JP2015195666A - Inverter testing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inverter testing device capable of easily testing an inverter to be tested, by generating and giving a load simulating an SR motor.SOLUTION: The inverter testing device includes: a coil 31 to which an output line 91 from an inverter 9 to be tested is connected; inductance change means 3 for changing inductance L1 of the coil 31; and control means 4 for controlling the inductance change means 3. The control means 4 further includes a simulation angle detection signal generating part 43 which generates a simulation angle detection signal Sθ simulating a detection signal for a rotational angle of the motor, and the inductance change means 3 is controlled so as to change the inductance L1 of the coil 31 on the basis of the simulation angle detection signal Sθ generated by the simulation angle detection signal generating part 43.

Description

  The present invention relates to an inverter test apparatus for testing an inverter by generating a load that simulates a motor.

  In order to easily perform a test of an inverter that drives a motor, an inverter testing apparatus that can apply a load simulating a motor to the inverter without actually connecting the motor has been proposed.

  For example, the inverter test apparatus shown in Patent Document 1 is a load that simulates a permanent magnet motor (PM motor) that is connected to an inverter under test to be tested, and is driven by a three-phase AC power source with respect to the inverter under test. It is possible to give.

  Such an inverter test apparatus is generally configured as shown in FIG. That is, the inverter test apparatus 501 is connected to the output line 592 of the inverter under test 509 via the reactor 593. The inverter test apparatus 501 can detect the voltage with the voltage detector 594 upstream of the reactor 593 (the inverter under test 509 side), and can detect the current flowing through the output line 592 with the current detector 595. It has become. Further, the inverter test apparatus 501 sets the characteristics of the simulation target motor as an internal constant, and controls the detected current value and the internal constant to be a voltage derived from the motor voltage equation. . Further, a simulated angle detection signal Sθ simulating a signal from the motor angle detector is output and output to the inverter under test 509. In this way, the inverter under test 509 is given a load simulating a motor, such as performing feedback control using the current value detected by the current detector 596 in the output line 592 and the angle detector simulation signal Sθ. However, it is possible to perform the same control as when the motor is rotated.

  By the way, in recent years, a switched reluctance motor (SR motor) whose principle is different from that of the permanent magnet motor and the induction motor generally used therewith has been attracting attention. As schematically shown in FIG. 7, the SR motor includes a stator 621 with a saliency rotor 611 and a coil 623, and the salient poles 622 of the stator 621 and the salient poles 612 of the rotor 611 are aligned to face each other. In the salient pole symmetry state, the magnetic impedance is reduced and the inductance of the coil 623 is maximized. Therefore, when an excitation current is supplied from the inverter 609 to the coil 623 of the salient pole 622 that is in a salient pole asymmetrical state in which the magnetic flux does not easily flow, the rotor 611 rotates so as to be in a salient pole symmetrical state where the magnetic flux is most likely to flow. The rotor 611 can be rotated by sequentially switching the coil 623 that supplies the excitation current from the inverter 609 based on the rotation angle of the rotor 611.

JP 2003-153547 A

  In parallel with the development of the SR motor, an inverter used to drive the motor is also being developed. In order to advance the inverter test efficiently, it is preferable to use the inverter test apparatus as described above without using an actual motor.

  However, since an SR motor is driven by sequentially applying voltages to a plurality of stator coils, unlike an SR motor that applies a three-phase AC voltage, a load that simulates a motor using a conventional inverter test apparatus. Can not cause.

  In the SR motor, as schematically shown in FIG. 8A, the relative positional relationship between the salient pole 612 on the rotor 611 side and the salient pole 622 on the stator 621 side is changed by the rotation of the rotor 611. Thereby, as shown in FIG.8 (b), the inductance L in the coil 623 changes. Specifically, when the salient poles 612 and 622 are separated from each other, the inductance L is small, and when the salient poles 612 and 622 are opposed to each other, the inductance L is greatest, and the rotor 611 rotates. Thus, the inductance L periodically repeats increasing and decreasing.

