JP2020188531A - Motor operation system, motor, and driving method for motor - Google Patents

Abstract

To switch an electrification degree (pole number) in a motor of which the number of slots on a pole and phase basis is 2 or more.SOLUTION: In a motor 30, an average θ of mechanical phase angle differences between coils to be mechanical phase angles adjacent in phases of an m-phase coil (m is an odd integer equal to or greater than 5) satisfies the relation of θ=360°/(m*p) in a case that a parameter (p) indicating the number of sets of the m-phase coils in the motor is defined as any integer of which the value is equal to or greater than 1, and the coils of the phases are connected in a star ring shape in which the coils of phases to be separated by L*θ with a mechanical phase angle difference with respect to a value of a span L (L is a positive integer equal to or smaller than m/2) are connected. An electrification degree (h) (any integer of h≥1) is used to make an electrical phase difference δ of an electrification current between adjacent coils in the phases at mechanical phase angles satisfy δ=h*360°/m. A number (q) of slots on a pole and phase basis based on a pole number at the time of electrification degree h=1 is made lead 6≥q≥2, thereby suppressing reduction of efficiency in a case that a driver 60 switches the electrification degree.SELECTED DRAWING: Figure 13A

Description

The present disclosure relates to an electric motor operation system for operating a multi-phase electric motor, the electric motor thereof, and a method for driving the electric motor.

A multi-phase electric motor has been proposed in which the number of poles can be switched for the purpose of expanding the range of operable torque and rotation speed (see, for example, Patent Document 1). In the motor described in Patent Document 1, an attempt has been made to make the winding pitch γ smaller than the value 1 to improve the characteristics for the case where the harmonic order h of the current energized in the electric motor is the value 2.

U.S. Patent Publication No. 7,928,683

However, in Patent Document 1, only the case where the number of slots q of each pole and each phase is a value 1 is considered, and when the number of poles is switched, the characteristics of the motor may deteriorate due to the harmonic magnetic flux. Obtained.

The present disclosure can be realized as the following forms or application examples.

As an embodiment of the present disclosure, an electric motor operation system (20) including an electric motor (30) and a drive unit (60) for operating the electric motor is provided. In this motor operation system, the motor has an average θ of mechanical phase angle differences between windings having adjacent mechanical phase angles in each phase of m-phase windings (m is an odd integer of 5 or more). A variable p indicating the number of sets of m-phase windings in an electric motor is set as an arbitrary positive integer having a value of 1 or more.
θ = 360 ° / (m · p)
Satisfying the above relationship, the connection of the windings of each phase is a phase winding having a mechanical phase angle difference L · θ away from the value of span L (L is a positive integer of m / 2 or less). The number of slots q for each phase of each pole based on the number of poles when the energization order h (any integer of h ≧ 1) is 1 is 6 ≧ q ≧ 2, which is a star-shaped annular connection connecting the two. In the driving unit, the electrical phase difference δ of the current flowing between the windings having the mechanical phase angles adjacent to each other in each phase is set.
δ = h · 360 ° / m
It is possible to energize the m-phase winding so as to be. This electric motor operation system can increase the difference between the positive phase magnetic flux density and the negative phase magnetic flux density in the electric motor. Therefore, the characteristics of the electric motor can be improved as compared with the electric motor having the number of slots q = 1 for each pole and each phase.

The schematic block diagram which shows the electric motor operation system of an embodiment. Sectional view along the axial direction of the electric motor. 3-3 sectional view of the electric motor in FIG. Explanatory drawing which shows the appearance of the star-shaped annular connection of the winding of 5 phases with span L = 2. Explanatory drawing which shows the appearance of the star-shaped annular connection of the winding of 5 phases with span L = 1. The flowchart which shows the motor control routine with the pole number switching. Explanatory drawing which shows the operating area of an electric motor by switching the energization order. Explanatory drawing which illustrates the current from terminal T1. The schematic diagram which shows the relationship between the line current and the coil current in the case of 4 poles and the case of 8 poles. The graph which shows the current distribution of each phase coil in 4 poles (energization order h = 1) and 8 poles (energization order h = 2). Explanatory drawing which illustrates the order which the magnetic flux density becomes a positive phase component and the order which becomes a negative phase component for each phase number m. The graph which shows the difference of the effective value of the forward / reverse phase magnetic flux density for each number of slots of each pole and phase when the energization order h = 2. The graph which shows the difference of the effective value of the forward / reverse phase magnetic flux density for each number of slots of each pole and phase when the energization order h = 1. The graph which shows the normalized difference of the effective value of the forward / reverse phase magnetic flux density for each number of slots of each pole and phase when the energization order h = 2. The graph which shows the normalized difference of the effective value of the forward / reverse phase magnetic flux density for every number of slots of each pole and phase when the energization order h = 1. The explanatory view which shows the structure of the electric motor when the number of slots of each pole and each phase is set to a value 2 in a 5-phase winding. The explanatory view which shows the structure of the electric motor when the number of slots of each pole and each phase is set to the value 3 in a 5-phase winding. Explanatory drawing which shows the structure of the electric motor which made the 5-phase winding a short section winding with γ = 3/5. The explanatory view which shows the structure of the electric motor provided with the winding for 13 phases as a 2nd Embodiment. Explanatory drawing which shows the appearance of a star-shaped annular connection of 13-phase windings with a span 5. The schematic diagram which shows the relationship between the line current and the coil current in the case of 2 poles and the case of 6 poles. The graph which shows the current distribution of each phase coil in 2 poles (energization order h = 1) and 6 poles (energization order h = 3). Explanatory drawing which shows an example in which a 13-phase winding is connected in a star shape ring in each span. Explanatory drawing which shows the structure of the outer rotor type electric motor as another embodiment. Explanatory drawing which illustrates the structure of the sequential type SPM motor which is another form of an electric motor. Explanatory drawing which illustrates the structure of the sequential type IPM motor which is another form of an electric motor.

