外文翻譯---電動(dòng)汽車(chē)外轉(zhuǎn)子定子pm無(wú)刷電機(jī)驅(qū)動(dòng)器的比較

1、<p>　　Comparison of Outer-Rotor Stator-Permanent-Magnet Brushless Motor Drives for Electric Vehicles</p><p>　　K.T. Chau1, Senior member IEEE, Chunhua Liu1, and J.Z. Jiang2 1 Department of Electrical and

2、 Electronic Engineering, The University of Hong Kong, Hong Kong, China </p><p>　　2 Department of Automation, Shanghai University, Shanghai, 200072, China</p><p>　　Abstract—In this paper, two eme

3、rging outer-rotor stator-permanent-magnet (PM) brushless motor drives, namely the doubly-salient PM motor drive and the PM hybrid brushless motor drive, are firstly quantitatively compared, which are particularly attract

4、ive for serving as in-wheel motor drives for electric vehicles. In order to enable a fair comparison, these two motor drives are designed with the same peripheral dimensions and based on the same outer-rotor 36/24-pole t

5、opology. By utilizing the cir</p><p>　　Index Terms— Electric vehicle, Finite element method, Machinedesign, Permanent-magnet motor drive. </p><p>　　I. INTRODUCTION</p><p>　　In rece

6、nt years, permanent-magnet (PM) brushless motordrives have been widely used in electric vehicles (EVs) [1-2].The doubly-salient PM (DSPM) motor drive and PM hybridbrushless (PMHB) motor drive are two emerging stator-PMbr

7、ushless motor drives which offer high mechanical integrityand high power density, hence suitable for EV applications [3].Their outer-rotor motor structures are particularly attractive fordirect driving of EVs, especially

8、 for serving as in-wheel motordrives for EVs [4]. How</p><p>　　The purpose of this paper is to newly compare two emergingouter-rotor stator-PM brushless motor drives, namely the DSPMand PMHB types. Based on

9、the same peripheral dimensions,both motor drives are designed with the identical outer-rotor36/24-pole topology. By using the circuit-field-torquetime-stepping finite element method (CFT-TS-FEM) [5], thesteady-state and

10、transient performances of both motor drives arecompared and analyzed. Moreover, the corresponding costeffectiveness will be revealed and</p><p>　　Section II will introduce the motor drive systems and their c

11、onfigurations. In Section III, the design and cost effectiveness of two motor drives will be compared. Section IV will discuss the analysis approach of these two motor drives. The comparison of their performances will be

12、 given in Section V. Finally, a conclusion will be drawn in Section VI.</p><p>　　SYSTEM CONFIGURATION AND OPERATION MODES Fig. 1 shows the schemes of these two outer-rotor stator-PM motor drives when they se

13、rve as the in-wheel motor drives for EVs, especially for motorcycles. It can be seen that these in-wheel motor drives effectively utilize the outer-rotor nature and directly couple with the tire rims. So, these topologie

14、s can fully utilize the space and materials of the motor drives, hence greatly reducing the size and weight for EV applications.</p><p>　　Fig. 1. Topologies of proposed in-wheel motor drives. (a) DSPM. (b) P

15、MHB</p><p>　　The two motor drives configurations are shown in Figs. 2 and 3. It can be found that they have the similar three-phase full bridge driver for the armature windings; while the difference is the H

16、-bridge driver for the DC field windings of the PMHB motor drive. Hence, their operation principles are very similar, except that the controllable field current of the PMHB motor drive. For both motor drives, when the ai

17、r-gap flux linkage increases with the rotor angle, a positive current is applied to th</p><p>　　When these two motor drives act as in-wheel motor drives and are installed in the EVs, they operate at three mo

18、des within the speed range of 0~1000rpm, namely the starting, the cruising, and the charging.</p><p>　　?When the EV operates at the starting mode, it needs a high torque for launching or accelerating within

19、a short time. For the DSPM motor drive, since its PM volume is much more than that of PMHB motor one, it can provide a sufficiently high torque for the EV starting. For the PMHB motor drive, the positive DC field current

