<4D6963726F736F667420576F7264202D20312D313520CCE3C7E120E6DDD1CC20E6D1DBCFC7C1> Al-Khwarizmi Engineering Journal Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, Sptember, (2019) P. P. 1- 15 Design and Optimization of a Surface-Mounted Permanent-Magnet Linear Synchronous Motor with Maxwell ANSYS Jamal Abdul-Kareem Mohammed* Farag Mahel Mohammed** Raghda'a Ahmed A. Ali*** *,**,***Department of Electromechanical Engineering/ University of Technology/ Baghdad/ Iraq *Email: 50128@uotechnology.edu.iq **Email: drfaragmahel@yahoo.com ***Email: gadaahmad460@yahoo.com (Received 1 August 2018; accepted 28 January 2019) https://doi.org/10.22153/kej.2019.01.005 Abstract Linear motor offers several features in many applications that require linear motion. Nevertheless, the presence of cogging force can deteriorate the thrust of a permanent magnet linear motor. Using several methodologies, a design of synchronous single sided linear iron-core motor was proposed. According to exact formulas with surface-mounted magnets and concentrated winding specification, which are relying on geometrical parameters. Two-dimensional performance analysis of the designed model and its multi-objective optimization were accomplished as a method to reduce the motor cogging force using MAXWELL ANSYS. The optimum model design results showed that the maximum force ripple was approximatrly reduced by 81.24%compared to the original model with a smaller ripple coefficient of 0.22. Likewise, the model was redesigned taking into consideration two cases; laminated core and solid core. It was found that the error between the analytical and numerical results of the output force did not exceed 0.0967%. Keywords: ANSYS, cogging force, linear motor, optimal design. 1. Introduction Permanent magnet linear motors (PMLMs) are used in wide industrial applications; particularly for high positioning accuracy of concerned implementations. The linear motors (LMs) are mainly based on the electromagnetic concept where they delivere direct linear movement without using gears, cams, belts or other mechanical accessories. This is when the mechanical motion synchronizes the magnetic field. The PMLSMs can be classified into categories: flat or tubular, single sided or double sided, slotted or slot-less, air cored or iron-cored, and longitudinal flux or transverse flux. The LM consists of stator and the translator. Since, it can present direct linear motion with no need for any rotation to translation conversion of equipment; this leads to simplifying system structure and improving system efficiency [1]. On the other hand, the more predominant nonlinear effect of linear motors is force ripples (detent and reluctance forces) [2]. The detent (or cogging) force is generated by the attraction of the magnets to the LM's core. This force is produced even the winding current is absent. The force demonstrates a periodic relationship with regard to the position of the translator relative to the permanent magnets (PMs) mounted on the stator [3]. Moreover, the reluctance force is generated by the mutation in the winding self-inductance with respect to the position between the translator and stator [4, ٥]. Hence, the cogging forces generally cause an undesired vibration and noise; depending on the thrust magnitude [6]. In order to minimize the force ripple, different methods in the literature were developed. One of the most effective methods is the arrangements of Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 2 the PMs. Thus, it must be optimized to reduce the cogging force, which is more effective than reluctance force as represented by Lim et al. [7]. Also, the method could be conducted by adding some parts as presented by Baker et al. [8]. It's found that adding a Flux Gathering Ring (FGR) to the outer stator teeth of a linear tubular generator