A. Device configuration of the first embodiment:
As shown in FIG. 1, the electric motor operation system 20 of the first embodiment includes an electric motor 30 having an m-phase winding (m = 5) and a drive device 60 that controls energization of the electric motor 30. The drive device 60 includes an m-phase inverter 70, a battery 72 that supplies power to the inverter 70, a voltage sensor 74 that measures the supply voltage Vin from the battery 72, and five current sensors that measure the m-phase current of the inverter 70. It includes 81, 82, 83, 84, 85, and a controller 88 that controls the operation of the inverter 70. The controller 88 includes an angle signal α from the rotation angle sensor 35 provided on the output shaft 32 of the electric motor 30, a signal of the supply voltage Vin from the voltage sensor 74, and a line current It1 flowing through each winding from the current sensors 81 to 85. , It2, It3, It4, It5 signals are input, and on / off of each switching element of the inverter 70 is controlled based on the instruction from the upper ECU 90. By turning off / off each switching element of the inverter 70, a desired current flows in the winding of each phase of the electric motor 30, and the electric motor 30 is operated with the torque Nq and the rotation speed Rt obtained from the ECU 90, and the output shaft. Drives the load LD coupled to 32. The connection between the inverter 70 and each phase winding of the electric motor 30 will be described later.

The electric motor 30 of the first embodiment is an induction machine, and is a sectional view taken along the axial direction of the output shaft 32. FIG. 2, and a 3-3 arrow view taken along a plane perpendicular to the output shaft 32 in FIG. As shown in FIG. 3, the case 36 is housed, and the output shaft 32 thereof is rotatably supported by two bearings 37 and 38 fixed to the case 36. The electric motor 30 includes a rotor 40 fixed to the output shaft 32 and a stator 50 fixed to the case 36. The rotor 40 is a short-circuit ring that short-circuits a disk-shaped rotor core 41, a plurality of secondary conductors 43 provided on the outer circumference of the rotor core 41 at predetermined intervals, and a plurality of secondary conductors 43 on both axial sides of the rotor core 41. It includes 45. On the other hand, the stator 50 includes a stator core 51 that surrounds the rotor core 41 with a slight air gap, a plurality of teeth 53 provided inside the stator core 51, and a coil 55 housed between the teeth 53.

The electric motor 30 of the first embodiment is a m = 5-phase induction machine, and in FIG. 3, the distinction between the 5-phase windings (also referred to as a coil) is indicated by reference numerals A, B, C, D, and E. The winding start and winding end of each winding are indicated by unsigned and minus-signed, such as "A" and "-A". Since the electric motor 30 of the first embodiment includes one set of five-phase windings, the variable p indicating the number of sets of m-phase windings in the electric motor is a value of 1. Therefore, the average θ of the mechanical phase angle difference between the windings, which is the adjacent mechanical phase angle in each phase, is calculated by the following equation (1).
θ = 360 ° / (m · p)… (1))
In the first embodiment, since it is represented by
θ = 72 °
Will be. The winding pitch γ is 3/5 (0.6) as shown in the figure. Further, the number of slots q for each pole and each phase is a value of 2.

FIG. 4 shows how the windings of the electric motor 30 are connected. The windings A, B, C, D, and E are the windings of the phase having a mechanical phase difference angle L · θ apart from the value of the span L (L is a positive integer of m / 2 or less). It is connected in a star-shaped annular connection, and in this embodiment, the span L of the connection is L = 2. This means that the connections of the windings A to E are every other when viewed from each of the five output terminals T1, T2, T3, T4, and T5 of the inverter 70 shown in FIG. To do. An example of connection when the span L is a value of 1 is shown in FIG. In the case of 5 phases, the span L is limited to value 1 or value 2. This is because L = 3 is substantially the same as L = 2. As the number of phases increases, the span L that can be taken increases, and in the case of m = 13 phases, the span L can be taken up to 6. In FIG. 21, which will be described later, L = 1 to 4 are illustrated.

B. Operation by drive device 60:
The controller 88 of the drive device 60 that drives the electric motor 30 has a built-in CPU and executes a motor control routine that involves switching the number of poles shown in FIG. This process is repeatedly executed from the time when the power is turned on to the drive device 60. When the controller 88 starts the process shown in FIG. 6, it inputs a command from the upper ECU 90 (step S100). The ECU 90 obtains the torque Nq and the rotation speed Rt to be output by the electric motor 30 based on the state of the load LD, and instructs whether to switch the electric motor 30 to the number of poles capable of outputting the torque Nq and the rotation speed Rt.

In response to this command, the controller 88 determines whether it is necessary to switch the number of poles (step S110). The relationship between the number of poles of the electric motor 30, the torque Nq, and the rotation speed Rt is shown in FIG. In FIG. 7, the solid line J8 shows the torque-rotation speed relationship when the motor 30 has eight poles, and the solid line J4 shows the torque-rotation speed relationship when the motor 30 has four poles. As shown in the figure, the electric motor 30 of the first embodiment can output a high torque in a low rotation speed range when operating with 8 poles, and has a high rotation speed in a low torque range when operating with 4 poles. can do.

