JP2007244022A - Motor drive, load test supporting device and load test device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the cost and size while enhancing regeneration efficiency of a motor drive for driving an AC motor and having a function for regenerating excessive energy during brake operation as electric energy, a load test supporting device for setting predetermined load test conditions to these AC motor and motor drive and a generator driven through the AC motor entirely or partially, and a load test device for achieving the load test. <P>SOLUTION: The motor drive comprises a means for converting AC power into DC power, a motor drive means for driving an AC motor with the DC power, a means being driven through the AC motor to generate power, and a DC regenerative means for regenerating the generated power between the stages of the power conversion means and the motor drive means. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention converts AC power into DC power, drives an AC motor with the DC power, and regenerates surplus energy during braking of the AC motor to these AC power or DC power supply sources. A load test support device for applying a desired load to all or part of the circuit, the AC motor described above, the inverter driving the AC motor, and the generator driven by the motor, and these motors under a predetermined load condition The present invention relates to a load test apparatus for testing any one of an inverter, a motor and a generator.

In recent years, light and small batteries that can supply large amounts of power at low cost have been put to practical use. For example, an internal combustion engine that obtains power necessary for running an automobile or the like is a motor that can be driven electrically and flexibly. It is being replaced.
Moreover, in many devices equipped with such a motor, unnecessary rotational energy and electromagnetic energy are radiated by regenerating excessive rotational energy that is unnecessary when braking the motor to the power source, In addition, the running cost can be reduced.

FIG. 4 is a diagram illustrating a configuration example of a conventional motor driving device.
In the figure, three-phase AC power is supplied to the input of the regenerative power circuit 50. The output of the regenerative power circuit 50 is connected to the motor 70 via the motor inverter 60. The monitoring output of the motor 70 is connected to the corresponding control terminal of the motor inverter 60. The rotating shaft of the motor 70 is connected to the generator 80. The output of the generator 80 is connected to the input of the step-up inverter 82 via the electronic load device 81. The output of the step-up inverter 82 is connected to a power supply line used for supplying the three-phase AC power. Further, the corresponding output of the drive control unit 83 is connected to the control terminals of the motor inverter 60 and the electronic load 81.

  The regenerative power supply circuit 50 includes a control unit 51 and transistors 52-11, 52-12, 52-21, 52-22, 52-31, 52 that operate as three-phase full-wave rectification circuits under the control unit 51. -32 and a capacitor 53 are provided. Further, the regenerative power supply circuit 50 includes diodes 54-11, 54-12, 54-21, 54-22, 54-31, 54-32, and these diodes 54-11, 54-12, 54-. The cathodes and anodes of 21, 54-22, 54-31, 54-32 are the individual collectors and emitters of transistors 52-11, 52-12, 52-21, 52-22, 52-31, 52-32, respectively. And connected to.

  In the motor inverter 60, the collectors of the transistors 61-11, 61-21 and 61-31 are connected to the anode output of the regenerative power supply circuit 50. To the cathode output of the regenerative power supply circuit 50, the emitters of the transistors 61-12, 61-22, 61-32 are connected. The corresponding outputs of the control unit 62 are connected to the bases of these transistors 61-11, 61-12, 61-21, 61-22, 61-31, 61-32. The emitter of the transistor 61-11 and the collector of the transistor 61-12 are connected to the first input terminal of the motor 70. The emitter of the transistor 61-21 and the collector of the transistor 61-22 are connected to the second input terminal of the motor 70. The emitter of the transistor 61-31 and the collector of the transistor 61-32 are connected to the third input terminal of the motor 70. The monitoring output of the motor 70 is connected to the control input of the control unit 62 described above.

  In the motor driving device having such a configuration, the control unit 51 synchronizes with the above-described three-phase AC power, the pair of transistors 52-11 and 52-12, the pair of transistors 52-21 and 52-22, The current flow angles between the pair of transistors 52-31 and 52-32 are set to different angles by 120 degrees. Therefore, these transistors 52-11, 52-12, 52-21, 52-22, 52-31, 52-32 function as a three-phase full-wave rectifier circuit. The DC power obtained by such three-phase full-wave rectification is smoothed by the capacitor 53 and further supplied to the motor inverter 60.

