JP2002006009A - Analyzing method for motor loss and information medium storing its instruction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an analyzing method for motor loss, an analyzing device, and an information medium recording instruction related to the analyzing method, for improved precision in iron loss analysis. SOLUTION: The iron loss of a motor is analyzed from its magnetic field analyzing result. A hysteresis loss and an eddy-current loss are estimated from a magnetic-flux density analyzing result of a motor. The eddy-current loss is directly analyzed by magnetic-field analysis, which is compared with the estimated eddy-current loss. If the former is larger than the latter, a correction coefficient is acquired from the eddy-current loss which is acquired directly and the eddy-current loss which is estimated. The correction coefficient is used to correct the estimated hysteresis loss, and a sum of the directly-acquired eddy-current loss and the corrected hysteresis loss is taken as iron loss. Thus an analyzing device for motor loss is provided for performing the analyzing method for the motor loss, with an information medium housing an instruction to a computer which performs the analyzing method provided as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loss analysis method for a three-phase synchronous motor used as a motor or a generator and an analyzer thereof. More specifically, the present invention relates to a PM motor loss analysis suitable for a motor or a generator of an electric vehicle. The present invention relates to a method, an analysis apparatus, and an information medium on which instructions related to the analysis method are recorded.

[0002]

2. Description of the Related Art Conventionally, a permanent magnet type synchronous motor (PM
Motor) achieves an efficiency of 90% or more, and is therefore suitable for electric vehicles and already in practical use.
It is also used in hybrid electric vehicles that use a motor for auxiliary power. In recent years, in such motor design, magnetic field analysis has been frequently used, and even loss analysis has been performed, and it has become possible to predict performance to some extent without performing experiments with prototypes one by one.

A major part of such motor loss analysis is iron loss analysis. In this iron loss analysis, magnetic flux analysis is used to obtain a magnetic flux density distribution in each part of the motor, and the iron loss in that portion is estimated from the magnetic flux density. Is being done. In this case, the iron core of the motor is a laminated magnetic steel sheet, but the iron loss of the magnetic steel sheet is based on the function of the magnetic flux density, and the relationship between the magnetic flux density and the iron loss is based on the iron loss of the magnetic steel sheet itself. Obtained from measurement data.

[0004]

However, the above-mentioned iron loss data of the electromagnetic steel sheet is measured under the alternating magnetic flux. However, the magnetic flux of each part in the actual motor is a rotating magnetic flux and is close to the alternating magnetic flux. There aren't many places that are operating in state. Therefore, the calculated iron loss only estimates the iron loss value based on the result under the alternating magnetic flux to the last, and the iron loss according to such estimation becomes a value smaller than the actual value. . Therefore, it is often the case that the coefficients are calculated based on the past back data and corrected to match the data such as the motor efficiency of the actual machine, but there is a problem that the analysis accuracy is not yet sufficient. Was.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and provides a motor loss analysis method, an analysis apparatus, and an instruction related to the analysis method, which can improve the accuracy of iron loss analysis. It is to provide a recorded information medium.

[0006]

The present inventors have established an eddy current analysis method for a magnetic steel sheet of a motor so far. The method is a method using a motor magnetic field analysis model, which is an analysis model of a laminated electromagnetic steel sheet and provided with an electrical insulating layer for faithfully modeling an actual lamination state. According to this, the eddy current loss distribution in the motor can be known. On the other hand, it is also possible to obtain the iron loss distribution from the magnetic flux density distribution conventionally performed. The iron loss includes an eddy current loss and a hysteresis loss (the sum of them). Therefore, the present inventors have intensively studied whether or not the iron loss analysis accuracy can be improved by comparing the eddy current loss of the two, and as a result, the accuracy can be improved in the iron loss analysis which was not in the range of estimation so far. It has been found that the present invention has been completed.

That is, the motor loss analysis method of the present invention is as follows.
A method for analyzing motor loss, characterized in that the motor loss is analyzed from the results of analysis of the stator part iron loss, the rotor part iron loss, and the eddy current analysis of the magnet part.