If there is no instruction from the ECU 90 to switch the number of poles, nothing is performed and this routine is temporarily terminated. On the other hand, if the operation with four poles is instructed, the energization order h is a value 1, and the electric motor 30 is operated with four poles, and flows between windings having a mechanical phase angle adjacent to each other in each phase. The electrical phase difference δ of the current is given by the following equation (2).
δ = h ・ θ ・ p = h ・ 360 ° / m… (2)
The energization of the m-phase winding is controlled so as to be (step S120). In this case, since h = 1 and m = 5, δ = 72 °.

Further, if the operation with 8 poles is instructed, the energization order h is a value 2, and the electric motor 30 is operated with 8 poles (step S130). At this time, the electrical phase difference δ of the current flowing between the windings having the mechanical phase angles adjacent to each other in each phase is h = 2 and m = 5, so that the phase difference δ = 144 °.

The state of this control will be described with reference to FIGS. 8 to 10. As shown in FIG. 8, it is assumed that one of the outputs from the inverter 70 is connected to the terminal T1 of the electric motor 30. In the present embodiment, since the five-phase windings of the electric motor 30 are connected in a star shape with a span L = 2, coils A and D are connected to the terminals T1. The relationship between the phase difference δ and the amplitude of the linear current It at this time is shown in FIG. In this case, if the current flowing from the inverter 70 to the terminal T1 is called the line current It1 and the currents flowing through the coils A and D are called the coil currents IA and ID, the line current It1 flows through the coils A and D and the coil current IA. , The composite of ID is equal to the line current It1. Since the mechanical phase angle difference between the windings through which the current flows from the terminal T1 changes depending on the span L with respect to the minimum mechanical phase angle difference θ, the mechanical phase angle difference between the two coils A and D is (ML) · θ = 216 °. As shown in FIG. 9, in the case of 4 poles (h = 1), the electrical phase difference between the coil currents IA and ID is h · (mL) · θ · p = 216 °, and 8 poles. In the case of (h = 2), the electrical phase difference between the coil currents IA and ID is h · (mL) · θ · p = 432 ° = 72 °. Further, the current amplitude | IA | of the coil current flowing through the winding A in this case is given by the following equation (3).
| IA | = | {It1 / sin (h ・ (mL) ・ θ ・ p ・ 2π / 360 ° / 2)} / 2 |… (3)
Is required as. Specifically, when the current amplitude of the coil current IA is obtained,
When the energization order h = 1,
| IA | = | {It1 / sin (144 ° ・ 2π / 360 ° / 2)} / 2 |
= 0.52573 · | It1 |
When the energization order h = 2,
| IA | = | {It1 / sin (432 ° ・ 2π / 360 ° / 2)} / 2 |
= 0.85065 · | It1 |
Will be. Therefore, the current amplitudes of the coil currents IA and ID for the same line current It1, that is, the torque of the motor is smaller when the energization order h = 1. As a result, when the energization order h = 1, that is, when there are four poles, the torque Nq is smaller and the rotation speed Rt is higher (FIG. 7).

The phase difference δ of the current flowing between the windings having the adjacent mechanical phase angles in each phase is 72.
The amplitude of the coil current in the case of ° (h = 1) and the case of 144 ° (h = 2) is shown in FIG. In the figure, the horizontal axis shows the arrangement of windings A to E. In the figure, "○" indicates the beginning of the winding, and "○" indicates the end of the winding. As shown in the figure, in the electric motor operation system 20 of the first embodiment, when the drive device 60 switches the number of poles (4 poles, 8 poles), the energization order h is switched (h = 1, 2), respectively. The electrical phase difference δ of the current flowing between the windings, for example, the coil A and the coil B, which are the mechanical phase angles adjacent to each other in the phase,
δ = h · 360 ° / m
The m-phase winding is energized so as to be.

The force (torque) that rotates the rotor 40 of the electric motor 30 when such energization is performed will be examined. Based on the theoretical formula of the magnetic flux density generated in the air gap between the rotor 40 and the stator 50 of the electric motor 30 when a current of the energization order h is energized from the inverter 70, only the coefficient term that determines the amplitude of the magnetic flux density B is extracted. And the nth-order magnetic flux density amplitude Bn in the magnetic flux density B have the following relationship (4).
Bn∝sin {(1-γ / 2) n ・ π} ・ cos {(1 / (2 ・ m ・ q)) n ・ π} / n… (4)
There is a relationship of. here,
γ: Ratio of winding pitch of phase winding to magnetic pole pitch m: Number of phases of winding q: Number of slots for each pole and phase based on the number of poles when h = 1 (q> 1)
n: Order of magnetomotive force distribution (pole logarithm)
Is. Since the right-hand side of the above equation is fixed in the motor 30 except for n, the right-hand side of the relationship (4) is changed to an expression using the function f in order to simplify the display.
Bn∝f (n)
I will express it as.

The magnetic flux density Bn of the nth-order component acting on the air gap between the rotor 40 and the stator 50 is such that l is an arbitrary integer (including 0).
n + h = l ・ m
When is satisfied, the magnetic flux of the opposite phase component becomes dominant, and the torque of the motor 30 due to the nth order magnetic flux density Bn becomes a negative torque. On the other hand
n−h = l · m
When is satisfied, the magnetic flux of the positive phase component becomes dominant, and the torque of the motor 30 due to the nth-order magnetic flux density Bn becomes positive torque.