  Therefore, even while the voltage is supplied from the inverter 609 to drive the SR motor, a constant current corresponding to the voltage is not supplied to the coil 623 and depends on the rotation angle of the rotor 611. The current value changes under the influence of the change in inductance L, and a load corresponding to the current value is given to the inverter 609.

  In order to simply simulate the characteristics of such an SR motor, it is conceivable that the inverter test apparatus is configured as shown in FIG. FIG. 9 schematically shows only one phase extracted. An inverter test apparatus 701 is connected to the output line 792 of the inverter under test 709 via a reactor 793. The inverter test apparatus 701 can change the voltage V0 of the internal power supply 794. Yes.

In this way, the relationship between the voltage V1 upstream of the reactor, the voltage V2 downstream, the current I flowing through the reactor 793, and the inductance L of the reactor 793 is expressed by the following equation.
dI / dt = (V1-V2) / L (Formula 1)
Here, t represents time, and dI / dt represents the rate of change of current.

  That is, if the voltage V0 of the internal power supply 794 of the inverter test apparatus 701 is changed according to the output voltage V1 from the inverter under test 709 and the voltage V2 downstream of the reactor 793 is changed, the SR motor is rotated. Similarly, it is considered that the current I can be changed.

  However, in the case of a configuration such as the inverter test apparatus 701, if the internal element is switched in order to change the voltage of the internal power supply 794, the dI / dt changes accordingly, and smoothing is performed. It will be necessary. For this reason, it is difficult to cope with a steep change, and it is impossible to accurately simulate the rise and fall of the current, and there is a possibility that the response sufficient for the test of the inverter under test 709 may not be obtained.

  An object of the present invention is to effectively solve such problems. Specifically, the present invention can generate and give a load having characteristics excellent in high-speed response that simulates an SR motor, and can be easily applied. An object of the present invention is to provide an inverter test apparatus capable of testing a test inverter.

  In order to achieve this object, the present invention takes the following measures.

  That is, the inverter testing apparatus of the present invention includes a coil to which an output line from the inverter under test is connected, an inductance changing means for changing the inductance of the coil, and a control means for controlling the inductance changing means. The control means further includes a simulated angle detection signal generation unit that generates a simulated angle detection signal that simulates a detection signal of the rotation angle of the motor, and based on the simulated angle detection signal by the simulated angle detection signal generation unit The inductance changing means is controlled to change the inductance of the coil.

  With this configuration, the control unit generates a simulated angle detection signal corresponding to the rotation angle of the motor in the simulated angle detection signal generation unit, and controls the inductance changing unit based on the simulated angle detection signal. The inductance of the coil to which the output line from the inverter under test is connected is changed to generate a load with excellent high-speed response characteristics that simulates an SR motor that changes in inductance with changes in the rotation angle. Can be given to the test inverter. Therefore, it is possible to easily test the inverter that drives the SR motor.

  In order to more accurately simulate the SR motor characteristics and realize the same test as when using an actual motor, the control means includes an inductance characteristic associated with the rotation angle of the rotor in the simulated motor. Is further provided, and the inductance of the coil is changed based on the inductance characteristic stored in the storage unit and the simulated angle detection signal from the simulated angle detection signal generation unit. Is preferred.

  In order to make it possible to apply a load having the same characteristics as the SR motor with a simple control, the coil is configured as a first coil wound around an iron core, and the inductance changing means includes a second coil. A coil and a current supply unit that supplies the second coil. The amount of current supplied from the current supply unit to the second coil is changed by the control unit, and the second coil It is preferable that the magnetic flux generated is changed to change the magnetic flux passing through the iron core to change the inductance of the first coil.

  In order to improve control accuracy and efficiency by reducing leakage magnetic flux, the second coil is configured to wind the same iron core around which the first coil is wound. Is preferred.

  In order to further reduce the leakage magnetic flux and further improve the efficiency, it is more preferable to configure the iron core in an annular shape.

  In order to facilitate the configuration and assembly of the circuit and to reduce the leakage magnetic flux and improve the accuracy of control, the second coil is close to or adjacent to the iron core around which the first coil is wound. It is preferable that the different iron cores arranged as described above are wound.

