Optimization of Pole Numbers and Rotor Size for a Single Phase Slot-Less Permanent Magnet Generator.

This paper discussed on the optimization of a permanent magnet generator (PMG). Generally, the PMG is a slot-less type topology, operated in a single-phase, and it was developed to energize the linear motor in pruner application. Due to this application, a compact generator that can produce up to 100W output power is required since the overall size of the PMG is important. Permeance Analysis Method (PAM) is used to analyzed the PMG performance characteristic. Finite Element Method (FEM) and measurement of the PMG prototype were used to verify the PAM result. Various numbers of poles and rotor size were considered during this analysis. The results show that the slot-less PMG with stator size of 104 mm will produce maximum power of 110 W when it has 6-poles with rotor radius is 37 mm. Based on the results, the calculation method using PAM shows good agreement with measurement and FEM simulation

DDPWM-based power conversion system using three to four phase matrix converter for stand-alone power system

This paper presents a novel stand-alone power system using a three to four phase matrix converter (MC) for use with renewable energy sources such as a micro hydro turbine or a tiny wind turbine with a permanent magnet synchronous generator (PMSG). MCs are able to convert AC power to AC power directly without using DC link capacitors, and AC to DC conversion is also possible because DC is considered to be a type of AC power. Here, two single phase AC outputs with constant frequency and two DC outputs for a battery storage system are described for a fluctuating voltage source. Direct duty ratio pulse width modulation (DDPWM) is used to achieve the desired output because it is easy to expand an ordinary three to three phase MC to produce a three to four phase MC. In addition, fictitious reference iterative tuning (FRIT) is used to design the controller gains. The validity of the proposed method is demonstrated using MATLAB/Simulink simulations

Linear oscillatory actuator integrated with magnetic gear for E-cutter development

This paper proposes a linear oscillatory actuator integrated with a magnetic gear for E-cutter development to harvest oil palm fresh fruit bunch (FFB). The machine comprises of a linear magnetic gear which is artfully integrated with a slotless linear motor. The idea is proposed to improve the performance of existing linear actuators. The design is targeted for a optimum motor thrust, light weight, low cycle time, and reliable displacement. Most importantly, the direction of motion for both the linear motor and linear magnetic gear is opposite to each other, and this could reduce the vibration disturbance from the machine. The performance of the proposed machine is analyzed by finite element method (FEM) and the simulation results verify the machine design

Design and development of a slot-less permanent magnet linear motor using permeance analysis method for spray application

Mostly in industrial spray applications pneumatic systems are utilized for operating the automatic spray gun. Linear motor can be one of the alternatives for triggering the spray gun instead of pneumatic systems due to its accuracy in valve positioning according to the required flow rate. From this point of view a tubular linear permanent magnet motor has been designed using Permeance Analysis Method (PAM) and developed. Three permeance models have been developed for PAM analysis. Among these three models, only one model is selected as a PAM model which can be produced the required amount of thrust for triggering the spray gun. After selecting the PAM thrust model, the size of the motor has been optimized by analyzing the effect of thrust constant, electrical and mechanical time constant. Finally based on the optimized data, the motor has been fabricated and tested that shows the good argument with the analysis result

Metal shape detection and evaluation using giant magneto resistance system

Visual inspection to locate metals embedded in walls or floors is impractical. Detection of these metals can only be done with a proper metal detection. Accordingly, the development of a magnetic imaging system based on giant magneto-resistance (GMR) sensors is presented for metal shape detection. This system is based on magnetic flux leakage testing (MFLT) principle for detecting the shape of ferromagnetic material specimens. The imaging system is constructed using 21 linear GMR sensors array as signals sensing unit (SSU). In this study, a few ferromagnetic SS400 mild steels specimens in various shapes are used as specimens. Image produced confirm system functionality in detecting and evaluating metal shapes

Double side interior permanent magnet linear synchronous motor and drive system

Linear motor has been applied in various fields such as factory and office automation. A linear motor differs from a rotational motor, in which it has a simpler structure. Linear Synchronous Motor is one of the types of linear motor and its application is very wide which is from the small application (i.e. industrials automation) to large application (i.e. maglev transportation) [1]. The thrust which is generated by linear motor is high, even with the size of the motor is small [2]. This is the feature of the linear motor compared to rotational motor where a gear is needed to change the rotational movement to the linear movement. Therefore the linear motor can reduce the mechanical losses. This paper discuss on the proposal of Double Side Interior Permanent Magnet of Linear Synchronous Motor (DIPM-LSM). The structure and three dimensions of magnetic circuit of DIPM-LSM are discussed. This type of DIPM-LSM can be driven by sinusoidal and pulse voltage input. The three phase two coils excitation-driving mode of open loop drive systems are also been discussed

A survey of broken rotor bar detection using PT and HT in squirrel cage electrical machine

Early detection of faults in electrical machines are imperative because of their diversity of use in different fields. A suitable fault monitoring scheme helps to stop propagation of the failure or limit its escalation to severe degrees and thus prevents unscheduled downtimes that cause loss of production and financial income. In this study, a survey of methods based on the Park transform and Hilbert transform for broken rotor bar fault monitoring in Squirrel cage electrical machine is presented

Design Process Involved in Developing Mechanism of linear Motor Operated Multiple Spray Operations Spray Gun.

Normally spray operation has been carried out in various processes such as air spray, High volume low pressure spray, air less spray, air assisted air less spray, electrostatic spray, ultrasonic spray etc. To carry out the spray operation in different processes different types of spray guns are used. Sometimes different types of spray operations are needed to finish the task of a certain product. In that case two or more types of spray guns are use to fulfill the requirement which is costly. On the other hand in automatic spray application, pneumatic system is used to trigger the spray gun. But the main disadvantage of pneumatic system is to position the fluid flow control valve as desired. This system needs more control knobs and highly skilled operator to carry out the quality spray operation. By addressing this issue a spray gun is designed in such a way that it can be accumulated four types of spay processes such as air spray, High volume low pressure air spray, air less spray and air assisted air less spray and the triggering operation has been carried out by specially designed sensor less DC linear motor. CATIA software is used to design the total spray gun model. In the first phase all the component of the spray gun such as spray unit, spray unit holder and shaft assembly, air control unit, triggering lever, motor housing, motor, and cover plate have been designed and then assemble all components to get the total spray gun model in the second phase accordingly. This paper is focused on to discuss the complete design processes involved in developing this especially dedicated spray gun and its operating mechanism

Evaluation of a dual-purpose chemical applicator for paddy fields

A dual-purpose chemical applicator for flooded paddy field was developed to boost agricultural mechanization in rice production and also to overcome the safety concern of hazardous spray drift during chemical application by the paddy farmers. The dual purpose applicator was mounted on a high clearance tractor and could also be used with remote-controlled buoyant vehicle which was propelled by electric motors within the flooded paddy field. The machine performances for both granular and liquid chemical application were reported. Results from the experimental tests suggest that the average effective field capacity for the equipment with a prime mover was found to be 0.89 ha/hr or 7.12 ha/man-day for a 8 hour working day

Effects of wing size on magnetic levitation using coil induced field

The paper discusses the effect of wing size on magnetic levitation using coil induced field for a proposed Levitator Guide (LG). The levitation consists of two main parts namely permanent magnet and current carrying copper coils. The variation of these parts may effects the produced levitated force. A few models have been analyzed with simulation. Results indicated that levitator guide model of wings with centered elbow give rise to the desired performance. Finally, a new type of levitator guide is proposed and fabricated