The magnetic flux density Bn of the nth-order component acting on the air gap between the rotor 40 and the stator 50 is such that l is an arbitrary integer (including 0).
n + h ≠ l ・ m or n−h ≠ l ・ m
In the case of, since the rotating magnetic field component is not included, the magnetic flux density Bn of the nth-order component can be ignored. For example, if the phase number m = 5 and the energization order h = 1, the magnetic flux density Bn in the case of n = 2, 3 or the like can be ignored.

FIG. 11 shows the case where the energization order h = 1 and h = 2 in the m-phase inducer, where the order in which the magnetic flux density B is a positive phase component is n1 and the order in which the magnetic flux density B is a negative phase component is n2. It is shown separately. Considering the force applied to the rotor 40, that is, the torque when the energization order h = 1 or 2, if the motor 30 is a 5-phase motor, the positive torque is n1 = 1, 6, 11, 16, 21, 26. The negative torque is proportional to the effective value of the magnetic flux density in the case of ..., And the negative torque is proportional to the effective value of the magnetic flux density in the case of n2 = 4, 9, 14, 19, 24, 29 ... Therefore, the difference ΔB between the effective value BP of the positive phase magnetic flux and the effective value BN of the negative phase magnetic flux that generate the positive torque is proportional to the magnitude of the torque at the energization order. Expressed using the orders n1 and n2 shown in FIG. 11, the effective value Bp of the positive phase magnetic flux has the following relationship (5).
BP ∝ √ [Σ {f (n1)} ² ]… (5)
The effective value Bn of the reverse phase magnetic flux can be expressed as the following relationship (6),
BN∝√ [Σ {f (n2)} ² ]… (6)
Can be represented by. Here, “Σ” in the equation (5) indicates an operation of summing the effective values of the magnetic fluxes at n1 with the corresponding number of phases shown in FIG. Specifically, if the number of phases m = 5, that is, the 5-phase electric motor 30, the cumulative value of the effective value of the magnetic flux when n1 = 1, 6, 11, 16, 21, 26, 31 ... Is obtained. It will be. On the other hand, "Σ" in the equation (6) indicates an operation of summing the effective values of the magnetic fluxes at n2 with the corresponding number of phases shown in FIG. Specifically, in the case of the 5-phase electric motor 30, the cumulative value of the effective value of the magnetic flux in the case of n1 = 4, 9, 14, 19, 24, 29, 34 ... Is obtained.

Therefore, the torque Nq applied to the rotor 40 is
Nq∝ΔB = BP-BN
Can be obtained as. Although all the orders n satisfying the above conditions are shown in FIG. 11, in reality, some of the orders n may be obtained. The order n used in the calculation is a positive phase component or a negative phase component. In any of the components, the number of magnetic poles Q generated at each energization order h = 1 or 2 is Q = 2 × p × n, and is based on the total number of slots S = 2 · n · m · p · q of the stator 50. Since a large number of magnetic poles are not generated, n (n1 and n2 in FIG. 11) satisfying n ≦ m · q, which is a condition of Q ≦ S, is the target of calculation. By obtaining the difference ΔB between the effective values BP and BN of the positive and negative phase magnetic fluxes with respect to the order n, the torque at the energization order h = 1 or 2 can be obtained in the electric motor 30.

Actually, in the electric motor 30 of the first embodiment, graphs showing the difference ΔB between the effective values BP and BN of the forward and reverse phase magnetic flux densities at the energization orders h = 2 and h = 1 are shown as FIGS. 12A and 12B. In the figure, the horizontal axis is the number of slots q for each pole and each phase. Further, in the graph, the number of phases of the electric motor 30, 5 phases, 7 phases, 9 phases, 11 phases, 13 phases and 15 phases are used as parameters. It is understood that the difference ΔB between the effective values BP and BN of the forward / reverse phase magnetic flux density is the maximum when the energization order is 2 regardless of the number of phases and the number of slots q = 2 for each phase of each pole. it can. In order to make this point easier to understand, the contents of FIGS. 12A and 12B are normalized based on the case where the number of slots q of each pole and each phase is a value 1, as shown in FIGS. 13A and 13B. is there. According to FIG. 13A, in the 5-phase motor, when the number of slots q of each phase of each pole is between the value 2 and the value 6, the number of slots q of each phase of each pole is the value 1 at the energization order h = 2. It can be seen that the difference ΔB between the effective values BP and BN of the forward and reverse phase magnetic flux densities increases, that is, the torque output by the motor 30 increases.

