wherein the inverter circuit comprises: A voltage doubler rectification type DC power supply having two capacitors connected in series, a first series circuit in which a high potential side diode and a low potential side switching element are connected in series, a high potential side switching element and a low potential side switching element. A second series circuit in which potential-side diodes are connected in series, both ends of the first series circuit and the second series circuit are connected in parallel, and both ends are connected to both ends of the DC power supply One terminal of the first winding is connected to a connection point between a high potential side diode and a low potential side switching element, and the other terminal of the first winding is connected to the two capacitors. Connected to a point, one terminal of the second winding is The number of switching elements to be used is such that the potential of the switching element is connected to the connection point of the potential side switching element and the low potential side diode, and the other terminal of the second winding is connected to the connection point of the two capacitors. This is to realize an inverter device having a very simple configuration of two.

The invention according to claim 5 comprises a motor having three-phase windings, and an inverter circuit for supplying current to each of the three-phase windings, wherein the inverter circuits are connected in series. Voltage rectification type DC power supply having a plurality of capacitors, and a DC voltage source connected to the high potential side of the DC power supply.
Two series circuits each having one diode and two switching elements connected to the low potential side, one switching element connected to the high potential side of the DC power supply, and one switching element connected to the low potential side. And one series circuit having a diode, wherein both ends of the three series circuits are connected in parallel to both ends of the DC power supply, and one terminal of the three-phase winding is connected to the diode. And the other end of the three-phase winding is connected to the connection point of the two capacitors, so that the number of switching elements is three.
This realizes an inverter device having a very simple configuration.

The invention according to claim 6 comprises an electric motor having three-phase windings, and an inverter circuit for supplying current to each of the three-phase windings, wherein the inverter circuits are connected in series. Voltage rectification type DC power supply having a plurality of capacitors, and a DC voltage source connected to the high potential side of the DC power supply.
Two series circuits each having one switching element and two diodes connected to the low potential side, one diode connected to the high potential side of the DC power supply, and one switching connected to the low potential side And one end of the three-phase winding is connected to both ends of the three series circuits in parallel, and one end of the three-phase winding is connected to the diode. And the other end of the three-phase winding is connected to the connection point of the two capacitors, so that the number of switching elements is three.
This realizes an inverter device having a very simple configuration.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration of an inverter device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the electric motor. (A) A top view showing the configuration of the upper layer, viewed from above. (A) A side view showing the entire configuration. (C) A plan view of the lower layer showing the shape of the lower layer.

FIG. 3 is a connection diagram showing a configuration of a winding of the electric motor.

FIG. 4 is a waveform diagram showing the operation of the inverter circuit. (A) A waveform diagram showing a change in inductance of the first winding. (A) A waveform diagram showing a change in inductance of the second winding. ) A waveform diagram showing a detection signal of the position detector. (D) A waveform diagram showing a waveform for driving the switching element by the control circuit. (E) A waveform diagram showing a waveform for driving the switching element by the control circuit. Waveform diagram showing waveform of current flowing through wire (g) Waveform diagram showing waveform of current flowing through second winding

FIG. 5 is a circuit diagram showing a configuration of a motor according to a second embodiment of the present invention.

FIG. 6 is a sectional view showing the configuration of the electric motor.

FIG. 7 is a wiring diagram showing a configuration of a winding of the electric motor.

FIG. 8 is a waveform diagram showing the operation of the inverter circuit. (A) A waveform diagram showing a detection signal detected by the position detector. (A) A waveform diagram showing a detection signal detected by the position detector. Waveform diagram showing the detection signal detected by the detector (d) Waveform diagram showing the waveform that the control circuit drives the switching element (e) Waveform diagram showing the waveform that the control circuit drives the switching element (f) Control circuit switching Waveform diagram showing waveforms for driving elements

FIG. 9 is a circuit diagram showing a configuration of an inverter device according to a third embodiment of the present invention.

FIG. 10 is a circuit diagram showing a configuration of an inverter device according to a conventional technique.

FIG. 11 is a sectional view showing the configuration of the electric motor.

FIG. 12 is a connection diagram showing a configuration of a winding of the electric motor.

[Explanation of symbols]

 41 DC power supply 42 Inverter circuit 43 Electric motor 47 Capacitor 48 Capacitor 53 Diode 54 Switching element 55 First series circuit 59 Diode 60 Switching element 61 Second series circuit 62 Control circuit 63 First object 64 First Two objects 65 First winding 66 Second winding 123 Magnetic body 124 Magnetic body 153 Diode 154 Switching element 155 First series circuit 162 Control circuit 165 First winding

Continuation of the front page (72) Inventor Yasudo Kobayashi 1006 Kazuma, Kazuma, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. PP33

Claims (6)

[Claims] A first object having a magnetic material;
And a second object that can move relatively with respect to the first object, the second object having a first winding whose inductance is periodically changed by a relative movement between the first object and the second object. And a change in inductance of the first winding and a change in inductance of the second winding are approximately 180 when the relative movement of the second object is in a predetermined direction.
An electric motor with a phase difference of degrees. 2. The inductance of the first winding and the inductance of the second winding are such that when the first object and the second object are moved relative to each other in any direction, a period in which both of them increase. An electric motor as claimed in claim 1 which is present. 3. A magnetic body included in the first object,
3. The electric motor according to claim 1, wherein a gap between the magnetic body of the object and the magnetic body is gradually reduced by relative motion. 4. 4. An electric motor according to claim 1, comprising an inverter circuit for driving the electric motor, wherein the inverter circuit comprises two serially connected inverter circuits. A double voltage rectification type DC power supply having a capacitor,
It has a first series circuit in which a high potential side diode and a low potential side switching element are connected in series, and a second series circuit in which a high potential side switching element and a low potential side diode are connected in series. Both ends of the first series circuit and the second series circuit are connected in parallel, both ends are connected to both ends of the DC power supply, and one terminal of the first winding is connected to a high potential side diode. And the connection point of the low potential side switching element,
The other terminal of the first winding is connected to a connection point of the two capacitors, and one terminal of the second winding is connected to a connection point of a high potential side switching element and a low potential side diode. An inverter device connected to the other terminal of the second winding and connected to a connection point of the two capacitors. 5. An electric motor having three-phase windings, and an inverter circuit for supplying a current to each of the three-phase windings, wherein the inverter circuit has two capacitors connected in series. A rectified DC power supply, two series circuits each including two diodes connected to the high potential side of the DC power supply and two switching elements connected to the low potential side, and a high potential side of the DC power supply. And one series circuit having one switching element connected to the DC power supply and one diode connected to the low potential side. Both ends of the three series circuits are connected in parallel to An inverter connected to both ends, one terminal of the three-phase winding is connected to a connection point of the diode and the switching element, and the other end of the three-phase winding is connected to a connection point of the two capacitors. apparatus. 6. An electric motor having three-phase windings and an inverter circuit for supplying a current to each of the three-phase windings, wherein the inverter circuit has two capacitors connected in series. A rectifying type DC power supply, two series circuits having two switching elements connected to a high potential side of the DC power supply and two diodes connected to a low potential side, and a high potential side of the DC power supply. A series circuit having one diode connected to the DC power supply and one switching circuit connected to the low potential side. An inverter connected to both ends, one terminal of the three-phase winding is connected to a connection point of the diode and the switching element, and the other end of the three-phase winding is connected to a connection point of the two capacitors. apparatus.