  In order to control the inverter under test and the inverter test apparatus synchronously and to perform an accurate test that is closer to the actual motor operating condition, the inverter under test is provided with an angle detection signal from the motor. It is preferable to supply a voltage to the motor on the basis of the above, and to output a simulated angle detection signal from the simulated angle detection signal generation unit instead of the angle detection signal to a connected inverter under test. It is.

  According to the present invention described above, it is possible to provide an inverter testing apparatus that can generate a load having characteristics excellent in high-speed response that simulates an SR motor and can easily test an inverter under test. It becomes possible.

The circuit block diagram which shows the inverter test apparatus which concerns on one Embodiment of this invention. FIG. 3 is a block diagram schematically showing a part of the inverter test apparatus. Explanatory drawing which shows the view of the electric current given to a 2nd coil in the same inverter test apparatus. Explanatory drawing which shows an example of the inductance change which arises in the 1st coil in the inverter testing apparatus. Explanatory drawing which shows the modification of the same inverter test apparatus. The schematic diagram which shows the conventional inverter test apparatus. The schematic diagram which shows an example of a structure of SR motor. Explanatory drawing for demonstrating the characteristic of SR motor. The schematic diagram which shows the example which comprised the inverter test apparatus which simulated SR motor based on the conventional inverter test apparatus.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The inverter test apparatus of this embodiment is configured as shown in the circuit configuration diagram of FIG. The inverter test apparatus 1 is used for testing an inverter for driving an SR motor, and is connected to an inverter under test 9 to be tested, and is an SR to be simulated with respect to the inverter under test 9. A load corresponding to the characteristics of the motor is applied. In the present embodiment, a case where the inverter to be tested outputs a three-phase voltage for driving a three-phase SR motor is taken as an example.

  Both the inverter test apparatus 1 and the inverter under test 9 operate based on electric power obtained from the commercial AC power supply 61. The AC voltage from the commercial AC power supply 61 is converted into a DC voltage by the rectifier circuit 63 via the transformer 62. The DC voltage obtained from the rectifying circuit 63 is adjusted by the voltage adjusting circuit 64 and then input to the inverter 9 to be tested. In the voltage adjusting circuit 64, by adjusting the input voltage of the inverter 9 to be tested, it is possible to test the inverter 9 to be tested while simulating the case where the power supply voltage is changed. The inverter under test 9 switches the switching elements provided inside based on the electric power input from the voltage adjustment circuit 64, so that the U-phase / V-phase / W-phase is output from the output line 91 (91 U, 91 V, 91 W). Can output a three-phase voltage corresponding to.

  The inverter testing apparatus 1 is for testing such an inverter 9 to be tested. The inverter testing apparatus 1 mainly includes the control means 4, the coils 31 to 31 as three first coils, and the inductances of the coils 31 to 31. It comprises inductance changing means 3 to 3 for changing L1 (see FIG. 2). Each inductance changing unit 3 includes an iron core 33, a coil 32 as a second coil, and a current supply unit 21, as will be described in detail later. Furthermore, the inverter 2 for simulated circuits is comprised by the three electric current supply parts 21-21.

  A DC voltage obtained from the rectifier circuit 63 is supplied to the simulation circuit inverter 2 in parallel with the voltage regulator circuit 64. The current I2 corresponding to each of the three phases is supplied from the three current supply units 21 constituting the simulated circuit inverter 2. Each current supply unit 21 can supply the current I2 based on the electric power obtained from the rectifier circuit 63 by switching a plurality of switching elements provided therein in accordance with the current command Ic from the control means 4.

  The three coils 31 to 31 described above are respectively connected to a part of the corresponding annular iron core 33, and the output lines 91 (91U, 91V, 91W) of the inverter 9 to be tested are respectively connected. Therefore, when the current I1 is supplied from the inverter 9 under test through the output lines 91 (91U, 91V, 91W), the magnetic flux φ1 (see FIG. 2) is generated in each iron core 33 by each coil 31.