could be an effective method to reducing the end effect. Hence, the cogging reduction happens as resultant. Chung et al. [9] proposed designing and analyzing a flux reversal linear synchronous motor (FRLSM). Three various design parameters were investigated and compared in motor characteristics e.g, back-EMF, detent force, normal force, thrust, and phase inductance by using Maxwell ANSYS. The investigation greatly showed low force ripple and good thrust force linearity via PMs' skewing and three-phase sinusoidal control. Cao et al. [10] investigated the effect of some leading design parameters (mover tooth width, the slot open width the width of the slot under PM, mover height and the motor stack length) on the force performance of a complementary and modular linear flux-switching permanent-magnet (LFSPM) motor. That is using finite element method (FEM). Jalal et al. [11] presented the FEA optimization techniques followed by development of a Matlab/Simulink model to investigate the effects of electrical machine inductance and the combined electromagnetic loading of the machine on the resulting force and cogging force. Palomino et al. [12] proposed a technique to combine the FEM and the statistical regression, which permit to implement the optimal skew angle of the PM. That causes a greater reduction of force ripple with the minimum thrust diminution. Ghasime [13] adopted a magnet segmentation method to reduce the cogging torque. Wheras, each surface PM was split into eight parts with symmetrical structure and equal angular widths. The angular gaps between them were utilized for reducing a number of optimization parameters. Lazov and Uzunov [14] used two methods to reduce the detent force in one innovative PMLSM for 2D laser marking system. Two additional end teeth with chamfers in the magnetic circuit of the movable part were used while the other method modified the teeth of the ferromagnetic core with different lengths. This paper suggests an optimization method to estimate the optimum dimensions of the PMLSM based on regular steps with the aid of the Maxwell ANSYS simulation. The optimum dimensions required are the magnet length, magnet width, magnet height, air gap length, motor length at z- direction and the motor ends' width. 2. Design Procedure The PMLSM is a linear motor where the mechanical motion is synchronizing the magnetic field. The PMLSMs can be classified into flat or tubular, single sided or double sided, slotted or slot-less, air cored or iron-cored, and longitudinal flux or transverse flux. In this paper, the design of a single-sided PMLSM with slotted armature core and surface PMs is proposed. A structure model of a three-phase flat type single sided PMLSM according to the MAXWELL ANSYS is depicted as in Fig. (1). 1. Slotted armature core, 2. Surface PMs, 3. Three-phase windings, 4. Yoke,5. Dummy slot. Fig. 1. 3D model of the proposed PMSLM. Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 3 The core is composed of 13 slots and 13 teeth, 12 slots are filled with single layer concentrated three phase coil windings in a laminated 1010 steel core [15] as a solid core. Each phase in the motor has four slots. These magnetic cores may be made of thin laminations in order to minimize the eddy currents flowing through them. As for all electrical machines, the core losses are composed of hysteresis losses and eddy current losses. The specifications of PMs (NdFeB, Class N42SH) [16] used in the motor design are listed in Table 1. Table 1, NdFeB Permanent Magnet Specifications. B(mT) H(kA/m) BH_max(kJ/m3) Tmax( oC) 1280-1320 >= 1672 320-343 150 Generally, thrust production in the PMLSM is restricted by electrical and magnetic sources. Electrical source depends on the motor coils current. According to Lorentz law [17]: �⃗ � ��⃗ � ��⃗ (vector version) and F= IBL sinθ (strength only) ...