  In the motor inverter 60, the control unit 62 monitors the rotation angle of the motor 70 detected by a resolver (not shown) built in the motor 70. Further, the control unit 62 uses two transistors (transistors 61-11 and 61-21) suitable for the motor 70 to continue to rotate as an AC motor based on the instruction given by the drive control unit 83 and the rotation angle. , 61-31 and any one of transistors 61-12, 61-22, 61-32) are sequentially selected and set to the on state. The instruction given by the drive control unit 83 includes, for example, the rotation speed of the motor 70 and the degree of overload.

The generator 80 generates electric power by driving the motor 70 by the motor inverter 60 in this way, and generates, for example, single-phase AC power.
Further, the drive control unit 83 identifies a period during which the motor 70 is braked while outputting the above-described instruction. Further, the drive control unit 83 is a control signal whose logical value is “1” during a period in which the rotation speed of the motor 70 is maintained or is changed to a higher value (hereinafter referred to as “non-regenerative period”). Is output. The electronic load device 81 terminates the output of the generator 80 according to the control signal of the logical value (= 1), and cancels the delivery of the AC power generated by the generator 80 to the boost inverter 82.

  However, during a period in which the rotation speed of the motor 70 is changed to a smaller value (hereinafter referred to as “regeneration period”), the drive control unit 83 sets the logical value of the control signal described above to “0”. The electronic load device 81 delivers the AC power generated by the generator 80 to the boost inverter 82 in response to the control signal having such a logical value (= 0). The step-up inverter 82 generates AC power (hereinafter referred to as “regenerative AC power”) different from the AC power by subjecting the AC power delivered in this way to voltage, phase, number of phases, and other conversions. . Further, the boost inverter 82 regenerates the regenerative AC power for both or one of the power source used to supply the three-phase AC power described above and the output of the regenerative power circuit 50.

Note that the regeneration of the line AC power with respect to the output of the regenerative power supply circuit 50 is based on the phase of the line AC power, as shown by a dotted line or a broken line in FIG. 4, for example, diodes 54-11, 54-21, This is realized by a current path formed between any one of 54-31 and one of the diodes 54-12, 54-22, 54-32 and the capacitor 53.
That is, in the motor drive device described above, the motor 70 is driven via the regenerative power supply circuit 50 and the motor inverter 60 under the control of the drive control unit 83. Further, during the regeneration period, surplus rotational energy of the motor 70 is converted into the regenerative AC power described above and regenerated.

Therefore, the motor 70 is driven efficiently, and the cost of the load test for the motor inverter 60 and the motor 70 can be kept low as well as the motor 70.
As a prior art related to the present invention, for example, as disclosed in Patent Document 1 described later, “a test belt 23 wound between a drive side test pulley 21 and a load side test pulley 22” is shown. And a load motor 41 comprising a non-commutator motor is connected to the load-side test pulley 22 and has a power regeneration converter 69 that takes out the electric power generated by the load motor 41 and returns it to the load-side power line 64. There is a belt running test machine.
JP-A-8-43255

Incidentally, in the above-described conventional example, the AC power generated by the generator 80 is once converted into DC power, and further converted into AC power by the boost inverter 82 and regenerated. Therefore, the circuit scale is large and the regeneration efficiency is not always sufficiently high.
It is an object of the present invention to provide a motor drive device, a load test support device, and a load test device that can be reduced in cost and size in accordance with improvement in regeneration efficiency.

In the motor drive device according to the first aspect, the power conversion means converts AC power into DC power. The motor driving means drives the AC motor with the DC power. The power generation means is driven by the AC motor to generate power. The DC regeneration means regenerates the electric power obtained by the power generation between the power conversion means and the motor driving means.
That is, the surplus rotational energy corresponding to the decrease in the rotational speed of the AC motor is converted into electric power by the power generation means, and then converted into AC power as in the conventional example without changing to DC power, the power conversion means and the motor. It is regenerated between stages with the drive means.