As described above, according to the electric motor operation system 20 of the first embodiment, a five-phase induction machine is used as the electric motor 30, and the mechanical phase angles between the windings are mechanically adjacent to each of the five phases. The phase angle difference θ is set to θ = 360 ° / 5 = 72 °, the number of slots q for each pole and each phase when the energization order h by the inverter 70 is a value of 1, and the controller 88 passes through the inverter 70. , The electric angle phase difference δ of the current flowing between the windings which is the adjacent mechanical phase angle in each phase is δ = h · 360 ° / 5, that is, the energization order h = 1 when the energization order h = 1 or 2. The 5-phase winding is energized so that the temperature is 72 ° and the energization order h = 2 is 144 °. As a result, as shown in FIGS. 13A and 13B, especially when the energization order h = 2, in the motor 30 with a 5-phase winding, the difference ΔB between the effective values BP and BN of the forward and reverse phase magnetic flux densities is different for each pole. The number of slots q in each phase can be increased by about 10% from the case where the value is 1. Therefore, even if the number of slots q for each pole and each phase is 2 or more and 6 or less, the efficiency does not decrease due to the switching of the energization order. Therefore, by switching the energization order h, as shown in FIG. 7, the operating region from the operating region of high torque and low rotation to the operating region of low torque and high rotation can be expanded. In particular, the maximum torque during 8-pole operation when the energization order h is switched to the value 2 can be made higher than when the number of slots q for each pole and each phase is a value 1. As described above, this effect is not limited to the value 2 of the number of slots q of each phase of each pole, and in the motor 30 with 5-phase winding, the number of slots q of each phase of each pole has a value of 2 to 6. In the range, it can be obtained when the energization order h is a value 2. Further, in the present embodiment, the ratio γ of the winding pitch of the phase winding to the magnetic pole pitch is set to 0.6. Therefore, in the relationship (4), when the pitch ratio γ becomes smaller, the effective value of the magnetic flux density can be increased, and as a result, the difference ΔB between the positive phase magnetic flux density and the negative phase magnetic flux density can be increased.

C. Variations of the first embodiment:
In the first embodiment described above, a five-phase induction machine is used as the electric motor 30, but the number of winding phases is not limited to five, and any odd-numbered phase of five or more can be adopted. Further, the span L can be set to any value of 1 or more. Further, an arbitrary positive integer in which the average θ of the mechanical phase angle difference between the windings, which is the adjacent mechanical phase angle in each phase, has a variable p having a value of 1 or more indicating the number of sets of m-phase windings in the electric motor. As,
θ = 360 ° / (m · p)
It is also possible to set it as a positive integer other than p = 1. For example, in FIG. 14, the rotor 40 of the electric motor 30 is provided with a rotor core 41 and a secondary conductor 43 as in the first embodiment. Further, the stator 50 is provided with a stator core 51, 40 teeth 53, and two sets of 5-phase coils 55. The ratio γ of the winding pitch of the phase winding to the magnetic pole pitch is 3/5 (0.6), and the number of slots q for each pole and each phase is a value of 2.

In this electric motor 30, the average θ of the mechanical phase angle difference between the windings, which is the adjacent mechanical phase angle in each of the five phases, is θ = 360 ° / (5. 2) = 36 °, the number of slots q for each pole and each phase is a value 2 when the energization order h (any integer with h ≧ 1) is a value 1, and the inverter 70 is a machine adjacent to each phase. The electrical phase difference δ of the current flowing between the windings, which is the target phase angle, is δ = 1.360 ° / 5 = 72 ° when the energization order h = 1, and δ = 2 when the energization order h = 2. -Energize the 5-phase winding so that 360 ° / 5 = 144 °. Even in this way, almost the same effect as that of the first embodiment is obtained.

Further, as shown in FIG. 15, the number q of slots for each pole and each phase may be set to a value of 3. In the electric motor 30 shown in FIG. 15, the number of phases m = 5, p = 1, γ = 5/5, and q = 3. Alternatively, as shown in FIG. 16, it is also possible to configure the electric motor 30 with a configuration substantially the same as that of FIG. 15 with γ = 3/5 and a short section winding. The electric motor 30 also has almost the same effect as that of the first embodiment described above.

D. Second embodiment:
Next, the second embodiment will be described. The electric motor operation system 20 of the second embodiment has almost the same configuration as that of the first embodiment, but the electric motor 30 is an induction machine having 13 phases, and the output of the inverter 70 is matched with the number of phases of the electric motor 30. , The difference is that it has the output of 13 phases. The number of terminals of the electric motor 30 is also 13 accordingly, and the inverter 70 and the controller 88 are also prepared for 13 phases, but these are simply scaled up in the number of phases. Therefore, the drawing corresponding to FIG. 1 is omitted.

FIG. 17 shows the configuration of the electric motor 30 provided with windings A to M for 13 phases. Each parameter of the electric motor 30 has the number of phases m = 13, p = 1, γ = 7/13, and q = 2. Further, as shown in FIG. 18, the connection of the windings A to M has a span L = 5. In the electric motor 30, the average θ of the mechanical phase angle difference between the windings, which is the adjacent mechanical phase angle in each of the 13 phases, is θ = 360 ° / (13. 1) = 360 ° / 13, the number of slots q for each pole and each phase is a value 2 when the energization order h (an arbitrary integer with h ≧ 1) is a value 1, and the inverter 70 is adjacent to each phase. The electric angle phase difference δ of the current flowing between the windings, which is the mechanical phase angle, is δ = 360 ° / 13 when the energization order h = 1, and δ = 1080 ° / 13 when the energization order h = 3. The 13-phase winding is energized so as to be.

In the electric motor 30, for example, taking the terminal T1 as an example, as shown in FIG. 19, since the span L has a value of 5, the line current It1 at the terminal T1 flows through the coil A and the coil I. The amplitude of the current flowing through the coil I follows the equation described as the equation (3). As a result, the amplitude of the coil current IA is larger in the case of energization order h = 3, that is, 6 poles than in the case of energization order h = 1, that is, 2 poles. FIG. 20 shows an example of the phase current when the energization order h is a value 1 and when the energization order h is a value 3. Similar to FIG. 10 shown in the first embodiment, in FIG. 20, the horizontal axis shows the arrangement of windings A to M. In the figure, the x mark indicates the beginning of the winding, and the ○ mark indicates the end of the winding. As shown in the figure, in the electric motor operation system 20 of the second embodiment, when the drive device 60 switches the number of poles (2 poles / 6 poles), the energization order h is switched (h = 1, 3). The electric angle phase difference δ of the current flowing between the windings having the mechanical phase angle adjacent to each other in the phase, for example, the coil A and the coil B,
δ = h · 360 ° / m
The m-phase winding is energized so as to be.