  A coil 32 as a second coil is wound around each iron core 33 together with a coil 31 that is a first coil, and the current supply unit 21 that constitutes the simulated circuit inverter 2 is provided in the coil 32. Even when the current I2 is supplied from the current supply unit 21 to each coil 32, the magnetic flux φ2 (see FIG. 2) can be generated in each iron core 33. The iron core 33 and the coils 31 and 32 have the same structure as a so-called transformer, and can be configured using such a transformer.

  Further, in this embodiment, the inverter under test 9 and the control means 4 are connected to the host controller 7. The host controller 7 can cause the inverter 9 to be tested and the control means 4 to operate based on the conditions stored therein.

  FIG. 2 is a block diagram schematically showing the inverter test apparatus 1 described above, and shows only one phase extracted and simplified.

  As described above, the output line 91 from the inverter 9 to be tested is connected to the coil 31 wound around the annular core 33, and the power supply unit 21 constituting the simulated circuit inverter 2 is wound around the same core 33. Connected to the coil 32. The control means 4 operates based on the command signal Sg given from the host controller 7, and similarly, the inverter under test 9 operates according to the conditions given by the host controller 7 while transmitting information to and from the host controller 7. .

  The control unit 4 includes a current command generation unit 41, a storage unit 42, and a simulated angle detection signal generation unit 43. Here, the control means 4 is constituted by a normal microprocessor or the like having a CPU, a memory, and an interface. The memory stores programs necessary for processing in advance, and the CPU sequentially stores necessary programs. It is taken out and executed, and realizes a predetermined function in cooperation with peripheral hardware resources.

  The storage unit 42 stores an inductance characteristic L (θ) input from the outside in advance through an input unit (not shown). The inductance characteristic L (θ) indicates the characteristic of the motor to be simulated, and is stored as data of the inductance L associated with the rotor angle θ (see FIG. 8). In the present embodiment, the stored inductance characteristic L (θ) is used as map data obtained by collecting discrete data and collecting them in a tabular form, and the data is used after linear interpolation. It should be noted that such data can be used in the same manner even if it is stored as a mathematical expression.

  The simulated angle detection signal generation unit 43 generates and outputs a simulated angle detection signal Sθ in accordance with the command signal Sg from the host controller 7. In general, an SR motor is provided with an angle detector such as a resolver, and an inverter switches a coil for supplying a current based on an angle detection signal from the angle detector. Therefore, in this embodiment, in order to operate the inverter 9 under test, a simulated angle detection signal Sθ imitating the signal from the resolver is generated and output to the inverter 9 under test. The timing of supplying and stopping the supply of the current I1 from the output line 91 is changed according to the angle detection signal Sθ. By doing so, the inverter 9 to be tested and the control means 4 can operate synchronously, and a more accurate test can be performed.

  The current command generation unit 41 refers to the inductance angle L (θ) stored in the storage unit 42 according to the simulation angle detection signal Sθ generated by the simulation angle detection signal generation unit 43, and the current I2 passed through the coil 32 To generate a current command Ic to be supplied to the current supply unit 21. The current supply unit 21 supplies the current I2 to the coil 32 in accordance with the current command Ic given from the current command generation unit 41. The current I2 applied to the coil 32 is detected by the current detector 22, and the detected current value Id is input to the current command generator 41. The current command generator 41 can perform more accurate control by feeding back the detected current value Id and correcting the current command Ic.

  By supplying the current I2 from the current supply unit 21 to the coil 32, the magnetic flux φ2 can be generated in the iron core 33 around which the coil 32 is wound. By doing so, the inductance L1 of the coil 31 wound around the same iron core 33 can be changed. Furthermore, since the iron core 33 is formed in an annular shape, the leakage flux can be reduced to increase efficiency, and the magnetic flux inside the iron core 33 can be changed more greatly with a small current I2 to improve control accuracy. It is also possible to plan.

  As described above, the control unit 4 gives the current command Ic from the current command generation unit 41 to the current supply unit 21, thereby causing the current supply unit 21 to supply the corresponding current I <b> 2 to the coil 32. That is, the control unit 4 controls the inductance changing unit 3.

