Performance Analysis of a Permanent Magnet Brushless DC Motor

Transcription

1 Volume 8 o. 9 08, 5-4 ISS: (printed version); ISS: 4-95 (on-line version) url: ijpam.eu Performance Analysis of a Permanent Magnet Brushless DC Motor UPEDRA KUMAR POTURU * Dr. P.MALLIKARJUA RAO Research Scholar, Department of Electrical Engineering, Andhra University, Visakhapatnam, Andhra Pradesh, India. Assistant Professor, Department of EEE, GMRIT, Rajam, Andhra Pradesh, India. Professor, Department of Electrical Engineering, Andhra University, Visakhapatnam, Andhra Pradesh, India. Author id: upendrakumarpotnuru@gmail.com Abstract: The main goal of the present paper is to analyze the execution of a permanent magnet brushless DC motor. Utilizing a general radial flux motor concept, the design is refined through the counts by remembering the confinements of the machine. A few magnetic circuit adjustments have been considered and the paper shows the aftereffects of the most sensible arrangements, getting critical augmentations of the power. This paper shows a conservative brushless permanent magnet (BLDC) motor design for those brief span operations. Plan systems for both inside and outside rotor BLDC motors are portrayed. This paper displays the conceivable mixes of slots and poles, winding coefficient which decides the motor execution, winding configuration for three-phase brushless dc motor and plan estimations for a specific application. Keywords: BLDC Motor, Flux, Design, Winding, Specifications.. Introduction Electric motors are wherever on the planet today. The world as we probably are aware it exists given electric motor. From the earliest starting point motors have been utilized to enhance the regular day to day existence of individuals on earth. Starting today, there are around 0 sorts of DC and AC motors that all effectively convert electrical energy to mechanical energy. Out of these brushless DC motor is picked given their higher sturdiness because of effortlessness in outline and fast capacities. BLDC motors are known for high torque, reliability and sturdiness [-]. These are having long lives and once in a while fizzling. The cutaway view of brush less DC motor appears in figure. 5

2 Fig.. Cutaway view of BLDC motor at all like brushed motors where each motor phase is opened and closed mechanically, a brushless motor needs an electronic controller to change the phase of a motor. The hardware is genuinely easy to make and can be brought given that a wide range of sorts of controllers are accessible. Picking a brushless design permitted more choices and considered less demanding assembling of the motor []. There are two fundamental sorts of BLDC motors are there. They are radial and axial flux motors as appeared in figure.. Fig.. Radial and Axial flux view of a BLDC motor The difference between them is the direction of flow of flux. Fig. indicates the design layout of slots and 4 poles of a permanent magnet BLDC motor. These outlines are commonly utilized for different applications like fans, remote control plane motors, water pump motors and so on [4]. The most difficult part is the design of a stator since design itself made windings hard to wind. With this specific design, the rotor configuration can be changed if essential. 6

3 Fig.. Design of radial flux motor with Slots and 4 Poles The general shape/design for the motor has been built up the sort of material going to be utilized should be found. Fig.4 demonstrates a magnetic field strength versus flux density [5]. Fig.4 Typical magnetization curve for permanent magnets With greater flux, there is more prominent magneto motive force, which basically brings about greater magnetic field strength. The objective is to maximize the flux. Keeping in mind the end goal to augment the flux, the more flux density is required [6]. The more prominent the magnetic field, the more grounded compel the magnets must be pulled in or repulsed. By and large, the material must be discovered that was sensibly evaluated and could give the 7

4 4 coveted flux density. Fig.5 demonstrates the winding scheme of slots and 4 Poles BLDC motor. Fig.4 The winding layout of Slots and 4 poles BLDC motor.. MATHEMATICAL MODELIG TO DETERMIE MOTOR RATIGS AD DIMESIOS... Selection of Slot number for a given number of poles To determine dimensions and ratings the following equations are used. B = µ H () Where B is maximum flux density H is magnetic field Intensity Μ is the permeability of the medium Force is given by 8

5 5 F = φr () Where R is reluctance Torque is given by T = KD L () Where K is motor constant D is the diameter L is the length Reluctance is given by R = (4) µ A Where A is the area of cross section Flux is given by I φ = (5) R Maximum flux density is given by B = B + µ µ H (6) m r 0 r m Where B r is the flux density of rotor. Flux of the permanent magnets is given by = B A = B A + A H (7) φ µ µ m m r m R 0 m m Flux linkage of the coil is given by λ = i (8) R Induced voltage is given by d( Li) di dl e = = L + i (9) dt dt dt Torque equation is given by dl dr dφ T = i φ + i (0) dθ dθ dθ Inductance of air gap is given by πµ 0Lst Rro Lg = () lm g + K m µ RC φ B L R I B L R B R = = = V () g st ro g st ro g ro I ( R ) ρlst / A slot wb ρ Cogging Torque is given by wb 9

6 6 T Cog dr dθ = φ () Ultimately from the above equations the determination of motor dimensions is. Several other factors like springing effect, Proximity effect and effect of eddy current are need to be accounted before the construction of the motor [7-8]... Performance Analysis The SPP/P, KW and umber of symmetries () combinations of a various number of poles and number of slots have been analyzed for a particular motor [9]. The possibility of the combinations along with the design parameters like, and are presented in table. P S Remarks Table. Performance analysis of machine for various slots and poles combinations 40

7 7.7. Summary/Conclusion This paper shows the design and performance information of machine for the direct-drive impetus framework. The machine has been particularly intended to meet the prerequisites. From the above analysis, the distinctive quantities of slots and poles combinations are resolved. In the event that the number of slots is near number of poles then the motor execution will be more efficient, i.e. (s = p±; s = p±; s = p±). The Winding coefficient is the performance indicator of a motor. If the winding coefficient is more the motor performance will be more effective. The scope of winding coefficient is or less than. When all is said in done for a BLDC motor one can incline toward fractional-slot concentrated winding. So as to have adjusted winding the EMF magnitude, shape and relative phases of all stages must be met. References: [] Sheldon S. Williamson, Ali Emad and Kaushik Rajashekara, Comprehensive Efficiency Modeling of Electric Traction Motor Drives for Hybrid Electric Vehicle Propulsion Applications, Vol. 56, o. 4, PP.56-57(007). [] Yee-Pien Yang, Yih-Ping LuH, Cheng-Huei Cheung, Jui-Ping W m G, Shang-Wei wu, Multi-Objective Optimal Design and Current Waveforms Control of Axial-Flux Brushless DC Wheel Motors for Electric Vehicles,PP.6-66 (00). [] Yee-Pien Yang and Down Su Chuang, Optimal Design And Control of wheel motor for Electric passenger cars, Vol 4, o., PP. 5-6 (007). [4] Khwaja M. Rahman,, itin R. Patel, Terence G. Ward, James M. agashima, Federico Caricchi, and Fabio Crescimbini, Application of Direct- Drive Wheel Motor for Fuel Cell Electric and Hybrid Electric Vehicle Propulsion System, Vol 4, o. 5, PP.85-9 (006) [5] Gyeong-Chan Lee and Tae-Uk lung, Design Comparisons of BLDC Motors for Electric Water Pump, PP. 48-5,( 0). [6] Suyongkim, Ju Hee Cho, Byung Taek Kim and Julee, ovel Spoke-Type BLDC Motor Design for Cost Effective and High Power Density, PP. 90-9,(06). [7] Hyeon-MyeongYang, Jin-Wook Cha, Bok-Hyun Baik and Byung-il Kwon, Design and Analysis of High Speed BLDC Motor for Centrifuge, PP ,(05). [8] Y.K. Chin, W.M. Arshad, T. Backstrom & C. Sadarangani, Design of a Compact BLDC motor for Transient Applications, PP ,(05). [9] Young-Kyoun Kim, Se-hyun Rhyu, and In-Soung Jung, Reduction Design of Cogging Torque of BLDC Motor for EPS Application, PP. 7-,(00). 4

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