20、 will be added to produce the magnetic field together with the PM excited field, hence it also able to offer the high torque for the EV to overcome the starting resistance and </p><p>　　?When the EV runs dow

21、nhill or works in braking condition, it works in the charging mode. In this mode, these two machines can play the role of electromechanical energy conversion, which recover or regenerate the braking energy to recharge th

22、e battery module. Furthermore, for the PMHB machine drive, it can fully utilize its flux controllable ability to maintain the constant output voltage for directly charging the battery, which is more flexible than the DSP

23、M machine drive. </p><p>　　?When the EV runs in the cruising mode or in the steady speed, these stator-PM motor drives will enter the constant-power region. This speed range usually covers 400rpm~1000rpm for

24、 the DSPM in-wheel motor drive. But for the PMHB motor drive, it not only can effectively extend its operating speed range up to 4000rpm which is enough to cover the conventional speed range requirement, but also can reg

25、ulate its magnetic field situation which can make the power module working at the optimal operation </p><p>　　Fig. 2. Configuration of DSPM motor drives.</p><p>　　Fig. 3. Configuration of PMHB m

26、otor drive.</p><p>　　III. COMPARISON OF MOTOR DRIVES STRUCTURES AND FEATURES</p><p>　　The two stator-PM motor drives structures are shown in Figs. 2 and 3. It can be seen that they have the sam

27、e peripheral dimensions and the identical outer rotor, as well as the same 36/24 pole and armature windings. The major difference is their stators and field excitations. The DSPM motor drive is simply excited by PMs, whi

28、ch is located in the stator. But for the PMHB motor drive, it has double-layer stator and double excitations. Its outer-layer stator accommodates the armature windings, wher</p><p>　　? The outer-rotor nat

29、ure can make the machine directly connect with the tire rim, which totally eliminates the mechanical gear transmission and processes high mechanical integrity. Hence, it reduces the power loss, the system complication, a

30、nd the total cost. </p><p>　　? These motor drives fully utilize the whole space, which makes them compact and effective. They arrange the stator to locate the windings and excitations, hence resulting in

31、the robust outer rotor.</p><p>　　? The concentrated armature windings with 36/24 fractional-slot structure can shorten the magnetic flux path and the span of end-windings, which lead to reduce both iron a

32、nd copper materials. Moreover, this arrangement of windings can significantly reduce the cogging torque which usually occurs at conventional PM motor drives. Their different constructions also make them have distinct fea

33、tures. </p><p>　　? For the DSPM motor drive, it has simpler structure than the PMHB one. Also its control strategy is simpler. But this simple structure limits its flexibility due to its uncontrollable ai

34、rgap flux. </p><p>　　? For the PMHB motor drive, since it fully takes advantage of double excitations (both PMs and DC field windings), it can offer flexible airgap flux control, including flux strengthe

35、ning or weakening. In addition, the air-bridge is present to shunt with each PM, hence amplifying the flux </p><p>　　weakening ability. The corresponding field excitation inevitably causes additional power l

36、oss. Nevertheless, this reduction of efficiency can be partially compensated by the efficiency improvement due to airgap flux control. By properly tuning the airgap flux density, the efficiency can be online optimized at

37、 different speeds and loads. </p><p>　　Fig. 4. Control strategies. (a) DSPM. (b) PMHB.</p><p>　　Fig. 4 shows the control strategies of these two stator-PM motor drives, indicating that the PMHB

38、motor drive has an additional flux controller to regulate the airgap flux. </p><p>　　The pole selection of the DSPM motor drive is governed by the following equations: </p><p>　　N s ? 2mk and

39、 N r ? N s ? 2k （1）</p><p>　　where m is the number of phases, k the integer, N s the number of stator poles, and N r</p><p>　　the number of rotor poles. The pole selection of the PMHB moto

40、r drive is given by: </p><p>　　＝4mp and ＝2Ns/m (2) </p><p>　　where p is the number of pole pairs of the DC field windings.Therefore, when the suitable parameters are selected, namely m= 3, p=

41、 3, and k= 6 , the poles of these stator-PM motor </p><p>　　drives lead to be ＝36， and ＝24 . It can be found that for </p><p>　　three-phase armature windings of the PMHB motor drive, all the