A preferred embodiment of the motor loss analysis method according to the present invention is a method for analyzing iron loss of a motor from a magnetic field analysis result of a motor. If the former is larger than the latter, the eddy current loss is directly analyzed by magnetic field analysis, and the eddy current loss directly obtained is compared with the eddy current loss estimated from the magnetic flux density. The correction coefficient is calculated from the eddy current loss directly calculated from the eddy current loss and the eddy current loss estimated from the magnetic flux density.Then, the correction coefficient is used to correct the hysteresis loss estimated from the magnetic flux density. The sum of the loss and the corrected hysteresis loss is defined as iron loss.

Further, another preferred embodiment of the method for analyzing motor loss according to the present invention is a method for analyzing iron loss of a motor from a magnetic field analysis result of a motor. Estimate the hysteresis loss and eddy current loss from the analysis results, directly analyze the eddy current loss by magnetic field analysis, compare the directly obtained eddy current loss with the eddy current loss estimated from the magnetic flux density, If it is smaller, a correction coefficient is calculated from the eddy current loss directly obtained and the eddy current loss estimated from the magnetic flux density, and then both the eddy current loss and the hysteresis loss estimated from the magnetic flux density are corrected using the correction coefficient. Then, the sum of the corrected eddy current loss and the hysteresis loss is defined as an iron loss.

[0010] Still another preferred embodiment of the analysis method of the present invention is characterized in that the iron loss analysis part is a stator constituting a motor.

In another preferred embodiment of the analysis method of the present invention, the eddy current loss per unit volume at each portion of the stator is defined by the eddy current loss per unit volume at the center of the teeth of the stator. The ratio of the eddy current loss standard value of each part of the stator directly obtained from the eddy current analysis to the eddy current loss standard value of each part of the stator estimated from the magnetic flux density is calculated as a correction coefficient for each part of the stator. It is characterized by doing.

Still another preferred embodiment of the analysis method according to the present invention is a method for analyzing iron loss of a motor from a result of a magnetic field analysis on the motor, wherein an analysis part is a rotor part constituting the motor, By directly analyzing the eddy current loss of the rotor part by magnetic field analysis, the hysteresis loss of the rotor part is estimated from the ratio of the hysteresis loss of the stator part and the eddy current loss of the stator part. The sum of the calculated rotor part hysteresis loss and the rotor part iron loss is used as the core loss.

Further, another preferred embodiment of the analysis method of the present invention is characterized in that the motor loss is analyzed by further adding the analysis result of the eddy current of the magnet part of the motor. Further, another preferred embodiment is characterized in that the eddy current analysis of the magnet is analyzed by a 1/2 model of the actual length of the magnet, and when the rotor core is a bulk material, the analysis is performed by a 1/2 model of the actual length of the rotor. The eddy current loss of the rotor is analyzed. Further, a direct analysis of the eddy current loss is performed using a half-thickness model of the magnetic steel sheet, and an eddy current analysis is directly performed using the electrical conductivity of the material.

According to still another preferred embodiment of the analysis method of the present invention, in a coefficient map used for estimating a hysteresis loss and an eddy current loss from a magnetic flux density based on a magnetic field analysis result, a motor having a hysteresis loss flows. The dependence on the current fundamental frequency is a coefficient map that is based on the first power of the frequency. Note that the coefficient map is characterized in that the iron loss is constant at a saturation magnetic flux density of the material or higher.

[0015] The motor loss analysis device of the present invention comprises:
The method is characterized by executing the motor loss analysis method as described above. Further, the information medium of the present invention is characterized by storing instructions for a computer that executes the above-described analysis method.

[0016]

According to the motor loss analysis method and analysis apparatus of the present invention, it is possible to perform an analysis in which the effects of harmonics on the rotating magnetic flux and the magnetic flux density in the motor are properly incorporated. As a result,
It is possible to improve the accuracy of iron loss analysis, which is not in the range of estimation. At the same time, the basis of the iron loss analysis can be made clearer, so that the number of trial productions for confirmation can be reduced, and the work efficiency can be improved in terms of time and cost.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail, but first, a technical background will be added a little before explaining the technical contents of the invention. The magnetic field analysis software used by the present inventors is J-MAG of the Japan Research Institute, Limited. If this is used, eddy current analysis can be performed (however, three-dimensional analysis is required for more accurate eddy current analysis), but unfortunately, hysteresis loss cannot be analyzed. In addition, if eddy current analysis can be performed, it is possible to predict the heat generation of the magnet in advance, which is more convenient.