Therefore, the efficiency of regeneration is increased, and the configuration is simplified and the reliability is improved.
According to a second aspect of the present invention, in the motor driving device according to the first aspect, the power storage means regenerates excess electric power that is regenerated by the DC regeneration means and is not consumed by the motor driving means between the stages. accumulate.

That is, even if the excessive rotational energy generated by reducing the rotational speed of the AC motor increases or decreases extensively, the excessive rotational energy is converted into the aforementioned DC power and stored in the power storage means. .
Therefore, even if the rotational speed of the AC motor is drastically reduced, the regeneration efficiency is maintained high.

According to a third aspect of the present invention, in the motor driving device according to the first or second aspect, the power conversion means is configured as a bidirectional power supply device.
That is, of the DC power regenerated by the DC regeneration means between the power conversion means and the motor driving means, the surplus that is not used for further driving of the AC motor is supplied to the bidirectional power supply device. Regenerated against the source.

Therefore, the surplus rotational energy that has increased drastically and greatly in accordance with the change in the rotational speed of the AC motor can be stably regenerated as electric power even if a power storage device is not provided as in the motor drive device according to claim 2. Is done.
The motor driving device according to claim 4, wherein the motor driving means supplies AC power supplied to the AC motor to the AC motor. Is set to a value that provides a predetermined output.

That is, the output of the AC motor is set to a value suitable for the operation and load conditions of the AC motor.
Therefore, even if these operation and load conditions change in various ways, it is possible to drive the AC motor and to reuse excess rotational energy of the AC motor.
According to a fifth aspect of the present invention, in the motor drive device according to any one of the first to fourth aspects, the power generation means is configured as a DC generator.

That is, surplus rotational energy of the AC motor is directly converted into DC power by the power generation means and then regenerated between the power conversion means and the motor drive means by the DC regeneration means.
Therefore, the motor drive device according to the present invention achieves the same effects as the motor drive device according to claims 1 to 4 even when the power generation means is configured as a DC generator.

According to a sixth aspect of the present invention, the additional test support device includes the motor driving device according to any one of the first to fifth aspects. In addition, the test control means includes AC power supplied to the AC motor by the motor driving means to a value suitable for a load test of all or a part of the AC motor, the motor driving means, and the power generation means. Set.
That is, the AC motor is driven with AC power suitable for the load test.

Therefore, the load test conditions for the AC motor, the motor driving means, and the power generation means are ensured accurately and stably.
A load test apparatus according to a seventh aspect includes the load test support apparatus according to the sixth aspect. The determining means determines whether or not all or a part of operating conditions of the AC motor, the motor driving means, and the power generating means satisfy a predetermined standard.

In other words, any load test of the AC motor, the motor driving means, and the power generation means is automatically performed by the discrimination means.
Therefore, in an apparatus or system provided with any of the AC motor, the motor driving means, and the power generation means subjected to the load test by the load test apparatus according to the present invention, the performance and reliability can be improved at low cost.

As described above, according to the present invention, surplus rotational energy corresponding to the time when the rotational speed of the motor is reduced is regenerated as DC power by a small-scale hardware compared to the conventional example.
Therefore, in the apparatus and system to which the present invention is applied, the motor drive means, the AC motor, and the power generation means are operated and tested in comparison with the case where such excessive rotational energy is unnecessarily consumed as heat and other energy. The running cost is kept low and the reliability is improved without damaging the conditions.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a first embodiment of the present invention.
In contrast to the conventional example shown in FIG. 4, the configuration of the present embodiment is not provided with the boost converter 82, but is provided with the boost converter 10 instead of the electronic load device 81, and the output of the boost converter 10 is It is in the point connected between the stage of the regenerative power supply circuit 50 and the motor inverter 60.

  In boost converter 10, capacitor 11 that terminates the output of generator 80 is arranged in the first stage, and one terminal of inductor 12 is connected to capacitor 11. The other terminal of the inductor 12 is connected to the collector of the transistor 13 and the anode of the diode 14. The output of the drive control unit 83 is connected to the base of the transistor 13, and the emitter of the transistor 13 is grounded. The cathode of the diode 14 is grounded via the capacitor 15 and is connected between the stage of the regenerative power supply circuit 50 and the motor inverter 60.