It is the same as the first embodiment that the torque can be calculated by obtaining the difference ΔB between the positive phase and the negative phase magnetic flux densities by using the current flowing through each phase coil. According to the electric motor operation system 20 of the second embodiment, a 13-phase induction machine is used as the electric motor 30, and the mechanical phase angle difference θ between the windings, which is the adjacent mechanical phase angle in each of the 13 phases, is determined. When θ = 360 ° / 13 and the energization order h by the inverter 70 is a value 1, the number of slots q of each pole and each phase is set to 2, and the controller 88 passes through the inverter 70 and the mechanical phase angle adjacent to each phase. The electric angle phase difference δ of the current flowing between the windings is δ = h · 360 ° / 13, when the energization order h = 1 or 3, that is, about 41.5 ° when the energization order h = 1, and the energization order h. The 13-phase winding is energized so that the temperature is about 83 ° at = 3. As a result, when the energization order h = 3, in the motor 30 with 13-phase winding, the difference ΔB between the effective values BP and BN of the forward / reverse phase magnetic flux density is larger than the case where the number of slots q of each pole and each phase is 1. , Slightly larger (see Figure 13A). Therefore, by switching the energization order h, as shown in FIG. 7, the operating region from the operating region of high torque and low rotation to the operating region of low torque and high rotation can be expanded.

E. Variations of the second embodiment:
In the second embodiment described above, an induction machine having 13 phases and a span 5 is used as the electric motor 30, but the number of winding phases is not limited to 13 phases, and any odd-numbered phase of 13 or more can be adopted. it can. Further, the span L can be set to any value of 1 or more. FIG. 21 is a schematic view showing a star-shaped annular connection when the span L of the 13-phase winding is set to the values 1, 2, 3, and 4. When the span L = 2 or more, the shape of the coil is omitted for convenience of illustration. In either case, the average θ of the mechanical phase angle difference between the windings, which is the adjacent mechanical phase angle in each phase, is
θ = 360 ° / 13
Is. Of course, it is also possible to provide two or more sets (p ≧ 2) of such m-phase windings. Further, the pitch γ of each coil is not limited to 7/13, and other values may be used for short section winding. Further, the number of slots q for each pole and each phase may be set to a value of 3 to 6. Even if such a configuration is adopted, almost the same effect as that of the second embodiment described above can be obtained.

F. Other embodiments:
(1) The electric motor 30 and the electric motor operation system 20 of the present disclosure can be implemented in various forms other than the above-described embodiment. For example, it can be implemented as an outer rotor type electric motor. A configuration example of such an electric motor 130 is shown in FIG. As shown in the figure, the electric motor 130 has a stator 150 in the center, and a rotor 140 is rotatably arranged on the outer periphery thereof. In the stator 150, 52 teeth 153 are radially provided on the outer circumference of the stator core 151, and coils 55 for 13 phases are wound in the space formed by the teeth 153. On the other hand, the rotor 140 arranged on the outer circumference of the stator 150 includes an outer rotor core 141 and a plurality of secondary conductors 143 arranged at equal intervals on the inner circumference thereof. Each parameter of the electric motor 130 has the number of phases m = 13, p = 1, γ = 7/13, and q = 2. In such an outer rotor type electric motor 130, it goes without saying that the number of phases m of the windings may be other than m = 13, as shown in other embodiments. This also applies to other parameters.

Moreover, the electric motor does not have to be limited to the induction machine. The electric motor may be, for example, a sequential type SPM motor. As illustrated in FIG. 23, this sequential type SPM motor includes a plurality of permanent magnets 247 magnetized in the radial direction on the outer peripheral surface of the rotor core 241. In the case of the sequential type SPM motor in which the rotor core 241 is shown in FIG. 23, the number of poles at the energization order h = 2 is eight poles.

Alternatively, as shown in FIG. 24, it can be implemented as a sequential IPM motor in which a plurality of permanent magnets 347 magnetized in the radial direction are embedded in the rotor core 341. Flux barriers 348 are provided on both sides of the permanent magnets 347 embedded inside the rotor core 341. The flux barrier 348 is composed of air or a non-magnetic material.

Even in such a sequential type motor, as in the induction machine, the number of slots for each phase of each pole is set to q = 2, and the energization order h is switched, so that the operating range of high torque and low rotation is low as shown in FIG. The operating range up to the operating range of high torque rotation can be expanded.

(2) An electric motor operation system consisting of an electric motor and a drive unit for operating the electric motor.
In the motor, the average θ of the mechanical phase angle difference between the windings having the adjacent mechanical phase angles in each phase of the m-phase winding (m is an odd integer of 5 or more) is the m-phase winding in the motor. Let the variable p indicating the number of sets of be an arbitrary positive integer having a value of 1 or more.
θ = 360 ° / (m · p)
Satisfying the above relationship, the connection of the windings of each phase is a phase winding having a mechanical phase angle difference L · θ away from the value of span L (L is a positive integer of m / 2 or less). It is a star-shaped annular connection connecting each other, and when the energization order h (an arbitrary integer of h ≧ 1) is a value 1, the number of slots q of each pole and each phase is 6 ≧ q ≧ 2, and the driving unit Is the electrical phase difference δ of the current flowing between the windings, which is the mechanical phase angle adjacent to each other in each phase.
δ = h · 360 ° / m
In addition, in this motor operation system, the m-phase winding of the motor has a ratio γ of the winding pitch of each phase winding to the magnetic pole pitch. The short winding with 0 <γ <1 may be used, and the drive unit may energize each phase winding by switching the current of the energization order h = 1 or h = 2.