[0018] Against this background, the present inventors have worked on actual analysis of a motor in three dimensions and established an eddy current analysis method.
Specifically, it is an analysis model of laminated electromagnetic steel sheets used as a stator or a rotor, wherein an electric insulating layer for faithfully modeling an actual laminated state is provided. It was established by a magnetic field analysis model of a motor. On the other hand, we also worked hard on estimating iron loss distribution from magnetic flux density distribution to conduct iron loss analysis.
As a result, the technical content of the present invention has been reached.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the contents of the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view showing an example of the brushless motor. Hereinafter, the technical contents of the present invention will be described using the surface magnet motor (SPM) as an example. The motor to be analyzed has the following configuration. That is,
The stator has 12 poles, a split core and concentrated winding. FIG. 2 is a diagram showing one frame of the split core. A 0.35 mm electromagnetic steel sheet is used. The product name is 35H360. A magnet wire having a diameter of 1.2 mm is used and has 54 turns. The stator is manufactured using the split core technology, with an inner diameter of 52 mm and an outer diameter of 108 mm.

One pole is formed by stacking 342 pieces shown in FIG. After winding, the stator was assembled by laser welding. The stack thickness is 119.7 mm. The length of the parallel portion of the teeth of the stator is 19.5 mm, the dimension of the opening is 1.1 mm, the width of the teeth of the stator is 8.2 mm,
The depth of the opening is 1.0 mm and the angle of the tooth shoulder is 44.5 degrees (see FIG. 2). The air gap is 0.65 mm.

The rotor is formed by arranging parallel-magnetized magnets in the shape of a cylinder on the rotor surface. Specifically, radius 2
The inner radius is 22 mm, the outer radius is 14 mm and the maximum thickness is 3.35 m on a 2 mm rotor iron (carbon steel: S40C).
m, (height is about 4.96 mm), and width is 16.5 mm.
The magnet used was an Nd magnet. Product name is Neo
max35EH. Three magnets were arranged in the axial direction, and the length was set to 119.7 mm. In addition,
The shaft diameter (rotor) of the motor is 20 mm.

FIG. 3 is a connection diagram. A is U phase, B is V
The phase C is the W phase and the Y connection. The four poles are in parallel.

The surface magnet type (SP
M) is the configuration of the motor. On the other hand, the motor having the above specifications is a prototype, and a performance test has been performed to evaluate the output efficiency and the like. Using the evaluation results, the results of the magnetic field analysis and the iron loss analysis according to the present invention were verified. In the two-dimensional magnetic field analysis, the current versus torque characteristics agreed with the experimental results. At this time, the number of elements was 1928 (the number of nodes was 2041). Hereinafter, it is described as 1928E (2041N). It has also been found that a sufficient analysis can be performed by analyzing the electric angle in steps of 10 degrees. The model is shown in FIG. What is shown is 1 /
There are four models. This also shows a quarter cross section of the actual motor itself.

The three-dimensional magnetic field analysis is obtained by stacking two-dimensional surfaces in the axial direction. An air layer is provided on one surface to insulate eddy currents. In addition, symmetric boundary conditions are set on other surfaces. By doing so, the actual thickness of one electromagnetic steel sheet
Eddy current analysis becomes possible with a dimension of / 2. Even in the three-dimensional analysis, the torque can of course be correctly analyzed, and a torque value having a magnitude corresponding to the thickness can be obtained.

In the eddy current analysis of the magnetic steel sheet, five layers including the air layer were formed, and the thickness was 0.18 mm. At this time, the thickness of the air layer was 0.005 mm. The ratio of the thickness of each element layer is 1: 1: 4: 10: 20 from the surface side of the electromagnetic steel sheet.
And In addition, the magnet eddy current analysis has six layers, and the thickness is two.
0.2 mm, of which the air layer thickness is 0.25 mm
Met. The ratio of the thickness of each element layer is 5:
5: 10: 20: 50: 314. The rotor eddy current analysis was also performed in six layers, the thickness was 60.85 mm, and the air layer thickness was 1.0 mm. The ratio of the thickness of each element layer is 20: 20: 40: 80: 200: 8 from the air layer surface side.
57.