Here, the concept of the current I2 supplied from the current supply unit 21 will be described in detail. First, in order to make the inductance L1 of the coil 31 the same as the inductance characteristic L (θ) depending on the rotor angle θ, the following relationship is obtained.
L1 = L (θ) (Formula 2)

The relationship between the current I1 flowing through the coil 31 and the voltage V1 applied to both ends of the coil 31 is expressed as follows.
V = (dI1 / dt) · L (θ) (Formula 3)

Furthermore, when the mutual inductance M by the coil 31 and the coil 32 is used, the following relationship is derived.
(DI1 / dt) + (dI2 / dt) = V / M (Formula 4)

From Equation 3 and Equation 4, the following relationship is obtained.
(DI2 / dt) = V / MV−L (θ) (Formula 5)

  That is, it can be said that the inductance characteristic L (θ) can be simulated by changing the current I2 supplied to the coil 32 using the relationship of Formula 5.

  In the inverter testing apparatus 1 configured as described above, a load that simulates the characteristics of the SR motor can be applied to the inverter under test 9 as follows. Hereinafter, description will be made with reference to FIG. The constituent elements of the SR motor to be simulated are the same as those described with reference to FIGS.

  FIG. 3A schematically shows that the inductance L of the coil 623 provided in the stator 621 changes according to the rotation of the rotor 611. That is, when the salient pole 612 of the rotor 611 is located sufficiently away from the salient pole 622 of the stator 621 (position P1 in the figure), the inductance L is small, and the rotor 611 is connected to the salient pole 622 of the stator 621. In the process of approaching the salient poles 612, the inductance L gradually increases, and when the salient poles 622, 612 are at positions facing each other (position P2 in the figure), the inductance L is maximized. Further, in the process in which the rotor 611 rotates and the salient pole 612 of the rotor 611 is separated from the salient pole 622 of the stator 621, the inductance L gradually decreases, and the positions where both salient poles 622 and 612 are sufficiently separated (see FIG. In the case of the position P3 in the middle), the inductance L is minimized.

  When controlling the operation of such an SR motor, the following two control methods are conceivable.

  As a first control method, as shown in FIG. 3B, there is a case where control during powering is performed in which a driving force is applied to the SR motor in the rotational direction of the rotor 611. At this time, the switch of the inverter 9 is switched from the P1 position where the salient pole 612 of the rotor 611 is sufficiently separated from the salient pole 622 of the stator 621 to the P2 position where the salient poles 612 and 622 face each other. The voltage V is applied to the coil 623 in the ON state. By doing so, the current I1 (stator current in the figure) flows through the coil 623 until the salient poles 612 and 622 face each other, and the salient pole 612 of the rotor 611 moves toward the salient pole 622 of the stator 621. A rotational driving force is generated by the suction. At this time, since the inductance L of the coil 623 gradually increases as the salient poles 612 and 622 approach each other, the rate of change of the current I1, that is, the slope of the current I1 gradually decreases.

  Then, during the period from the P2 position where the salient poles 612 and 622 face each other to the P3 position where both salient poles 612 and 622 are sufficiently separated, the switch of the inverter 9 is turned off to supply voltage to the coil 623. Stop. By doing so, the current I1 flowing through the coil 623 is reduced while the salient poles 612 and 622 are separated from each other, so that the salient pole 612 of the rotor 611 is not attracted by the salient pole 62 of the stator 621. To do. In this case, a current is normally supplied to another coil 623 (not shown).

  As a second control method, as shown in FIG. 3C, there is a case where control at the time of regeneration in which a braking force is applied to the SR motor in a direction opposite to the 66 rotation direction of the rotor may be performed. At this time, the inverter 9 is switched off until the salient pole 612 of the rotor 611 reaches the P2 position where the salient poles 612 and 622 face each other from the P1 position sufficiently separated from the salient pole 622 of the stator 621. In this state, no voltage is supplied to the coil 623.