42、 other parameters can be obtained according to the value of p. Hence, the aforementioned equation (2) can be used to simply determine the other possible slot-tooth combination for the PMHB motor drive.</p><p&g

43、t;　　IV. ANALYSIS APPROACH </p><p>　　The CFT-TS-FEM can be used to analyze the steady-state and ransient performances of both machine drives. For each machine drive, the mathematic model consists of three se

44、ts of equations: the electromagnetic field equation of the machine, the circuit equation of the armature windings, and the motion equation of the motor drive. The electromagnetic field equation of both machine drives is

45、given by [7]:</p><p>　　where Ω is the field solution region, v the reluctivity, σ the electrical conductivity, J the current density, A the magnetic vector potential component along the z axis, and an

46、d the PM remanent flux density components along the x axis and y axis, respectively. </p><p>　　It should be noted that for the PMHB machine drive, the DC field current excitation is regarded as a component

47、added together with the PM component as the magnetization. </p><p>　　The circuit equation of the armature windings at motoring is governed by:</p><p>　　where u is the impressed voltage, R the

48、resistance per phase winding, i the phase current, Le the inductance of the end winding, l the axis length of iron core, S the conductor area of each turn of phase winding, and the total cross-sectional area of conduc

49、tors of each phase winding. </p><p>　　The motion equation of both motor drives is given by:</p><p>　　where is the moment of inertia, the electromagnetic torque, the load torque, λ the d

50、amping constant, and ω the mechanical speed.</p><p>　　After discretization, the above three sets of equations can be solved at each step. Hence, the steady-state and transient performance of both machine dr

51、ives can be deduced. Fig. 5 shows the no-load magnetic field distributions of both machine drives. It can be seen that the DSPM machine has a constant field pattern, whereas the PMHB machine exhibits different field patt

52、erns at different field excitations (?350 A-turns, 0 A-turns, and +1000 A-turns). It verifies that PMHB motor drive has the flux</p><p>　　Fig. 5. Magnetic field distributions. (a) DSPM. (b) PMHB with ?350 A-

53、turn. (c) PMHB with 0 A-turn. (d) PMHB with +1000 A-turns.</p><p>　　V. COMPARISON OF MOTOR DRIVE PERFORMANCES </p><p>　　Based on the same peripheral dimensions and the identical outer-rotor con

54、figuration, the two stator-PM motor drives are designed. Their corresponding design data are listed in Table I.</p><p>　　Since the DSPM motor can accommodate more PMs than the PMHB one, its power density is

55、167% of the PMHB one. However, this merit in power density is offset by the high cost of PMs. From Table I, it can be seen that the DSPM motor utilizes the PM volume up to 502% of the PMHB one. Based on the present inter

56、national rates, the PM material cost of the DSPM motor is US$116.3 as shown in Table II, which is much higher than the US$22.3 of the PMHB one. Hence, it leads to the total material cost of the </p><p><b

57、>　　TABLE I </b></p><p>　　PARAMETERS OF DSPM AND PMHB MOTOR DRIVES </p><p><b>　　TABLE II</b></p><p>　　COSTING OF DSPM AND PMHB MACHINES</p><p>　　By

58、using the CFT-TS-FEM, the electromagnetic characteristics of the two motor drives are calculated and compared. Fig. 6 shows the airgap flux density distributions of both motor drives, indicating that the PMHB motor drive

59、 can offer a very wide range of flux control (up to 9 times). Then, the flux linkage of the DSPM machine at full magnetization level is shown in Fig. 7(a), whereas those of the PMHB machine are computed at different magn

60、etization levels with various field currents and shown in</p><p>　　Due to the use of more PMs, the DSPM motor drive can definitely produce higher torque than the PMHB motor one. Nevertheless, as shown in Fig

61、. 8, the PMHB motor drive can utilize flux strengthening to achieve the torque up to 85.7% of the DSPM motor one, even though its PM volume is only 19.2% of the DSPM one. Also, since the PMHB motor drive inherently </