The Nd magnet characteristics are the same as those of Neomax 35EH.
Using the value at 00 ° C., the current is sinusoidal. 35H36
0 Electrical conductivity of electrical steel sheet is 2.222 * 10⁶[1 / o
hmm], 5.848 * 10 for S40C⁶[1 / ohm
m], Nd magnet is 6.944 * 10 ⁵[1 / ohmm]
Therefore, these values are used in eddy current analysis.
Was.

<Analysis of Eddy Current Loss of Stator> Although the numbered portions in FIG. 4 correspond to the analysis portion, the stator was divided into ten portions, and the eddy current loss in each portion was analyzed.
The stator is divided into three phases of u, v, and w phases, and portions corresponding to the same position are given the same numbers. Although not shown in the drawing, from the result of the magnetic field analysis, the flow of the magnetic flux in the motor is a rotating magnetic flux in most parts, and only near the center of the stator teeth (parts 17 and 18 in FIG. 4). Is close to the alternating magnetic flux. Therefore, the present inventors have conceived of comparing eddy current losses using a division model as shown in FIG.

It is expected that eddy current loss is increased due to the rotating magnetic flux at the tip ends 2 and 14 of the tooth portions. Also, considering the rotating direction of the rotor, the portions 14, 16, 18, 20 and 22 where the magnetic flux density is high are higher. Are the equivalent positions 2, 15, 17, 1
It is expected that the loss will be greater than at sites 9 and 21. Here, 50 rotations / sec. Was analyzed (the frequency of the current is equivalent to 200 Hz). It is expected that eddy current loss near the eddy current loss estimated from the magnetic flux density is obtained at the portions 17 and 18 in the middle of the stator teeth. The estimated eddy current loss from the magnetic flux density is due to eddy current loss (iron loss) based on the measurement results under alternating magnetic flux.

<Creation of Coefficient Map> The relationship between the maximum value Bp of the magnetic flux density and the iron loss W is read from the magnetic steel sheet data. The data was read from the data collection "Non-directional electromagnetic steel strip, Nippon Steel". In addition, since there was no data at a place where the magnetic flux density was high, it was determined by extrapolation. Hysteresis loss Wh
In order to separate the current into the eddy current loss We and the eddy current loss We applied a method assuming that the hysteresis loss Wh is proportional to the first power of the fundamental frequency of the current flowing through the motor. This content is also included in the present invention.

FIG. 5 shows that the maximum value Bp of the magnetic flux density is 0.7T.
(Tesla) shows the result of separating iron loss W into hysteresis loss Wh and eddy current loss We. Iron loss W to frequency f
Is the vertical axis, and the horizontal axis is the frequency f,
The hysteresis loss Wh is the intercept of the vertical axis in the figure, and Wh / f
Is the idea of constant. Therefore, Wh /
The values above f (the difference between W / f and Wh / f at each frequency) all correspond to the eddy current loss We. This separation clarifies the definition of the hysteresis loss Wh.
That is, the area surrounded by the DC BH curve is the hysteresis loss, which does not change even when the current frequency f increases, and is merely multiplied by the current frequency f.

FIG. 6 shows the dependence of the hysteresis loss Wh and the eddy current loss We on the magnetic flux density (the maximum value) Bp obtained by this separation method, with the result at f = 200 Hz as an example. When the saturation magnetic flux density is equal to or higher than the saturation magnetic flux density, the hysteresis loss Wh,
The eddy current loss We was constant. This is also a part of the content of the present invention. This is because there is no reason to physically increase the iron loss at or above the saturation magnetic flux density. Precedents (research papers and the like) of this concept are not limited to the inventor's knowledge.

According to the above method, (the maximum value of the magnetic flux density of the hysteresis loss Wh and the eddy current loss We for each frequency)
Find the Bp dependency and (the maximum value of) the magnetic flux density of each block
A coefficient map used for obtaining the hysteresis loss Wh and the eddy current loss We from Bp was created.

<Analysis Results> Table 1 shows the analysis results. Table 1
, “Block No.” corresponds to the number of each part of the stator in FIG. “3d-ed” in Table 1 is the eddy current analysis result of each block directly obtained from the magnetic field analysis. “MapBp” is the eddy current loss obtained by using the coefficient map and the magnetic flux density of each block obtained from the magnetic field analysis. “Ratio” is the ratio of the two.