  Then, from the position P2 where the salient poles 612 and 622 face each other to the position P3 where both the salient poles 612 and 622 are sufficiently separated from each other, the switch of the inverter 9 is turned on (ON) to the coil 623. Supply voltage V. As a result, while the salient poles 612 and 622 are separated from each other, a current I1 (stator current in the drawing) flows through the coil 623, and the salient pole 612 of the rotor 611 faces the salient pole 622 of the stator 621. As a result, the braking force is generated. At this time, since the salient poles 612 and 622 are separated from each other, the inductance L of the coil 623 gradually decreases, so that the rate of change of the current I1, that is, the slope of the current I1 gradually increases.

  As described above, the SR motor is roughly divided into two types of control during power running and regeneration. During such control, the current I1 applied to each coil 623 varies with the inductance L (θ) corresponding to the rotor angle θ.

  Therefore, in the present embodiment, the current I2 as shown in FIG. 3D is supplied to the coil 32 by performing the control based on the above-described Expression 5. That is, the current I2 is increased from the P1 position where both salient poles 612 and 622 are separated from each other to the P2 position where both salient poles 612 and 622 face each other. Then, the current I2 is decreased from the position P2 where the salient poles 612 and 622 are opposed to the position P3 that is sufficiently separated.

  When the current I2 having such a relationship is set, the inductance L1 in the coil 31 that is the first coil has characteristics as shown in FIG.

  That is, when the voltage V is supplied to the coil 31 that is the first coil and the current I1 is increasing, the current I2 is supplied to the coil 32 that is the second coil and the magnetic flux generated by the coil 31 is generated. When the magnetic flux φ2 in the same direction as φ1 is generated, the magnetic flux change due to the coil 31 is apparently increased and the inductance L1 is increased. Furthermore, when the voltage I is supplied to the coil 31 that is the first coil and the current I1 is increasing, the current I2 is supplied in the opposite direction to the coil 32 that is the second coil, When the magnetic flux φ2 is generated in the direction opposite to the magnetic flux φ1 generated by the coil 31, the change in magnetic flux due to the coil 31 is apparently reduced and the inductance L1 is reduced. Therefore, the inductance L1 of the coil 31 when the voltage V is supplied has the characteristic of the inductance Lon indicated by a solid line in the drawing.

  Further, when the supply of the voltage V to the coil 31 which is the first coil is stopped and the current I1 is decreasing, the current I2 is supplied to the coil 32 which is the second coil. When the magnetic flux φ2 in the same direction as the generated magnetic flux φ1 is generated, the magnetic flux change by the coil 31 is apparently reduced, and the inductance L1 is lowered. Furthermore, when the supply of the voltage V to the coil 31 that is the first coil is stopped and the current I1 is decreasing, the current I2 is applied to the coil 32 that is the second coil in the opposite direction. When the magnetic flux φ2 is generated in the opposite direction to the magnetic flux φ1 generated by the coil 31, the change in the magnetic flux due to the coil 31 is apparently increased and the inductance is increased. Therefore, the inductance L1 of the coil 31 when the supply of the voltage V is stopped has the characteristic of the inductance Loff indicated by a one-dot chain line in the drawing.

  As described above, the influence of the magnetic flux φ2 generated by passing the current I2 through the coil 32 is opposite between when the voltage V is supplied to the coil 31 and when the supply of the voltage V is stopped. However, since the influences thereof are different from each other, the inductance L1 of the coil 31 obtained by averaging both has the characteristic of the inductance Lave as shown by the broken line in the drawing.

  Therefore, as shown in FIGS. 1 and 2, the inverter 9 under test operates in accordance with the operating conditions given by the host controller 7 and outputs to the coil 31 through the output line 91. The simulated angle detection signal Sθ is generated by the simulated angle detection signal generation unit 43 in response to the command signal Sg from 7, and the simulated angle detection signal Sθ and the inductance characteristic L of the SR motor that is the simulation target stored in the storage unit 42. Based on (θ), a current command Ic is generated by the current command generation unit 41 and supplied to the current supply unit 21 to supply a current I2 corresponding to the coil 32 to generate a magnetic flux φ2 and to generate an inductance of the coil 31. Change L1. Therefore, an inductance characteristic of L (θ) similar to that of the SR motor is generated in the coil 31, and the same load as that of the SR motor to be simulated is applied to the inverter 9 to be tested. The test can be performed under the same conditions as when the motor is connected.