62、p><p>　　provides low airgap flux density than the DSPM motor one while they have a similar tooth-slot structure, the PMHB motor drive can offer significantly lower cogging torque than that the DSPM motor one as

63、 depicted in Fig. 9. It also illustrates that the cogging torque of both motor drives is small due to the use of concentrated armature windings with 36/24 fractional-slot structure. </p><p>　　When the two mo

64、tor drives run in the starting mode, their transient torque responses (normalized by the rated values) are compared as shown in Fig. 10. When they start a load torque of 40 Nm, their armature currents can still be limite

65、d to 2 times the rated value. It can be also found that the PMHB motor drive can produce much higher starting torque in the presence of flux strengthening at 750 A-turn. </p><p>　　When both of the stator-PM

66、machines work in the generation mode, their no-load EMF waveforms at different speeds are shown in Fig. 11. Because of uncontrollable flux, the DSPM machine generates speed-dependent EMF waveforms. On the contrary, the P

67、MHB machine can uniquely achieve constant-amplitude EMFs by the use of flux strengthening at 250 rpm and flux weakening at 1000rpm, which covers all the constant-power speed range of the in-wheel EV drive. Hence, the PMH

68、B machine can keep the constant o</p><p>　　Fig. 6. Airgap flux density distributions. (a) DSPM. (b) PMHB.</p><p>　　VI. CONCLUSION</p><p>　　Two emerging stator-PM motor drives (the

69、DSPM and the PMHB types) have been quantitatively compared. Based on the same peripheral dimensions and outer-rotor 36/24-pole topology, the two motor drives have undergone detailed performance analysis. Compared with th

70、e DSPM motor drive, the PMHB motor drive takes the definite merit of flux controllability, hence achieving better constant-power profile, lower cogging torque, higher starting torque and constant voltage generation over

71、a wide speed range.</p><p>　　ACKNOWLEDGMENT</p><p>　　This work was supported and funded by a grant (HKU 114/06E) from the Research Grants Council, Hong Kong pecial Administrative Region, China.&

72、lt;/p><p>　　REFERENCES</p><p>　　[1] K.T. Chau and C.C. Chan, “Emerging energy-efficient technologies for hybrid electric vehicles,” IEEE Proceedings, Vol. 95, No. 4, April 2007, pp. 821-835. </

73、p><p>　　[2] Z.Q. Zhu and D. Howe, “Electrical machines and drives for electric, hybrid and fuel cell vehicles,” IEEE Proceedings, Vol. 95, No. 4, April 2007, pp. 746-765. </p><p>　　[3] K.T. Chau,

74、 C.C. Chan, and C. Liu, “Overview of permanent-magnet brushless drives for electric and hybrid electric vehicles,” IEEE Transactions on Industrial Electronics, Vol. 55, No. 6, June 2008, pp. 2246-2257. </p><p

75、>　　[4] C.C. Chan and K.T. Chau, Modern Electric Vehicle Technology. Oxford: Oxford University Press, 2001. </p><p>　　[5] Y. Wang, K.T. Chau, C.C. Chan, and J.Z. Jiang, “Transient analysis of a new outer

76、-rotor permanent-magnet brushless dc drive using circuit-field-torque time-stepping finite element method,” IEEE Transactions on Magnetics, Vol. 38, No. 2, March 2002, pp. 1297-1300. </p><p>　　[6] C. Liu,

77、 K.T. Chau, J.Z. Jiang, and L. Jian, “Design of a new outer-rotor permanent magnet hybrid machine for wind power generation,” IEEE Transactions on Magnetics, Vol. 44, No. 6, June 2008, pp. 1494-1497. </p><p&

78、gt;　　[7] S.J. Salon, Finite Element Analysis of electrical Machines, Kluwer Academic Publishers, 1995.</p><p>　　電動(dòng)汽車(chē)外轉(zhuǎn)子定子PM無(wú)刷電機(jī)驅(qū)動(dòng)器的比較

79、 </p><p>　　K.T. Chau1, Senior member IEEE, Chunhua Liu1, and J.Z. Jiang2</p><p>　　1 Department of Electrical and Electronic En