(1) at the same time, for magnetic components, the magnetic flux density and inductance effect on the thrust. While the flux of the PMs and coils effect on the magnetic flux density and inductance. This leads to generate a sequence of attracting and repelling forces between the salient poles and the PMs, expressed by a thrust force in the translator [18]. Fig. 2 depicts the working principle of the designed linear motor. Fig. 2. Working principle of a three-phase PMLSM [19]. As the armature moves, an EMF is induced in the stator windings. By differentiating the PM flux of the phase winding with time, a no-load rms voltage Ef is excited. Ef is excited by the PMs' flux and induced in each phase of the armature winding, it can be given as [17]: � 2� ����� …(2) Where: � � � ��� ���������ℜ� ℜ��⁄ ! ⁄ " ���� " ���ℜ��/ℜ�� $� ℜ��⁄ %& !'"&( …(3) ) � 1 + �ℜ�� ,2 ℜ- ./ +0.5 ℜ�3 4 …(4) � � 2)ℜ5 + 2 6- ./ +0.5ℜ�3 …(5) 7 � 2ℜ89 + 0.5ℜ�3 …(6) : � 1 + 4 ℜ�ℜ�� + ℜ<= ℜ�� …(7) The magnetic circuit of an LSM with surface PMs as illustrated in the equivalent magnetic circuit is shown in Fig. 3. Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 4 Fig. 3. Equivalent magnetic circuit of a LM with surface PMs [17]. While, the magnetic flux linked with the armature winding may be given as: � � � ������������ℜ� ℜ��⁄ (" ���� " ���ℜ��/ℜ�� $� ℜ��⁄ %' !'"&( …(8) The relation between the velocity and frequency represented by [17] υs= 2τƒ …(9) The frequency could be estimated using Eq. (9), is found to be equal to 17.36Hz. That is according to the parameters listed in Table 2 with the following design parameters: Fmax = 350N mtranslator ≈ 6.6kg mload = 17kg υmax = 1m/s amax = 1.5m/s 2 Table 2, LM base line design parameters [20]. Lm (mm) ττττ (mm) ⍵⍵⍵⍵p (mm) 288 28.8 24.32 Based on these dimensions and assuming initial teeth lengths and PM volume followed by applying a special algorithm with multiple iterations to obtain the final main design dimensions of the PMs and the geometric dimensions of a single stator slot illustrated in Fig. 4. In the case of using semi-closed slot in the stator core, the detent force depends on the slot aperture width because of the minimizing effect on the slot harmonic components [21]. Fig. 4. Dimensions in mm of a single stator slot. The armature winding resistance as a function of the winding parameters, dimensions, and electric conductivity can be represented by [17]: ?� � � $@´₁ C/D " E/F% G₁ H IJ₁KJKL …(10) In the case of salient pole synchronous motor, the d-axis and q-axis synchronous reactances, respectively can be expressed as: MNO � M� + MKO and MNP � M� + MKP …(11) Here, X1 = 2�fL1 is the armature leakage reactance, and Xad and Xaq are the d-axis and q- axis armature reaction reactance’s, respectively [21] which are calculated as follows: MKO � � O MK � 4Q�RS $G/TJ/%< UV W @X 5´ � O …(12) MKP � � P MK � 4Q�RS $G/TJ/%< UV W @X TYCZ�-[ 5[ � P …(13) Where \´ ≈ �' N̂K_ \ + ℎ9 Raab3⁄ is the d-axis equivalent air gap, Ksat>1 I and Ksatq≈ 1. Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 5 Demagnetization curve of the PM is sensitive to temperature changes. Both Br and Hc reduce as the magnet temperature elevates [17]: �a � �3�c[1 + ef �cc $g89 − 20%]and i3 � i3�c[1 + ej�cc $g89 − 20%] …(14) Where Bc20 and Hc20 are the flux density and coercive force of the PM at 20oC, and k&< 0 and kl < 0 are the temperature coefficients in %/oC for Br and Hc, respectively. The relative recoil magnetic permeability at PM temperature g89of 50oC can be calculated as: Raab3 � &m nol= …(15) Where µ rrec = 1.161. The following equations are the rms d-axis and q-axis armature currents as a function of V1, Xsd, Xsq, R1, Ef, and δ as shown in Fig. 5. �KO � p/�qZ[ 3SNr –t/ Nuvr � wxqZ[ qZ� qZ[ " t< and �KP � p/$t/ 3SNr –qZ� Nuvr%� wxt/ qZ� qZ[ " t< …(16) �K � y�z{� + �z|� …(17) Fig. 5. Full phasor diagram of a LSM [14]. The peak line current density of the armature or the specific electric loading is determined as: )} � }/√� G/�� VW …(18) The input power Pi delivered to the armature winding is given by: �u � Q����K cos ∅ …(19) The copper losses in the core windings is: �∆�� � Q��z�?