In FIG. 4, 1 is considered to be close to the alternating magnetic flux.
It can be seen that 3d-ed is increased by about 10% in the portions 7 and 18. It is considered that the reason is that the magnetic flux is slightly rotating magnetic flux and the magnetic flux density has a harmonic component. In addition, the above 1 which is a rotating magnetic flux
In other sites than 7 and 18, 3d-ed mapBp
Is larger than the cases of the above 17 and 18. In particular, it is large at portions 14 and 22. Although the ratio is smaller than 1 at the portion 2, here the magnetic flux density B
It is considered that this is because p is low and the rotating magnetic flux also moves smoothly. Table 1 also shows the area and volume of each block in FIG.

[0035]

[Table 1]

Table 2 shows the eddy current loss per unit volume of each block. Then, a 3d-ed value per unit volume,
The mapBp value was normalized based on the value of the block 17. Here, the normalization means finding the ratio of the values of the other blocks with reference to the value of the block 17. The normalized values are “3d / 17b” and “map / 17b” in Table 2.
It is. The latter is a value reflecting the magnitude of the magnetic flux density in each block.

Next, this (3d / 17b) value is converted to (map
/ 17b) By dividing by the value, the correction coefficient “h
osei-f ”is required. Therefore, hosei-f, which is the ratio between the two, reflects the degree of the rotating magnetic flux in each block. The “degree of the rotating magnetic flux” includes how much the rotating magnetic flux is with respect to the alternating magnetic flux and how complicated the way of moving the rotating magnetic flux is. In other words, how much higher harmonic components are included in the magnetic flux. To add a further explanation, mapBp uses the maximum value of the magnetic flux density in one cycle in each element in the magnetic field analysis to determine the iron loss in that element. not going. Therefore, the above can be said.

[0038]

[Table 2]

Table 3 shows iron loss values "map-he" obtained by the coefficient map method. Eddy current loss mapB
Subtracting p results in a hysteresis loss map-h. The value corrected by multiplying the hysteresis loss map-h by the correction coefficient hosei-f is “rh-loss”. Hysteresis loss r. Corrected by eddy current loss 3d-ed directly obtained by magnetic field analysis. h-loss is the sum of iron loss r. he-l
oss. As described above, the iron loss of each part of the stator can be analyzed. The eddy current loss of the stator is 7.417m
W, hysteresis loss is 14.219 mW, iron loss is 2
1.636 mW. The hysteresis loss is 1.917 times the eddy current loss. Note that this ratio is used when obtaining a rotor iron loss described later.

[0040]

[Table 3]

By the way, in the above processing, the correction coefficient is obtained by dividing the stator into each part, and the correction is performed. However, Tables 1 to 3 also show how much the correction becomes when the whole stator is corrected as one block. That is, the total column is that. According to this, the corrected hysteresis loss is 14.212 mW, which is almost the same value. Therefore, the correction coefficient may be obtained from the central portion of the stator tooth portion and the whole, and this content is also included in the present invention.

<Magnet Eddy Current Loss, Rotor Iron Loss> From such a background, an eddy current analysis method has been established by working on an actual analysis of a motor in three dimensions. The eddy current analysis of the magnet is used to analyze the above-described model, specifically, the operating characteristics of an actual motor by a magnetic field analysis, and is an analysis model of laminated electromagnetic steel sheets used as a stator or a rotor. The magnetic field analysis model of the motor was provided with an electric insulating layer for faithfully modeling the actual laminated state.

The eddy current loss per 0.175 t of the thickness is 2.
It was 643 mW (for 1/4 motor). Since only the eddy current loss is sufficient for the magnet loss, only the eddy current loss is used here. Eddy current analysis of the rotor was performed in the same manner, and the eddy current loss per 0.175 t of the thickness was 1.192 mW. Assuming that the ratio of the eddy current loss to the hysteresis loss of the rotor is the same as the ratio of the eddy current loss to the hysteresis loss of the stator, the ratio is 1.192 mW * 1.917 = 2.285 mW. Therefore, the iron loss of the rotor is 3.477 mW in total of 1.192 mW of eddy current loss and 2.285 mW of hysteresis loss.

Here, since the magnetic flux in the rotor does not alternate but only fluctuates, it is presently impossible to estimate the iron loss. Since the eddy current loss of the rotor can be obtained from the magnetic field analysis, the estimation of the hysteresis loss was conceived based on the loss. The state of occurrence of iron loss in the stator is as described above. Since it is considered that the same situation occurs in the rotor, the estimation method here is considered to be appropriate.