80、gineering, The University of Hong Kong, Hong Kong, China</p><p>　　2 Department of Automation, Shanghai University, Shanghai, 200072, China</p><p>　　摘要 本文兩個(gè)新興外轉(zhuǎn)子定子PM（ PM ）的無(wú)刷電機(jī)驅(qū)動(dòng)器，即雙凸極PM電機(jī)驅(qū)動(dòng)器和P

81、M無(wú)刷電機(jī)驅(qū)動(dòng)器混合，定量地比較，首先，這是特別有吸引力的為電動(dòng)汽車(chē)服務(wù)的輪電機(jī)驅(qū)動(dòng)器。為了使進(jìn)行公平的比較，這兩個(gè)電機(jī)驅(qū)動(dòng)器的設(shè)計(jì)相同的外圍尺寸和基于同樣的外轉(zhuǎn)子36/24極拓?fù)洹＠秒娐吠獾嘏ぞ貢r(shí)步有限元法進(jìn)行分析，他們的穩(wěn)態(tài)和瞬態(tài)性能都比較嚴(yán)格。此外，對(duì)這兩個(gè)機(jī)器的成本分析來(lái)評(píng)估其成本效益。</p><p>　　索引詞 電動(dòng)汽車(chē)，有限元法，機(jī)械設(shè)計(jì)，PM電機(jī)驅(qū)動(dòng)器。</p><p&g

82、t;<b>　　I.導(dǎo)言</b></p><p>　　近年來(lái)，PM（ PM ）的無(wú)刷電機(jī)驅(qū)動(dòng)器已廣泛應(yīng)用于電動(dòng)汽車(chē)（EVs） [ 1-2 ] 。雙凸PM（ DSPM ）電機(jī)驅(qū)動(dòng)和PM混合無(wú)刷（ PMHB ）電機(jī)驅(qū)動(dòng)是兩個(gè)新興定子PM無(wú)刷電機(jī)驅(qū)動(dòng)器，提供較高的機(jī)械完整性和高功率密度，因此適合于電動(dòng)汽車(chē)的應(yīng)用[ 3 ] 。他們的外轉(zhuǎn)子電機(jī)結(jié)構(gòu)是在應(yīng)用于直接驅(qū)動(dòng)的電動(dòng)汽車(chē)特別有吸引力，尤其是服務(wù)于

83、電動(dòng)汽車(chē)的電機(jī)驅(qū)動(dòng)器[ 4 ] 。然而，在文學(xué)作品中，定量比較這兩個(gè)電機(jī)驅(qū)動(dòng)器是不存在的。</p><p>　　本文的目的是以新的方法比較兩個(gè)外轉(zhuǎn)子定子PM無(wú)刷電機(jī)驅(qū)動(dòng)器，即DSPM和PMHB類(lèi)型。基于相同的外圍尺寸，這兩個(gè)電機(jī)驅(qū)動(dòng)器被設(shè)計(jì)成相同外轉(zhuǎn)子36/24-極拓?fù)洹＠秒娐放ぞ亓Σ綍r(shí)有限元法（CFT-TS-FEM） [ 5 ] ，對(duì)電機(jī)驅(qū)動(dòng)的穩(wěn)態(tài)和瞬態(tài)性能都進(jìn)行了比較和分析。此外，還將揭示和討論相應(yīng)的成本效

84、益。</p><p>　　第二節(jié)將介紹電機(jī)驅(qū)動(dòng)系統(tǒng)及其配置。在第三節(jié)中，將比較兩個(gè)電機(jī)驅(qū)動(dòng)器的設(shè)計(jì)和成本效益的。第四節(jié)將討論這兩個(gè)電機(jī)驅(qū)動(dòng)器的分析方法。在第五節(jié)將給出它們的性能的比較結(jié)果，最后將在第六節(jié)得出的結(jié)論。</p><p>　　二.系統(tǒng)配置和運(yùn)行模式 圖1顯示了當(dāng)他們擔(dān)任電動(dòng)汽車(chē)的輪電機(jī)驅(qū)動(dòng)，尤其摩托車(chē)時(shí)這兩個(gè)外轉(zhuǎn)子定子PM電機(jī)驅(qū)動(dòng)器的結(jié)構(gòu)。可以看出，這些應(yīng)用在四輪電機(jī)驅(qū)動(dòng)