�. The electromagnetic power (Pelm) and thrust force (Fdx), respectively can be given as [17,22]: �bE} � }/[p/$t/3SNr"qZ�Nuvr%�wxt/] $qZ�qZ[ "t<%< � ����MNP ���� − ?���� �MNO −MNP + �MNO MNP + ?� − MNP �MNO − MNP � …(20) �O� � 8F�� �Z …(21) So, theforce ripple coefficient kr could be calculated by [23]: kr = $�}K�� �}uv% �K�b …(22) 3. Finite Element Simulation A. Solving and Post-Processing Finite element method is one of the most accepted and widely used tools for the solution and optimization of linear and nonlinear partial differential equations [24]. In the current work, the analysis was performed using MAXWELL ANSYS that ignored end windings due to using 2D model. The structure parameters of the motor were presented. The solution was divided into two stages, load and no-load transient magnetic solution. Time-stepping FEA method depending on Maxwell equations was applied for analyzing and optimizing the magnetic and force characteristics of the LM. In the process of solving nonlinear transient magnetic problem, the calculated values of voltage V1 is 45V (at load) and frequency f= 17.36Hz, whereas the solution would be divided into 36 steps with 0.0016sec time period at 0.0001 nonlinear residual using backward Euler time integration method. Mover mesh of the original motor is illustrated in Fig. 6 where the mesh should be dense enough to minimize the error calculation, whereas the model was designed with three regions of meshing. Each region contains 1200 elements. Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 6 Fig. 6. Mover mesh of one region, 4 slots (x & y are the length and the height of the stack, respectively) at position = 4.5mm with respect to the stator, time = 0.0045 sec from initial position. B. Magnetic Field Distribution On no-load case, considering the axial symmetry of the PMLSM, the designed motor was simplified to a 2D axial symmetry model in Cartesian coordinates ignoring core losses. An irregular distribution of the current density in the conductor was considered. The distribution of the magnetic lines is depicted as shown in Fig. 7. Various shades of rainbow color denoted magnetic flux density values at time equal to 0.0032 sec plus the leakage flux inside the slots was clearly noticed. Fig. 7. Distribution of linkage magnetic field lines as closer section with the leakage magnetic field lines (x: motor height, y: reaction rail (yoke) length). Furthermore, the instantaneous PM flux linkages and induced back emf waveforms at no- load magnetic field solutions were obtained as shown in Figs. 8 and 9, respectively. It was observed that the waveform of the flux linkage was approximate sinusoid. Since there was no harmonic magnetic flux, which might be induced by the current at the load case. The PMs flux waveforms were three phase symmetrical, i.e. they had the same magnitude with 120 electrical degrees shifting. This is a fundamental requirement of three-phase motor design. Unlike the flux linkage, the back emf has irregular sinusoid. Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 7 Fig. 8. 3-phase flux linkage waveforms of the original designat no-load case. Fig. 9. 