  As described above, the inverter testing apparatus 1 according to the present embodiment includes the coil 31 to which the output line 91 from the inverter under test 9 is connected, the inductance changing unit 3 that changes the inductance L1 of the coil 31, and the inductance changing unit. 3, and the control unit 4 further includes a simulated angle detection signal generation unit 43 that generates a simulated angle detection signal Sθ that simulates a detection signal of the rotation angle θ of the motor 601. The inductance changing means 3 is controlled to change the inductance L1 of the coil 31 based on the simulated angle detection signal Sθ by the simulated angle detection signal generator 43.

  With this configuration, the control means 4 controls the inductance changing means 3 based on the simulated angle detection signal Sθ corresponding to the rotation angle θ of the rotor 611 constituting the motor 601, so that the device under test is controlled. A load with excellent high-speed response that simulates the SR motor 601 in which the inductance L1 of the coil 31 to which the output line 91 from the inverter 9 is connected is changed and the inductance L changes with the change of the rotor angle θ is tested. It can be given to the inverter 9. Therefore, it is possible to easily test the inverter 9 that drives the SR motor 601.

  Further, the control unit 4 further includes a storage unit 42 that stores an inductance characteristic L (θ) associated with the rotation angle θ of the rotor 611 in the simulated motor 601, and the inductance characteristic L stored in the storage unit 42. Since the configuration is such that the inductance L1 of the coil 31 is changed on the basis of (θ) and the simulated angle detection signal Sθ by the simulated angle detection signal generation unit 43, the control means 4 is configured to rotate the rotation angle of the rotor 611. By accurately simulating the change in the inductance L of the coil 623 in accordance with θ, it is possible to realize a load characteristic close to that of the actual motor 601. A test can be performed.

  The coil 31 is configured as a first coil 31 wound around an iron core 33, and the inductance changing unit 3 includes a coil 32 that is a second coil and a current supply unit 21 that supplies the coil 32. The amount of current I2 supplied from the current supply unit 21 to the coil 32 is changed under the control of the control means 4, and the magnetic flux φ2 generated by the coil 32 is changed, so that the magnetic flux φ1 passing through the iron core 33 is changed and the coil is changed. Since the inductance L1 of the coil 31 is changed, the current supply unit 21 is controlled by the control means 4, thereby controlling the amount of current I2 flowing through the coil 32 and changing the magnetic flux φ1 passing through the iron core 33. Then, the inductance L1 of the coil 31 that winds the iron core 33 can be changed, and the inverter 9 to be tested connected to the coil 31 can be changed. To, it is possible to give the same load and the SR motor 601 with a simple control.

  Furthermore, since the coil 32 is configured to wind the same iron core 33 around which the coil 31 is wound, the leakage magnetic flux is reduced, and the control can be highly accurate and the efficiency can be improved. .

  In addition, since the iron core 33 is formed in an annular shape, it is possible to further reduce the leakage magnetic flux and further improve the efficiency.

  The inverter 9 under test supplies voltage to the motor 601 based on the angle detection signal from the motor 601, and a simulated angle detection signal generator for the connected inverter 9 under test instead of the angle detection signal. 43, the inverter 9 under test supplies voltage based on the simulated angle detection signal Sθ from the simulated angle detection signal generator 43, and the inverter test apparatus 1 Since the load is changed by changing the inductance L1 based on the same simulated angle detection signal Sθ, both of them are controlled in synchronization, and it is possible to perform an accurate test closer to the actual driving state of the motor 601. Become.

  The specific configuration of each unit is not limited to the above-described embodiment.