85、器有效利用外層空間轉(zhuǎn)子性質(zhì)并以直接與輪胎輪輞形成配套。因此，這些拓?fù)浣Y(jié)構(gòu)可以充分利用電機(jī)驅(qū)動(dòng)器空間和材料，因此大大減少了電動(dòng)汽車(chē)的體積和重量。</p><p>　　圖1 計(jì)劃的電動(dòng)電機(jī)驅(qū)動(dòng)器的拓?fù)浣Y(jié)構(gòu)(a) DSPM. (b) PMHB</p><p>　　這兩個(gè)電機(jī)驅(qū)動(dòng)器配置在圖2和3 中顯示。它可以發(fā)現(xiàn)，它們有類(lèi)似的三相全橋驅(qū)動(dòng)的電樞繞組;而區(qū)別在于， H橋式驅(qū)動(dòng)器應(yīng)用在PMHB電機(jī)驅(qū)

86、動(dòng)的直流場(chǎng)繞組。因此，其工作原理非常相似，除了PMHB電機(jī)驅(qū)動(dòng)的控制場(chǎng)。對(duì)于這種電機(jī)驅(qū)動(dòng)器，當(dāng)氣隙磁鏈隨轉(zhuǎn)子的角度增加時(shí)，正向電流被應(yīng)用于電樞繞組，從而產(chǎn)生了正向轉(zhuǎn)矩。當(dāng)磁鏈減少，負(fù)電流被應(yīng)用，也產(chǎn)生了正向轉(zhuǎn)矩。對(duì)于PMHB電機(jī)驅(qū)動(dòng)，可以通過(guò)調(diào)整雙向直流場(chǎng)電流實(shí)現(xiàn)在線流量調(diào)節(jié)。</p><p>　　當(dāng)這兩個(gè)電機(jī)驅(qū)動(dòng)作為輪電機(jī)驅(qū)動(dòng)器并被安裝在電動(dòng)汽車(chē)，它們運(yùn)行在速度范圍為0 到 1000rpm的三種模式 ，即啟動(dòng)，

87、巡航，以及充電。</p><p>　　????當(dāng)電動(dòng)車(chē)運(yùn)行在啟動(dòng)模式，它在很短的時(shí)間內(nèi)需要高轉(zhuǎn)矩啟動(dòng)或加速。對(duì)于DSPM電機(jī)驅(qū)動(dòng)，因?yàn)槠銹M比PMHB驅(qū)動(dòng)器多，電動(dòng)汽車(chē)啟動(dòng)時(shí)它可以提供足夠高的轉(zhuǎn)矩。對(duì)于PMHB電機(jī)驅(qū)動(dòng)，正向直流電流場(chǎng)與PM激發(fā)場(chǎng)一起將被添加到產(chǎn)生磁場(chǎng)，因此它也能夠提供高轉(zhuǎn)矩來(lái)啟動(dòng)電動(dòng)車(chē)，并在道路上克服阻力和摩擦力。</p><p>　　????當(dāng)電動(dòng)車(chē)下坡或運(yùn)行在制動(dòng)條件

88、下，它就工作在通電模式。在這種模式下，這兩個(gè)機(jī)器可以發(fā)揮機(jī)電能量轉(zhuǎn)換的作用，恢復(fù)或再生制動(dòng)能量為電池模塊充電。此外， 對(duì)于PMHB機(jī)驅(qū)動(dòng)器，它可以充分利用其流量控制能力，保持恒定輸出電壓為電池直接充電，這是比DSPM機(jī)驅(qū)動(dòng)器更靈活的驅(qū)動(dòng)器。</p><p>　　?????當(dāng)電動(dòng)汽車(chē)運(yùn)行在巡航模式，或在穩(wěn)定速度，這些定子PM電機(jī)驅(qū)動(dòng)器將進(jìn)入恒功率區(qū)域。這個(gè)速度范圍通常包括400rpm到1000rpm對(duì)于輪電機(jī)驅(qū)動(dòng)的