The operation of the first embodiment of the present invention will be described below with reference to FIG.
The feature of the present embodiment resides in the operation of the step-up inverter 10 performed as described later in the aforementioned non-regenerative period and regenerative period. In the following description, since the operation of each part similarly provided in the conventional example shown in FIG. 4 is basically the same, the description thereof is omitted here.
During the non-regenerative period, the drive control unit 83 outputs a control signal whose logical value is “1”, as in the conventional example.

In boost converter 10, transistor 13 is turned on in response to such a control signal having a logical value (= 1). Therefore, the AC power generated by the generator 80 during the non-regenerative period is not transmitted to the diode 14 because it is terminated not only by the capacitor 11 but also by the cascaded inductor 12 and transistor 13.
In the regeneration period, the drive control unit 83 sets the logical value of the control signal described above to “0”, as in the conventional example.

  In step-up converter 10, transistor 13 is turned off in response to a control signal having a logical value (= 0). Therefore, the AC power generated by the generator 80 during the regeneration period is rectified by the diode 14 and smoothed by the capacitor 15 to be converted into DC power having a predetermined voltage. Boost converter 10 is configured in advance as a circuit of a suitable specification and method for the voltage of AC power generated by generator 80.

Therefore, the voltage of the DC power output by boost converter 10 is regenerated between the stages at a voltage higher than the potential between the stages of regenerative power supply circuit 50 and motor inverter 60 described above in the non-regenerative period.
That is, the excess rotational energy of the motor 70 corresponding to the decrease in the rotational speed of the motor 70 is converted into AC power by the generator 80, and then the stage between the regenerative power circuit 50 and the motor inverter 60 by the boost converter 10. In between, it is directly regenerated as DC power.

As described above, according to the present embodiment, the step-up inverter 82 shown in FIG. 4 is configured without being provided, so that the regeneration efficiency can be improved and the circuit scale can be reduced and the reliability can be improved compared to the conventional example. Improvement is achieved.
In the present embodiment, when it is required that a large amount of surplus electric power generated by the rotational speed of the motor 70 be rapidly regenerated and reused, for example, the capacitor 53 A battery whose electrostatic capacity is set sufficiently large in advance or connected in parallel to the capacitor 53 may be provided.

FIG. 2 is a diagram showing a second embodiment of the present invention.
The difference between the present embodiment and the first embodiment described above is that a bidirectional power supply circuit 30 is provided instead of the regenerative power supply circuit 50.
The operation of the second embodiment of the present invention will be described below with reference to FIG.
The bidirectional power supply circuit 30 converts the three-phase AC power into DC power and delivers it to the motor inverter 60 in the same manner as the regenerative power supply circuit 50 shown in FIG. However, as for the surplus DC power that is not consumed by the motor inverter 60, the bidirectional power supply circuit 30 conversely regenerates the power supply line described above by converting it into three-phase AC power.

Therefore, according to the present embodiment, as described above, the capacitance of the capacitor 53 is set to be sufficiently large in advance, or even if a battery is not added in parallel to the capacitor 53, as in the conventional example, 3 Regeneration of the power supply line that supplies the AC power of the phase is realized.
In the first and second embodiments described above, the rotation speed of the motor 70 during the non-regeneration period is maintained at a specified value.

However, the present invention is not limited to such a configuration. For example, the present invention can be applied even when the rotational speed of the motor 70 is updated to a large value stepwise during the non-regenerative period.
FIG. 3 is a diagram showing a third embodiment of the present invention.
The difference between the present embodiment and the first embodiment described above is that a test control unit 40 linked to the drive control unit 83 is provided, and the test control unit 40 is shown in the figure added to the motor inverter 60. The output of the additional circuit which is not performed and the sensors (none of which are shown) added to the motor 70 and the generator 80 are connected.

The operation of the third embodiment of the present invention will be described below with reference to FIG.
The additional circuit added to the motor inverter 60 includes, for example, the amplitude, phase, and waveform of the current that the motor inverter 60 supplies to the motor 70 through three power lines as power, and these three power lines. The amplitude and waveform of the voltage applied to the motor 70 are detected.