3-phase induced back emf waveforms of the original design at no-load case. Figure 8 shows that the maximum value of flux linkage on one coil is ≈ 0.46Wb, while the rms value of the back emf, Ef is about 34.63V. Considering that the phase winding consisted of one active coil at any instant. The comparison of values above with the analytical calculations where the PM flux was Φf = 0.4508Wb (Eq. (3)) and the back emf, Ef= 34.3V (Eq. (2)) shows small error between them. Representation of the magnetic field density graph can be illustrated in Fig. 10. It can be noticed that the flux lines move in the transverse direction forming closed loops between each other. Fig. 10. Magnetic field density as a vector in air-gap, core, back-iron along with magnet at position = 4.5 mm, time = 0.0045sec from initial position. Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 8 C. Simulink Design Optimization of the PMLSM Model with and without Core Losses Figure 11, shows the PMLSM model's thrust force at load moving 2� distance to +x direction and the armature current waveforms for the original model with three-phase AC voltage source, neglecting the core losses of the laminated core. The thrust force with rms value was found to be 350.3387N (with 0.9176 ripple coefficient) at Ia≈4.32A. The thrust ripple depended on the field harmonic produced by the magnets (in the air gap) in addition to current harmonics. (a) (b) Fig. 11. The simulation results; (a) thrust force,(b): 3-phase currents. The optimization was accomplished based on the model in Sec. 2. Fig. 12, shows the results of two cases based on MAXWELL ANSYS analysis to predict best dimensions that lead to minimum cogging force at no load case. In Fig. 12-a, the analysis was accomplished based on Table 3-a (first design). the analysis has shown that the maximum cogging force was decreased by 73.9%. Fig. 12-b presents the second design results, which were done with another set of constant values. The cogging force results have decreased by 77.43%.The second design gave the best percentage value of the cogging force reduction. Fig. 12-c represents the ends widths effect on the cogging forces varation of second design at constant values of (em=5, g=1.5 and hM=3) with ends width of Table 3-b. The results showed that, using 2.5mm end length led to 81.24% reduction in cogging force. Table 3, (a) Fist case and (b) Second case of optimization procedure (All dimensions in mm). (a) Parameters Iterations g1 hM ωp&L´1 First 1 5 24.32 - 95 18.66 - 95 12.32 - 95 24.32 - 85 18.66 - 85 Second 1.5 3 12.32 - 85 24.32 - 75 18.66 - 75 12.32 - 75 (b) One of the ends length em (Iterations) Constant Parameters 0.25 g1 = 1.5 1.4375 hM = 3 2.625 ωp = 12.32 3.8125 L´1 = 75 5 LM = L´1 = 75 Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 9 (a) Cogging forces at constants (em=5, g =1 &hM=5) mmwith different values of ⍵⍵⍵⍵p&L´₁₁₁₁. (b) Cogging forces at constants (em=5, g=1.5 &hM=3) mm at different values of⍵⍵⍵⍵p &L´₁₁₁₁. (c) Cogging forces at diffirent ends widths with best dimentionsof step (b); (g=1.5, hM=3, ⍵⍵⍵⍵p=12.5 &L´₁₁₁₁=75) mm . Fig. 12. Best dimentions of the optimum value of the cogging force. Table 4 clarifies the orginal model dimensions and parameters plus the optimum design results from the steps above. That is to find the optimum output thrust as illustrated in Fig. 13 for the load case using MAXWELL ANSYS. The rms value of the output force was found to be equal to 320.4833N at the mean value for the rms motor currents of Ia =3.555A. The output force might be equal to 320N at mload = 17kg and optimum mtranslator ≈ 4.75kg. It could be seen that the thrust ripple reduced effectively for the optimal designed motor case. In fact, the optimized motor suffered from thrust ripple twice less than that for the original model. Therefore, the rms input voltage of three phase had to be increased by 11.56V to compensate the lost thrust caused by reducing the PM volume. Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 10 Table 4, The major dimensions and parameters of the two design models; calculated and optimal. (a) Thrust force as a function of time at rms current = 3.555A with optimum parameters. (b) 3-phase of 2D simulated currents with optimum parameters. Fig.13. Motor performance with optimum parameters. Symbols Dimensions and parameters Quantities Calculated Optimum Pin Input power (W) 402.7 411.21 V1 Rated voltage (V) 45 56.568 Ia Armature current (A) 4.3 3.555 f Magnetic field frequency 17.36 17.36 N1 Number of turns of coil winding/phase 280 480 g1 Air gap length (mm) 1 1.5 em One of the ends length (mm) 5 2.5 R1 Armature winding resistance/phase (Ω) 0.95 2.48 L´1& LM Length of the laminated stack at z direction (mm) 95 75.2 dw Diameter of copper wire (mm) 1.3 0.95 ωp PM width (mm) 24.32 12.5 hM PM height (mm) 5 6 hc2 Stator height (mm) 8 8 X1 Armature leakage reactance (Ω) 1.8723 …. Xad d-axis synchronous reactance (Ω) 1.0228 …. Xaq q-axis synchronous reactance (Ω) 0.86023 …. Kw Winding factor [25] 0.966 …. Δ Load angle (degrees) 8.85 …. ∆Pcu Copper losses (w) 52.7 91.21 Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 11 The core loss could affect the machine flux linkages. As these measurements were done at low speed, consequently the core loss component was sort of small where it was equal to (25.568W) as shown in Fig. 14-a and the output force at Fig. 14-b was (253.4N) at mean value of the rms motor currents of Ia = 5.29 A. Therefore, errors in the flux linkage computation were small since magnetic losses were caused by harmonic main flux and harmonic leakage flux [26]. (a) (b) (c) Fig. 14. (a) Iron losses of optimum solid core, (b) Output thrust in this case and (c) 3-phase currents. Thrust force constants, force ripple coefficient and the efficiency percentage [27] results are illustrated in Table. 5. The greater value of the force constant (kF = Fdx/ Ia) [28] led to least thrust ripple krand highest efficiency which represented the best model. Variant results were observed in the model's kF-RMS values. This disparity was located due to a few reasons whereas two of them Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 12 were convergent unlike the rest. The convergence of the first two models' values was related to the error between the exact and the analytical equations. While the increment of the third model was due to applying the optimization method to enhance the performance, which is the goal of this paper. On the other hand, loss consideration in the fourth model caused the kF-RMS value to decrease. However, the ripple coefficient was equal to 0.319 that was considered an acceptable value to the practical designs in comparison with rest of the models that contain high efficiency or better ripple coefficient but remain a virtual design. Table 5, Force constant values, ripple coefficient, and efficiency models kF-Max (N/A) kF-Min(N/A) kF-RMS(N/A) Ia(A) kr Efficiency % 1-Analytical model …… …… 81.395 4.3 …… 86.91 2-Simulated model 129.65 59.814 81.096 4.32 0.93 86.92 3-Optimal model 108.257 88.963 90.15 3.555 0.22 77.82 4-Optimal model with losses 58.631 43.73 47.845 5.2962 0.319 64 4. Conclusions Towards enhancing the performance of the single sided PMLSM, a primary structure of 10/12 pole-slot three phase synchronous single-sided linear motor has been designed and modeled using 2D FEA simulation whereas a Maxwell ANSYS has been employed. The following conclusions can be presented: 1. The design achieves optimum motor performance with minimum thrust ripple coefficient of 0.22 and thrust force of 320.4833N at rms load current of 3.555A wherekF-RMS of 90.15. 2. The optimized motor gives a thrust ripple twice less compared to the original model. 3. Some loss of thrust force is caused by the reduction in the PMs volume. 4. The core losses are introduced as a second case with a laminated core for the optimum model producing a thrust ripple coefficient of 0.319 and thrust force of 253.4 N at rms load current of 5.2962A where kF-RMS of 47.845. 