89、DSPM。但對(duì)于PMHB電機(jī)驅(qū)動(dòng)，它不僅能有效地延長(zhǎng)其運(yùn)行速度高達(dá)4000rpm這足以涵蓋傳統(tǒng)的速度范圍的要求，而且還可以調(diào)節(jié)其磁場(chǎng)的情況，這可以使電源模塊工作在優(yōu)化運(yùn)行點(diǎn)。</p><p>　　Fig. 2. Configuration of DSPM motor drives.</p><p>　　III.比較電機(jī)驅(qū)動(dòng)器的結(jié)構(gòu)和特征</p><p>　　這兩

90、個(gè)定子PM電機(jī)驅(qū)動(dòng)器的結(jié)構(gòu)如圖2和3所示?？梢钥闯觯麄冇邢嗤耐鈬叽绾拖嗤耐廪D(zhuǎn)子，以及相同的36/24極和電樞繞組。主要的區(qū)別是他們的定子和場(chǎng)激勵(lì)。該DSPM電機(jī)驅(qū)動(dòng)僅僅是被PM機(jī)構(gòu)激發(fā)，它位于定子。但對(duì)于PMHB電機(jī)驅(qū)動(dòng)，它雙層定子和雙激發(fā)。其外層可電樞定子繞組，而其內(nèi)層定子包含PM機(jī)構(gòu)和直流場(chǎng)繞組一起產(chǎn)生的磁場(chǎng)[ 6 ] 。</p><p>　　Fig. 3. Configuration of PMHB

91、 motor drive.</p><p>　　當(dāng)他們作為電動(dòng)汽車(chē)的輪電機(jī)驅(qū)動(dòng)時(shí)，類(lèi)似的結(jié)構(gòu)使他們實(shí)現(xiàn)許多優(yōu)點(diǎn)。 外轉(zhuǎn)子特性可以使機(jī)器直接連接輪胎輪輞，這完全消除了機(jī)械齒輪傳動(dòng)和形成了高機(jī)械完整性。因此，降低了功率損耗，系統(tǒng)并發(fā)癥，以及總成本。 這些馬達(dá)驅(qū)動(dòng)器充分利用整個(gè)空間，這使他們緊湊和有效。他們安排繞組和激勵(lì)定位在定子上，從而導(dǎo)致了強(qiáng)大的外轉(zhuǎn)子。</p><p>　　集中電樞

92、繞組與36/24分級(jí)結(jié)構(gòu)可以縮短磁通路徑和結(jié)束繞組的跨度，從而減少鐵和銅材料。此外，這種繞組的安排可以大大降低脈動(dòng)轉(zhuǎn)矩，它通常發(fā)生在傳統(tǒng)的PM電機(jī)驅(qū)動(dòng)器。</p><p>　　其不同的結(jié)構(gòu)也使他們具有不同的功能。</p><p>　　對(duì)于DSPM電機(jī)驅(qū)動(dòng)，它比PMHB結(jié)構(gòu)簡(jiǎn)單1倍。其控制策略也是更簡(jiǎn)單的。但是，這個(gè)簡(jiǎn)單的結(jié)構(gòu)限制了它的靈活性，因?yàn)樗鼰o(wú)法控制氣隙磁通。</p>

93、<p>　　對(duì)于PMHB電機(jī)驅(qū)動(dòng)，因?yàn)樗浞掷昧穗p激發(fā)的優(yōu)點(diǎn)（包括PM機(jī)構(gòu)和DC場(chǎng)繞組） ，它可以提供靈活的氣隙磁通控制，包括流量加強(qiáng)或削弱。此外，空中橋梁被各個(gè)PM分流，因此放大通量削弱能力。相應(yīng)的勵(lì)磁不可避免地導(dǎo)致更多的功率損耗。然而，這種效率的降低可利用氣隙磁通控制部分地適當(dāng)調(diào)整，高效率可以不同的速度和負(fù)載在線優(yōu)化。</p><p>　　Fig. 4. Control strategies. (