  For example, the inductance changing means 3 can be changed as shown in FIGS. 5A and 5B based on the embodiment described above. In these drawings, the same reference numerals are given to the same portions as those in the above-described embodiment, and the description thereof is omitted. Inductance changing means 103 shown in FIG. 5A is formed by forming a coil 31 and an iron core 133 around which the coil 32 is wound into a cylindrical shape. In this case, compared with the annular iron core 33 (see FIG. 2) shown in the above-described embodiment, the leakage magnetic flux is slightly increased and the efficiency is slightly decreased, but the same effect as described above can be obtained. Moreover, since the iron core 133 can be made small compared with the case where the annular iron core 33 is used, size reduction can be achieved.

  5B, the iron core 233 around which the coil 31 is wound and the iron core 234 around which the coil 32 is wound are configured separately. Although the iron cores 233 and 234 are provided separately, they are provided close to or adjacent to each other, so that the effects according to the above embodiment can be obtained. Furthermore, the coil 32 that is the second coil is configured to wind a different iron core 234 disposed adjacent to or adjacent to the iron core 233 around which the coil 31 that is the first coil is wound. Therefore, the configuration and assembly of the circuit can be facilitated, and the control can be performed with high accuracy by reducing the leakage magnetic flux.

  Furthermore, in the above-described embodiment, an example of a three-phase inverter for driving a three-phase SR motor as the inverter 9 to be tested has been described. However, the SR motor may be other than three-phase, and the principle Specifically, even a single phase can be driven. Therefore, the above-described inverter test apparatus 1 can also be configured to correspond to a single phase or a plurality of phases different from the three phases, and an inductance including the power supply unit 21, the coil 32, and the iron core 33 according to the number of phases. It is sufficient to change the number of changing means 3.

  Other configurations can be variously modified without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Inverter test apparatus 2 ... Simulated circuit inverter 3 ... Inductance change means 4 ... Control means 9 ... Inverter under test 21 ... Current supply part 31 ... Coil (1st coil)
32 ... Coil (second coil)
33, 133, 233, 234 ... iron core 42 ... storage unit 43 ... simulated angle detection signal generation unit 601 ... motor (SR motor)
611 ... Rotor 623 ... Coil I, I1, I2 ... Current L, L1 ... Inductance L (θ) ... Inductance characteristics Sθ ... Simulated angle detection signal θ ... (Rotor) rotation angle φ, φ1, φ2 ... Magnetic flux

Claims (7)

A coil to which the output line from the inverter under test is connected, an inductance changing means for changing the inductance of the coil, and a control means for controlling the inductance changing means,
The control means further includes a simulated angle detection signal generation unit that generates a simulated angle detection signal that simulates a detection signal of the rotation angle of the motor, and based on the simulated angle detection signal by the simulated angle detection signal generation unit, An inverter testing apparatus configured to control the inductance changing means to change the inductance.   The control unit further includes a storage unit that stores an inductance characteristic associated with a rotation angle of the rotor in the motor to be simulated, and the simulation is performed by the inductance characteristic stored in the storage unit and the simulation angle detection signal generation unit. 2. The inverter testing apparatus according to claim 1, wherein the inductance of the coil is changed based on an angle detection signal.   The coil is configured as a first coil wound around an iron core, and the inductance changing unit includes a second coil and a current supply unit that supplies the second coil, and the control unit The amount of current supplied from the current supply unit to the second coil is changed by the control according to the above, and the magnetic flux generated by the second coil is changed, thereby changing the magnetic flux passing through the iron core and changing the first coil. The inverter test apparatus according to claim 1, wherein the inductance of the inverter is changed.   The inverter test apparatus according to claim 1, wherein the second coil is configured to wind the same iron core around which the first coil is wound.   The inverter testing apparatus according to claim 4, wherein the iron core is formed in an annular shape.   The said 2nd coil was comprised so that the different iron core arrange | positioned adjacent to or adjacent to the iron core in which the said 1st coil was wound may be wound. The inverter test apparatus described.   The inverter under test supplies voltage to the motor based on the angle detection signal from the motor, and the simulated angle detection signal generation unit generates a simulated angle instead of the angle detection signal for the connected inverter under test. The inverter test apparatus according to claim 1, wherein the inverter test apparatus is configured to output a detection signal.

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