The sensor added to the motor 70 detects, for example, heat, vibration, sound, electromagnetic interference noise, and the like generated by the motor 70 in accordance with the rotational speed of the motor 70.
The sensor added to the generator 80 detects, for example, heat, vibration, sound, electromagnetic interference noise, etc. generated in the generator 80 in accordance with the rotational speed and electromotive force of the generator 80.
The test control unit 40 is linked with the drive control unit 83 based on conditions and schedules on which all or a part of load tests of the motor inverter 60, the motor 70, and the generator 80 are to be performed. The motor 70 is driven.

Further, the test control unit 40 records and monitors the individual items detected by the additional circuits and sensors described above in the process in which the motor 70 is driven based on the above-described conditions and schedules. It is determined whether or not the process of change satisfies a specified standard, and the result of each determination is output.
Further, the motor 70 is driven based on a desired condition and schedule, and surplus rotational energy generated in response to a decrease in the rotational speed of the motor 70 is suppressed from being radiated to the outside as heat or noise.

Therefore, according to the present embodiment, any load test of the motor inverter 60, the motor 70, and the generator 80 can be realized at low cost with high accuracy.
In the present embodiment, the regenerative power supply circuit 50 is disposed in front of the motor inverter 60.
However, such a regenerative power supply circuit 50 may be replaced with, for example, the bidirectional power supply circuit 30 as in the above-described second embodiment.

In the present embodiment, the items detected by the above-described additional circuits and sensors and recorded, monitored and discriminated by the test control unit 40 are not limited to the items described above, and may be any items. .
Further, in each of the above-described embodiments, the generator 80 that is a single-phase AC generator is driven by the motor 70.

However, the present invention is not limited to such a configuration, and the generator 80 may be configured as a three-phase AC generator.
Further, the generator 80 is configured as a DC generator, and instead of the boost converter 10, for example, a direct current having a voltage that can be regenerated between the stages of the regenerative power supply circuit 50 (bidirectional power supply circuit 30) and the motor inverter 60. A voltage conversion circuit for obtaining power may be provided.

  Furthermore, the present invention is not limited to the above-described embodiments, and various embodiments are possible within the scope of the present invention, and any modification may be made to all or part of the constituent devices.

It is a figure which shows 1st embodiment of this invention. It is a figure which shows 2nd embodiment of this invention. It is a figure which shows 3rd embodiment of this invention. It is a figure which shows the structural example of the conventional motor drive device.

Explanation of symbols

10 Boost Converter 11, 15, 53 Capacitor 12 Inductor 13, 52, 61 Transistor 14, 54 Diode 30 Bidirectional Power Supply Circuit 40 Test Control Unit 50 Regenerative Power Supply Circuit 51, 62 Control Unit 60 Motor Inverter 70 Motor 80 Generator 81 Electronic Load 82 Boost Inverter 83 Drive Control Unit

Claims (7)

Power conversion means for converting AC power into DC power;
Motor driving means for driving an AC motor with the DC power;
Power generating means driven by the AC motor to generate power;
A motor drive device comprising: DC regeneration means for regenerating power obtained by the power generation between stages of the power conversion means and the motor drive means. The motor drive device according to claim 1,
A motor drive device comprising: a power storage means for accumulating surplus power regenerated by the DC regeneration means and not consumed by the motor drive means between the stages. In the motor drive device according to claim 1 or 2,
The power conversion means includes
A motor drive device characterized by being configured as a bidirectional power supply device. In the motor drive unit according to any one of claims 1 to 3,
The motor driving means is
The motor drive device characterized in that the AC power supplied to the AC motor is set to a value at which a predetermined output can be obtained by the AC motor. In the motor drive device according to any one of claims 1 to 4,
The power generation means includes
A motor drive device characterized by being configured as a DC generator. The motor drive device according to any one of claims 1 to 5,
Test control means for setting the AC power supplied to the AC motor by the motor driving means to a value suitable for a load test of all or part of the AC motor, the motor driving means, and the power generation means; A load test support device characterized by comprising: The load test support device according to claim 6,
A load testing apparatus comprising: a determination unit that determines whether or not all or a part of operating states of the AC motor, the motor driving unit, and the power generation unit satisfy a predetermined standard. .

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