By doing so, by switching the energization order h, the effective value of the positive phase magnetic flux when the energization order h = 2 can be increased in the motor in which the number of slots for each phase of each pole is 6 ≧ q ≧ 2, and the output of the motor can be increased. Can be enhanced. Therefore, it is possible to expand the operating region from the operating region of high torque and low rotation to the operating region of low torque and high rotation without causing a decrease in efficiency due to switching of the energization order.

(3) In such an electric motor operation system, the m-phase winding of the electric motor is a short-section winding in which the winding pitch γ of each phase winding is 1> γ> 0, and the drive unit is the respective drive unit. The phase windings may be energized with currents of the energization order h = 1 and h = 2. By doing so, the effective value of the positive phase magnetic flux when the energization order h = 2 can be increased, and the output of the electric motor can be increased.

(4) In such an electric motor operation system, the winding pitch γ of the electric motor may be set to a value of 0.4 to 0.6. In this way, when the energization order h is switched between h = 1 and h = 2, the effective value of the positive phase magnetic flux when the energization order h = 2 can be set to the maximum value or a value close to this. ..

(5) In such an electric motor operation system, the electric motor may be provided with a 5-phase winding (m = 5). In order to switch the energization order, the number of phases m of the winding needs to be an odd integer of 5 or more, but the smaller the number of phases, the more the number of slots q of each pole and each phase is 1. Since the effective value of the anti-phase magnetic flux is large, if a 5-phase winding having the smallest number of phases m is used, the effect that the number of slots q of each pole and each phase can be easily set to a value of 2 or more can be obtained.

(6) In such an electric motor operation system, the number of slots q = 2 for each pole and each phase when the electric motor has the energization order h = 1. By doing so, the difference between the positive phase magnetic flux density and the negative phase magnetic flux density becomes the largest, and the characteristics of the electric motor can be improved.

(7) In such an electric motor operation system, the electric motor may be an induction machine. In the case of an induction machine, the influence of high-frequency magnetic flux is large, so the effect of reducing the influence of reverse-phase magnetic flux is large. Of course, the electric motor is not limited to the induction machine, and an electric motor operation system using a sequential type SPM motor, a sequential type IPM motor, or the like is also possible.

(8) A mode of an electric motor in which the windings of each phase of the m-phase windings (m is an odd integer of 5 or more) are connected in a star shape may be adopted. In this motor, the average θ of the mechanical phase angle difference between the windings, which is the mechanical phase angle adjacent to each other in each phase, has a variable p indicating the number of sets of m-phase windings in the motor, and the value is 1 or more. As an integer
θ = 360 ° / (m · p)
Satisfying the above relationship, the connection of the windings of each phase is a phase winding having a mechanical phase angle difference L · θ away from the value of span L (L is a positive integer of m / 2 or less). It is a star-shaped annular connection that connects the two, and the electrical phase difference δ of the current between the windings, which is the mechanical phase angle adjacent to each other in each phase, uses the energization order h (any integer with h ≧ 1). hand,
δ = h · 360 ° / m
The number of slots q for each pole and each phase when h = 1 is 6 ≧ q ≧ 2.

This electric motor can increase the difference between the positive phase magnetic flux density and the negative phase magnetic flux density. Therefore, the characteristics of the electric motor can be improved as compared with the electric motor having the number of slots q = 1 for each pole and each phase.

(9) A mode as a driving method of the electric motor is also possible. The driving method of this electric motor is
(A) The average θ of the mechanical phase angle difference between the windings having the adjacent mechanical phase angles in each phase of the m-phase winding (m is an odd integer of 5 or more) is that of the m-phase winding in the electric motor. Θ = 360 ° / (m · p) with the variable p indicating the number of sets as an arbitrary integer with a value of 1 or more.
(B) The connection of the windings of each phase has a mechanical phase angle difference L · θ away from the value of span L (L is a positive integer of m / 2 or less). The number of slots q for each pole and each phase is 6 ≧ q ≧ when (c) the energization order h (any integer of h ≧ 1) is a value 1 and the windings are connected to each other. When the energization order h of the electric motor is switched and the energization order h is switched in accordance with the request for the electric motor, the winding of each phase of the electric motor becomes 2. The electrical phase difference δ of the current flowing between the windings
δ = h · 360 ° / m
The windings of each of the phases are energized so as to be.

By doing so, the difference between the positive-phase magnetic flux density and the negative-phase magnetic flux density of the motor can be increased, so that the characteristics of the motor can be improved as compared with the motor having the number of slots q = 1 for each pole and each phase. By switching the energization order, the electric motor can be driven from the operating region of high torque and low rotation speed to the operating region of low torque and high rotation speed.

(10) In each of the above embodiments, a part of the configuration realized by the hardware may be replaced with software. At least a part of the configuration realized by software can also be realized by a discrete circuit configuration. Further, when a part or all of the functions of the present disclosure are realized by software, the software (computer program) can be provided in a form stored in a computer-readable recording medium. "Computer readable recording medium" is not limited to portable recording media such as flexible disks and CD-ROMs, but is fixed to internal storage devices in computers such as various RAMs and ROMs, and computers such as hard disks. It also includes external storage devices that have been installed. That is, the term "computer-readable recording medium" has a broad meaning including any recording medium in which data packets can be fixed rather than temporarily.