<Efficiency Analysis> Tables 4 and 5 show the analysis results of the motor output efficiency. Motor 1/4 minute, 0.175t
Table 4 shows that of the motor. The stator iron loss, magnet eddy current loss, and rotor iron loss are the values described above. Output and copper loss are the results obtained from conventional magnetic field analysis. Table 5 is converted to an actual motor. However, the mechanical loss 60W is an estimated value. Since the motor efficiency data in the actual machine is 94% to 95%, it almost matches the result of the output ratio [%] in Table 5, indicating the validity of the analysis.

[0046]

[Table 4]

[0047]

[Table 5]

<Flowchart of Iron Loss Analysis> In order to further clarify the iron loss analysis method of the present invention, a flowchart of the analysis is shown in FIG. In the conventional method, the magnetic flux density distribution is obtained by performing a magnetic field analysis, and the iron loss distribution is obtained by using the iron loss data of the electromagnetic steel sheet. The iron loss data of the magnetic steel sheet was measured under alternating magnetic flux. On the other hand, the magnetic flux in the actual motor is a rotating magnetic flux. In the present invention, the eddy current analysis is performed, the eddy current loss is directly analyzed, the eddy current loss is compared with the eddy current loss obtained by the conventional method, the correction coefficient is determined based on proper consideration, and the original iron The loss value is determined. As is clear from the process of this analysis method, the accuracy of the analysis is naturally improved.

In the above embodiment, the eddy current loss directly obtained from the magnetic field analysis is larger than the eddy current loss obtained from the map. However, the reverse case is also possible. Generally, the case of the embodiment is applied to a motor having a large output. The opposite case is when the magnetic flux density is low. There seems to be an abnormal eddy current loss in the iron loss of the magnetic steel sheet, which is larger than the classical eddy current loss. Eddy current loss obtained directly from magnetic field analysis is classical eddy current loss. Therefore, it may be reversed. In this case, the eddy current loss obtained by the map method may be further corrected to be the eddy current loss. The concept of consideration of the rotating magnetic flux and the harmonic component may be exactly the same (that is, the method of obtaining the correction coefficient is the same). In the flow chart, in which case the We ^m is We ^* become (the general case, such as examples, ^{We 3d} is intact We ^*.).

The motor loss analysis can be performed by executing the above analysis method. The motor loss analysis apparatus of the present invention may be any apparatus that can execute the above-described processing. What is necessary is just to have a magnetic field analysis model as described above, a magnetic field analysis program and an arithmetic processing unit. Further, if an information medium storing instructions to a computer for executing the motor loss analysis method of the present invention is prepared and a computer is used using the information medium, the analysis method of the present invention can be executed. Therefore, such an information medium itself is also included in the scope of the present invention.

Although the present invention has been described in detail with reference to preferred embodiments, the present invention is not limited to the above-described embodiments, and the technical contents described in the claims fall within the scope of the disclosure of the present specification. Included. Also, those skilled in the art can make various modifications within the scope of the above disclosure.

[0052]

As described above, according to the present invention, the eddy current loss obtained directly from the magnetic field analysis and the eddy current loss obtained from the magnetic flux density distribution are compared and appropriately corrected. In addition, it is possible to provide a motor loss analysis method and an analysis device capable of improving the accuracy of iron loss analysis, and an information medium in which instructions related to the analysis method are recorded. In the motor loss analysis system and apparatus of the present invention, it is possible to perform iron loss analysis that properly incorporates the influence of harmonics on the rotating magnetic flux and the magnetic flux density in the motor.
The accuracy of motor loss analysis can be significantly improved. for that reason,
This provides a time and economical advantage that the number of prototypes of the designed motor can be significantly reduced. Further, since the contents of the iron loss analysis are extremely clear physically, the effect alone is extremely large.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a brushless motor.

FIG. 2 is a sectional view showing a top of a split core.

FIG. 3 is a connection diagram of windings.

FIG. 4 is an explanatory diagram of an analysis model.

FIG. 5 is an explanatory diagram relating to iron loss data and separation.

FIG. 6 is a graph showing the dependence of hysteresis loss and eddy current loss on magnetic flux density.