5. The analytical model and numerical simulations results show a good agreement with maximum error not exceeding 0.0967%. Notation A, B, C, D constants based on magnetic circuit of an LSM with surface PMs amax motor acceleration at the starting ap the number of parallel current path aw the number of parallel conductors B magnetic field density BH_max maximum energy production Fad the d-axis armature reaction MMF Fave , Fmin average output thrust and minimum thrust, respectively FM the equivalent MMF produced by one pole of the PM Fmax , Fdx thrust force f the input motor frequency \q the q-axis air gap length H magnetic field strength hM PM heightof a single pole K1R the skin effect coefficient Ksat the saturation factor of the magnetic circuit Ksatq the saturation factor in the salient pole excitation system kC the Carter's coefficient for the air gap kw the armature winding coefficient L´₁ the laminated stack length Li the stator core effective length LM PM Length Lm motor length l1e the mean length of a single end connection m1 the number of motor phases mload load mass mtranslator translator mass N1 the number of stator winding turns Q1 the number of slots per pole ℜ�3 the reluctance of the armature core (yoke) per pole pitch ℜ�3 the reluctance of the reaction rail core (yoke) per pole pitch ℜ5 the reluctance of the air gap ℜE5 the reluctance of the air gap leakage flux ℜE} the reluctance for the PM leakage flux ℜ89 the reluctance of the PM ℜ_ the reluctance of a single tooth Sw1 the armature conductor cross Jamal Abdul-Kareem Al-Khwarizmi Engineering Journal, Vol. 15, No. 3, P.P. 1- 15 (2019) 13 section Tmax maximum working temperature υmax motor velocity Greek letters δ the load angle between the terminal motor phase voltage V1 and Ef Φf the magnetic flux produced by the PM ∅ the motor power factor angle, the phase angle between V1 and Ia ØA, ØC, ØC the magnetic flux of three phases A, B and C, respectively ⍵p PM width θ the angle between the field direction and the conductor direction µ o the free space magnetic permeability σ the electric conductivity of a conductor at an operating temperature τ pole pitch 5. 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Fang and Y. Ye, ''Performance of Partitioned Primary Linear Switched Flux PM Machines,'' IEEE, pp.2486-2491, 2016. )2019( 1- 15، صفحة 3، العدد15دجلة الخوارزمي الهندسية المجلم جمال عبد الكريم محمد 15 على َبتتَصميم وتحقيق التصميم االمثل للمحرك الخطي التزامني ذو المغناطيس الدائم الُمثّ السطح باستخدام برامج ماكسويل أنسزز ***علي رغداء أحمد عبد فرج محل محمد** الكريم محمد*جمال عبد العراق /قسم الهندسة الكهروميكانيكية / الجامعة التكنولوجية / بغداد*** ،**،* 50128@uotechnology.edu.iq:البريد االلكتروني * drfaragmahel@yahoo.com :البريد االلكتروني ** gadaahmad460@yahoo.com :البريد االلكتروني *** الخالصة ب المغناطيسية التجاذالتي تتطلب حركة خطية. على الرغم من ذلك ،فإن وجود قويزات في العديد من التطبيقات ميوفر المحرك الخطي العديد من الم تزامن أحادي ك خطي مالتي تشابه قوى الترس الميكانيكية يمكن أن يتسبب في تدهور قوه الدفع في محرك خطي ذي مغناطيسي دائم. لذلك تم تقديم محر ت رات المتغيرالى تأثيبوجود اللف المتمرّكز وتمثيله طبقا لصيغ الدفع التحليلي مستندة ع الجانب في هذه الورقة مصمًما بمغناطيس مثبت على السطح ه الظاهرةلتعامل مع هذلنهجيات . تبعا لذلك، تم تنفيذ العديد من الممالهندسية مثل، تشكيلة اخدود الملف، طول الفجوة الهوائية، وارتفاع المغناطيس الدائ رك ة التجاذب المغناطيسي للمح) للنموذج المصمم والتحسين متعدد األهداف الخاص به طريقة لتقليل قو٢Dداء ثنائي األبعاد (يتم انجاز تحليل األالمؤذية. مقارنة % ٨١٫٢٤ . تُبين نتائج تصميم النموذج المثالي بأّن التموج الحاصل في قوة الدفع القصوى تقل بحواليMAXWELL ANSYSباستخدام برنامج ن؛ القلب المرّقق (ذو . أيضا، تّم أخذ خسائر القلب الحديدي بنظر االعتبار ولحالتي٠٫٢٢ألصلي (قبل التطوير) وبأصغر معامل تموج هو مع النموذج ا في المحرك ةلدفع الخارجااب قوة الشرائح) والقلب الُصلب وقُورنت النتائج في الحالتين. لقد وجد بأن خطأ نتائج التصميم بين الطرق التحليلية والعددية لحس .٠٫٠٩٦٧ال تتجاوز