The present disclosure is not limited to the above-described embodiment, and can be realized by various configurations within a range not deviating from the gist thereof. For example, the technical features in the embodiments corresponding to the technical features in each form described in the column of the outline of the invention may be used to solve some or all of the above-mentioned problems, or one of the above-mentioned effects. It is possible to replace or combine as appropriate to achieve a part or all. Further, if the technical feature is not described as essential in the present specification, it can be appropriately deleted.

20 motor operation system, 30 motor, 32 output shaft, 35 rotation angle sensor, 36 case, 37 bearing, 40 rotor, 41 rotor core, 43 secondary conductor, 45 short circuit ring, 50 stator, 51 stator core, 53 teeth, 55 coil, 60 Drive, 70 Inverter, 72 Battery, 74 Voltage Sensor, 81-85 Current Sensor, 88 Controller, 130 Motor, 140 Rotor, 141 Outer Rotor Core, 150 Stator, 151 Stator Core, 153 Teeth, 241 Rotor Core, 247 Permanent Magnet, 341 Rotor core, 347 permanent magnet, 348 flux barrier, AM coil (winding), LD load, T1-T5 terminal

Claims (9)

An electric motor operation system (20) including an electric motor (30) and a drive unit (60) for operating the electric motor.
The electric motor
The average θ of the mechanical phase angle difference between the windings that are adjacent mechanical phase angles in each phase of the m-phase winding (m is an odd integer of 5 or more) determines the number of sets of m-phase windings in the motor. Let the indicated variable p be any positive integer greater than or equal to the value 1.
θ = 360 ° / (m · p)
Satisfy the relationship,
The windings of each phase were connected to each other with a mechanical phase difference angle L · θ apart from the value of the span L (L is a positive integer of m / 2 or less). It is a star-shaped ring connection,
The number of slots q for each pole and phase based on the number of poles when the energization order h (any integer with h ≧ 1) is value 1 is 6 ≧ q ≧ 2.
In the drive unit, the electric angle phase difference δ of the current flowing between the windings, which is the mechanical phase angle adjacent to each other in each phase, is
δ = h · 360 ° / m
Energize the m-phase winding so that
Electric motor operation system. The electric motor operation system according to claim 1.
The m-phase winding of the electric motor is a short-section winding in which the ratio γ of the winding pitch and the magnetic pole pitch of each phase winding is 0 <γ <1.
The drive unit is an electric motor operation system that energizes each phase winding by switching a current of the energization order h = 1 or h = 2. The electric motor operation system according to claim 1.
The m-phase winding of the electric motor is a short-section winding in which the winding pitch γ of each phase winding is 1>γ> 0.
The drive unit is an electric motor operation system that energizes each of the phase windings with currents of the energization orders h = 1 and h = 2. The electric motor operation system according to claim 2 or 3, wherein the winding pitch γ of the electric motor has a value of 0.4 to 0.6. The electric motor operation system according to any one of claims 1 to 4, wherein the electric motor includes a 5-phase winding (m = 5). The electric motor operation system according to any one of claims 1 to 5, wherein the electric motor has a number of slots q = 2 for each pole and each phase based on the number of poles when the energization order h = 1. .. The electric motor operation system according to any one of claims 1 to 6, wherein the electric motor is an induction machine. The average θ of the mechanical phase angle difference between the windings that are adjacent mechanical phase angles in each phase of the m-phase winding (m is an odd integer of 5 or more) determines the number of sets of m-phase windings in the motor. Let the indicated variable p be any positive integer greater than or equal to the value 1.
θ = 360 ° / (m · p)
Satisfy the relationship,
The windings of the respective phases are connected to each other with a mechanical phase difference angle L · θ apart from the value of the span L (L is a positive integer of m / 2 or less). It is an electric motor with a star-shaped ring connection,
The electrical phase difference δ of the current between the windings, which is the mechanical phase angle adjacent to each other in each phase, is the energization order h (an arbitrary integer of h ≧ 1).
δ = h · 360 ° / m
The filling,
An electric motor in which the number of slots q for each pole and each phase based on the number of poles when h = 1 is 6 ≧ q ≧ 2. It ’s a way to drive an electric motor.
(A) The average θ of the mechanical phase angle difference between the windings having the adjacent mechanical phase angles in each phase of the m-phase winding (m is an odd integer of 5 or more) is that of the m-phase winding in the electric motor. The following equation (1), where the variable p indicating the number of sets is an arbitrary integer having a value of 1 or more,
θ = 360 ° / (m · p)
Satisfy the relationship,
(B) The windings of the phases in which the connection of the windings of each phase has a mechanical phase angle difference of L · θ with respect to the value of the span L (L is a positive integer of m / 2 or less) are separated from each other. It is a connected star-shaped annular connection, and (c) the number of slots q for each pole and phase based on the number of poles when the energization order h (any integer of h ≧ 1) is 1 is 6 ≧ q. In the winding of each phase of the motor in which ≧ 2
The energization order h of the electric motor is switched according to the request for the electric motor.
When the energization order h is switched, the electrical phase difference δ of the current flowing between the windings having the mechanical phase angle adjacent to each other in each phase becomes
δ = h · 360 ° / m
The windings of each phase are energized so as to be.
How to drive an electric motor.

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