FIG. 7 is a flowchart showing an analysis procedure.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G016 BA01 BA03 BB00 BB04 BC00 BD00 5H621 BB07 BB10 GA01 GA04 GB10 HH01 5H622 CA02 CA07 CA10 CA14 CB03 DD02

Claims (15)

[Claims] 1. A motor loss analysis method, comprising: analyzing a motor loss based on a result of analysis of an iron loss of a stator portion, an iron loss of a rotor portion, and an eddy current of a magnet portion. 2. A method for analyzing iron loss of a motor from a magnetic field analysis result of a motor, comprising: estimating a hysteresis loss and an eddy current loss from a magnetic flux density analysis result based on the magnetic field analysis result of the motor; By directly analyzing the eddy current loss and comparing the directly obtained eddy current loss with the eddy current loss estimated from the magnetic flux density, if the former is larger than the latter, A correction coefficient is obtained from the estimated eddy current loss.After that, the hysteresis loss estimated from the magnetic flux density is corrected using the correction coefficient, and the sum of the directly obtained eddy current loss and the corrected hysteresis loss is determined as the iron loss. 2. The method for analyzing motor loss according to claim 1, wherein: 3. A method for analyzing iron loss of a motor from a magnetic field analysis result of a motor, wherein a hysteresis loss and an eddy current loss are estimated from a magnetic flux density analysis result based on the magnetic field analysis result of the motor. By directly analyzing the eddy current loss and comparing the directly obtained eddy current loss with the eddy current loss estimated from the magnetic flux density, if the former is smaller than the latter, A correction coefficient is obtained from the estimated eddy current loss, and thereafter, the correction coefficient is used to correct both the eddy current loss and the hysteresis loss estimated from the magnetic flux density. The method for analyzing motor loss according to claim 1, wherein the analysis is a loss. 4. The motor loss analysis method according to claim 1, wherein the iron loss analysis part is a stator constituting a motor. 5. An eddy current loss per unit volume at each portion of the stator is normalized by an eddy current loss per unit volume at the center of a tooth portion of the stator, so that each stator is estimated from magnetic flux density. The ratio of the eddy current loss standard value of each part of the stator directly obtained from the eddy current analysis to the eddy current loss standard value of the part is used as a correction coefficient for each part of the stator. The method for analyzing a motor loss according to any one of the above items. 6. A method for analyzing iron loss of a motor from a magnetic field analysis result related to the motor, wherein an analysis part is a rotor part constituting the motor, and an eddy current loss of the rotor part is directly analyzed by a magnetic field analysis. The rotor section hysteresis loss is estimated from the ratio of the stator section hysteresis loss and the stator section eddy current loss, and the sum of the directly obtained rotor section eddy current loss and the estimated rotor section hysteresis loss is calculated as the iron of the rotor section. The motor loss analysis method according to any one of claims 1 to 5, wherein the motor loss is determined. 7. The motor loss is analyzed by further adding a result of analysis of a magnet eddy current of a motor.
7. The method for analyzing motor loss according to any one of Items 6 to 6. 8. The eddy current analysis of the magnet is performed by using a half of the actual length of the magnet.
The motor loss analysis method according to any one of claims 1 to 7, wherein the analysis is performed using a model. 9. The method according to claim 1, wherein when the rotor core is a bulk material, the rotor eddy current loss is analyzed using a half model of the actual length of the rotor. Motor loss analysis method. 10. The direct analysis of the eddy current loss is performed on the magnetic steel sheet.
The method for analyzing motor loss according to any one of claims 1 to 9, wherein the method is performed using a / 2 thickness model. 11. The motor loss analysis method according to claim 1, wherein the eddy current analysis is performed by directly using the electric conductivity of the material. 12. In a coefficient map used for estimating hysteresis loss and eddy current loss from magnetic flux density based on a magnetic field analysis result, the dependence of the hysteresis loss on the fundamental frequency of the current flowing through the motor is equal to the first power of the frequency. 12. The motor loss analysis method according to claim 1, wherein the coefficient map is dependent. 13. The motor loss analysis method according to claim 12, wherein in the coefficient map, iron loss is constant at a saturation magnetic flux density of the material or higher. 14. A motor loss analysis apparatus for executing the motor loss analysis method according to claim 1. Description: 15. An information medium storing instructions for a computer that executes the analysis method according to claim 1. Description: