Radial Flux Generator Research Articles

Simplified design of low speed electric permanent magnet generator for small wind power plant

Wind power plant is one of the renewable energy where energy utilization is ± 3-5% from potential existing of wind power. Wind power plant requires a generator to convert mechanical energy into electrical energy, mostly the generators available in the market is a kind of high speed induction generator which requires high rotational speed and an electricity to generate a magnetic field. While in wind power plant needs low speed generator and without initial electricity. Hence, a radial flux generator is designed in this project to have low speed rotation using permanent magnet type Neodymium Iron Boron (NdFeB). Finite Element Method (FEM) Magnet software is used for designing the generator model. Several modifications are applied to get optimum result by changing generator diameter, number of coils, the copper wire diameter, number of poles, and used slots. The simulation results obtained generator speed 500 rpm, the average series voltage is 185.44 Volt. Generator requires 18 cm diameter, number of turn for each coil is 55, diameter of the copper wire used is 0.6 mm, and number of poles is 8 pairs and 12 unit slots.

A Design of Electrical Permanent Magnet Generator for Rural Area Wind Power Plant

<p>This paper aims to design and simulate an Electrical Permanent Magnet Generator (EPMG) for rural area wind power plant. The generators available in the market mostly are a kind of high speed induction generator which requires high rotational speed and an electricity to generate a magnetic field. In this project, a radial flux generator is designed to have a low speed rotation using permanent magnet type Neodymium Iron Boron (NdFeB). Software used for designing is Finite Element Method (FEM) Magnet software basis. The model also examined with Simulink/Matlab environment. Extensive modifications are applied to get optimum result by changing generator diameter, number of coils, the copper wire diameter, number of poles, and used slots. The simulation results obtained generator speed 500rpm, the average series voltage is 145 Vrms, the generator requires 18cm diameter, number of turn for each coil is 55, diameter of the copper wire used is 0.6mm, and number of poles is 8 pairs and 12 unit slots.</p>

풍력발전기용 축방향 영구자석 발전기의 코깅 토크 저감을 위한 최적설계

Among the wind power generators, the axial permanent magnet generator has an advantage for increasing the power per unit volume compared to the existing radial flux generator. In this study, we calculated the cogging torque for the shapes of the permanent magnet and the stator pole in an axial permanent magnet generator, and studied the method to minimize the cogging torque. At a first step, several optimum shapes were obtained by using the response surface method. Next, the cogging torques were calculated by using finite element method and finally the optimum design was obtained to minimize the cogging torque of the generator. The analysis model was three phase 1kVA wind power generation having 24 poles and 18 slots. As a result of the optimum design, the cogging torque decreased by 7.37N․m and the EMF increased by 25.63V compared to the basic model.

Load identification of different Halbach-array topologies on permanent magnet synchronous generators using the coupled field-circuit FE methodology

In this paper, the influence of gap consideration on load identification under various Halbach-array-based topologies (HABOs) is investigated while the system is on-duty. The load characteristics of a radial flux generator with closed-slots and the exterior rotor topology is discussed, where the effect of eddy-currents are observed. This comparative study deals with the consideration of the combined moment of inertia calculation that demonstrates how electromagnetic-based post processing calculations are estimated without the aid of nominal machine parameter values. The analysis was performed using a 2-D finite-element simulation of different HABOs with the gap consideration between the segments. Additionally, a comprehensive comparison with no gap is considered. Also, the dynamic analysis using an uncontrolled conventional rectifier model is used to derive effected key output parameters such as torque, output power, power factor, and line-to-line voltage. The major objective of the study is to determine corresponding load results in order to employ the most suitable and capable magnetization topology from the load perspective in the PM synchronous generator (PMSGs). Accordingly, the maximum power (MP) point was carried out to maximize the output DC power. With respect to the combined moment of inertia estimation, the load parameter estimation is verified experimentally on a surface-mounted PMSG using different magnetization topologies. Furthermore, commercial and environmental issues of the project are considered to reduce CO2 emissions as part of green power generation development.

Electromagnetic design of a new axial and radial flux generator with the rotor back-irons

The design and simulation of a new three-phase axial flux generator have been performed. The generator is a permanent magnet machine (PMG) and consists of two rotors at two sides and a stator at the middle. In the machine, each rotor has 16 rare earth disc-type magnets and back-iron units and the stator at the middle has 24 coils. It has been understood that the generator produces directly sinusoidal output and requires no conversion in the wave shape. The 3D simulations have been performed via the finite element analysis (FEA) method by the magnetostatic and magnetodynamic tools. It has been found that the machine generates 3.4 kW at 1000 rpm for the air gap of 1.5 mm. This gives the power density of 336 kW/m3 for the rated value of the generator and it is higher than the power densities of many axial flux generators in the literature. The maximal cogging torque value has been estimated as 3.6 Nm, which is a good value for a back-iron machine. It has been also proven that the waveform harmonics become lower at higher rotor speeds.

Waveform characteristics and losses of a new double sided axial and radial flux generator

In this paper, the waveform characteristics and the losses of a new three phase permanent magnet generator, which has a rated power 250 W at 1000 rpm have been explored theoretically and experimentally. The proposed generator has new flux morphology with the axial and radial directions, therefore the waveform characteristics become important for this new machine. The detailed phase voltage measurements prove that the machine generates sinusoidal waveform and the total harmonic distortion (THD) is found to be sufficient for such a new prototype machine. According to the detailed experimental measurements, the machine has THD values of 0.4% and 4.7% for resistive load and no-load cases. In addition, the losses and the efficiency measurements are found to be very promising although the airgap optimization has not been completed. According to the simulation studies, the machine has the core and copper losses of 2.5 W and 23 W for loaded cases, respectively.

Designing of a Permanent Magnet and Directly Driven Synchronous Generator for Low Speed Turbines

In this study, a radial flux generator which is driven directly for low speed turbines and structured by permanent magnets has been designed and analyzed by finite elements methods. The designed generator model has got the good results which show high performance characteristics of a permanent magnet generator. Both electrical and magnetic parameters of the designed generator have been calculated; the data obtained from the analyses have been commented. Maximum efficiency has been tried to get by interfering to structure of generator regarding to magnetic materials saturation. Comparison results made in the study have been demonstrated that the designed permanent magnet radial flux generator has superior performance rather than normal generator. Ill. 11, bibl. 16, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.112.6.436