94、a) DSPM. (b) PMHB.</p><p>　　圖4顯示了這兩個(gè)定子PM電機(jī)驅(qū)動(dòng)的控制策略，這表明PMHB電機(jī)驅(qū)動(dòng)擁有一個(gè)額外的流量控制器調(diào)節(jié)氣隙磁通。 DSPM電機(jī)驅(qū)動(dòng)的極選擇是根據(jù)下列方程： </p><p>　　N s ? 2mk and N r ? N s ? 2k （1）</p><p>　　m表示相數(shù)，k為整

95、數(shù)，為定子極數(shù)以及為轉(zhuǎn)子極數(shù)</p><p>　　PMHB電機(jī)驅(qū)動(dòng)的記選擇是根據(jù)下列方程：</p><p>　?。?mp 和 ＝2Ns/m (2)</p><p>　　p表示直流場(chǎng)繞組極對(duì)數(shù)。</p><p>　　因此，當(dāng)選擇合適的參數(shù)，即m=3,p=3,k=6,這些定子PM電機(jī)驅(qū)動(dòng)器極數(shù)＝36，＝24。它可以發(fā)現(xiàn)，PMHB電機(jī)驅(qū)動(dòng)的

96、三相電樞繞組，根據(jù)變量p能計(jì)算出所有其他參數(shù)。因此，上述方程（ 2 ）可以用來(lái)簡(jiǎn)單地確定PMHB電機(jī)驅(qū)動(dòng)其他可能的槽齒結(jié)合。</p><p><b>　　IV.分析方法</b></p><p>　　在電路扭矩力步時(shí)有限元法可以用來(lái)分析機(jī)器驅(qū)動(dòng)器穩(wěn)態(tài)和瞬態(tài)性能。對(duì)于每一個(gè)機(jī)器驅(qū)動(dòng)器，數(shù)學(xué)模型包括三套方程：電磁場(chǎng)方程，電路方程的電樞繞組和運(yùn)動(dòng)方程的電機(jī)驅(qū)動(dòng)。</p

97、><p>　　兩個(gè)機(jī)器驅(qū)動(dòng)器的電磁場(chǎng)方程，如[7]:</p><p>　　其中Ω是場(chǎng)解決區(qū)域，v為磁阻系數(shù) ， σ為電導(dǎo)率，J為電流密度，A磁矢勢(shì)沿Z軸分量，和和分別為PM沿X軸和Y軸剩磁磁通密度組件。應(yīng)當(dāng)指出的是，對(duì)于PMHB機(jī)驅(qū)動(dòng)器，直流場(chǎng)激發(fā)被視為一個(gè)組成部分與PM組件作為磁化部分被添加。 在汽車(chē)?yán)?，電路方程的電樞繞組是下列方程：</p><p>　　其中

98、U是外加的電壓，R是每相繞組的電阻，i是相電流，是T型繞組的自感系數(shù)，l是鐵心的長(zhǎng)度，S是相繞組每次旋轉(zhuǎn)的面積，以及是每相繞組總的橫截面積。</p><p>　　兩種電機(jī)驅(qū)動(dòng)器的運(yùn)動(dòng)方程是下列方程：</p><p>　　其中是慣性力矩，是電磁轉(zhuǎn)矩，是負(fù)載轉(zhuǎn)矩，是阻尼系數(shù)，以及機(jī)械速度。</p><p>　　離散化后，每一步可解三組方程。因此，可以推斷這兩種機(jī)器驅(qū)動(dòng)器

99、的穩(wěn)態(tài)和暫態(tài)機(jī)器性能。 </p><p>　　圖5顯示空載磁場(chǎng)兩種機(jī)器驅(qū)動(dòng)器的分布?？梢钥闯?，該DSPM機(jī)器具有恒場(chǎng)圖，而PMHB機(jī)器展示在不同場(chǎng)的激勵(lì)下不同場(chǎng)圖（ ?350A-turns, 0 A-turns, and +1000 A-turns）。它驗(yàn)證PMHB電機(jī)驅(qū)動(dòng)的流量控制能力。</p><p>　　Fig. 5. Magnetic field distributions. (