The XIX International Conference on Electrical Machines - ICEM 2010, 2010
ABSTRACT This paper presents variable voltage variable frequency (VVVF) control scheme to tubular... more ABSTRACT This paper presents variable voltage variable frequency (VVVF) control scheme to tubular linear permanent magnet synchronous machine (TLPMSM) with gas springs. To achieve constant drilling speed in the presence of different magnitudes of hardness of rocks, it is necessary to change the input voltage to the machine. Therefore, with change in input voltage, the natural frequency of the spring system changes. In order to maintain the same displacement of the drill bit, the input voltage frequency should also change. The main contribution of this paper is the modeling of the system and analysis of the variation of the natural frequency and a variable voltage variable frequency control method. Simulation results show that VVVF is capable of achieving the desired performance.
2007 IEEE International Electric Machines & Drives Conference, 2007
ABSTRACT This paper mainly describes the force analysis in the design optimization of a reciproca... more ABSTRACT This paper mainly describes the force analysis in the design optimization of a reciprocating linear permanent magnet actuator with interior magnet and slotless stator. This paper predicts the force characteristics according to design parameters such as pole pitch, magnet width and stator inner diameter on the basis of numerical calculations. The design is unique because of the combination of a heavy piston and gas springs. The gas springs allow the piston to oscillate at high frequency and with a long stroke length, in spite of pistons large weight. A large electromagnetic force, due to the use of permanent magnets makes a high power linear electric actuator available. The heavy piston causes a considerable vibration in the housing which is utilized in the drilling application. The load can then be attached directly to the housing and the machine can be made hermitically sealed, which eliminate leakage problems. These features make the actuator suitable as a hammer in oil drilling applications.
2012 XXth International Conference on Electrical Machines, 2012
ABSTRACT The bearingless ac homopolar motor has numerous advantages over classical machines for a... more ABSTRACT The bearingless ac homopolar motor has numerous advantages over classical machines for applications such as flywheel energy storage and as a superconducting machine. In this paper, the bearingless ac homopolar motor is analyzed. Inductance matrices, alignment and reluctance torque calculations, suspension winding configurations, and radial suspension force calculations are presented for two rotor structures. Unlike previous literature, expressions for torque interference caused by suspension force winding configurations and effects of d-axis flux on suspension forces are developed and presented. Furthermore, it is demonstrated that each rotor structure can be analyzed as an equivalent classical machine to allow for easy comparison.
2012 XXth International Conference on Electrical Machines, 2012
ABSTRACT This paper aims to describe the characteristics of the radial magnetic forces in a low-s... more ABSTRACT This paper aims to describe the characteristics of the radial magnetic forces in a low-speed permanent magnet (PM) machine with concentrated windings. Magnetic flux distribution in the airgap is calculated using finite element method and the results are employed to compute the radial forces using Maxwell's stress tensor. The flux density due to PM and MMF magnetic fields and their interaction and also effect of slotting are discussed. Radial forces are investigated in no-load and load conditions. The authors have tried to address the importance of the slot harmonics in the force characteristics. It is shown that the amplitude of the lowest vibration mode is considerable even in no-load, however it increases while the machine is loaded, leading to higher vibration level. The influence of considering the tangential flux density on the force calculation is also investigated. It is found that in the case of neglecting tangential flux component, the level of calculated radial magnetic forces decreases considerably.
The XIX International Conference on Electrical Machines - ICEM 2010, 2010
This paper presents how to analytically design a high-torque three-phase flux-switching permanent... more This paper presents how to analytically design a high-torque three-phase flux-switching permanent magnet machine with 12 stator poles and 14 rotor poles. Firstly, the machine design parameters are studied addressing on high output torque and its flux distribution is also investigated by finite-element method (FEM) analysis. Then a simplified lumped parameter magnetic circuit model is built up for analyzing design
The XIX International Conference on Electrical Machines - ICEM 2010, 2010
This paper investigates a newly designed flux-switching permanent magnet machine with 12 stator p... more This paper investigates a newly designed flux-switching permanent magnet machine with 12 stator poles and 14 rotor poles for downhole application where the ambient temperature is around 150°C. This machine having an outer diameter of 100 mm and an active axial length of 200 mm can provide ~2.7 kW with an output torque up to 25 Nm, an efficiency of
2012 XXth International Conference on Electrical Machines, 2012
ABSTRACT This paper presents the research on direct-driven ironless permanent magnet generator wi... more ABSTRACT This paper presents the research on direct-driven ironless permanent magnet generator with a diameter over 24 m that can be used in offshore wind power plants. Machines with ironless stator do not suffer from attraction forces between the rotor and the stator so a very low total weight can be achieved even with the large-diameter carrying structure. By using modularized active parts, manufacturing, transportation, assembly and repair of the large-diameter generator becomes possible. Several variants of turbine design and the corresponding ways to integrate the generator into the turbine are discussed. Several axial-flux and radial-flux machine variants are modeled with the help of the finite element method. Comparison of the different generators is carried out based on such criteria as active mass, material cost and efficiency.
2009 35th Annual Conference of IEEE Industrial Electronics, 2009
ABSTRACT Tubular linear permanent magnet machine with gas springs using for drilling applications... more ABSTRACT Tubular linear permanent magnet machine with gas springs using for drilling applications is presented. This machine has the advantage of directly transmitting electric power to rock without gears. In this paper, mathematical model with hammering effect is established and dynamic process of oscillatory motion is analyzed. Simulation results show that this machine is suitable for drilling application.
2008 18th International Conference on Electrical Machines, 2008
ABSTRACT This paper describes the design and modeling of demonstration model of a linear permanen... more ABSTRACT This paper describes the design and modeling of demonstration model of a linear permanent magnet actuator. This demonstration model used to verify the idea of using gas springs with linear permanent magnet actuator to produce strong vibrations for drilling applications.
Tubular linear permanent magnet motor with gas springs using for drilling applications is present... more Tubular linear permanent magnet motor with gas springs using for drilling applications is presented in this paper. This motor has the advantage of directly transmitting electric power to rock without gears. Mathematical model with hammering effect is established and dynamic process of oscillatory motion is analyzed. Dynamic response comparison of no load mode and load mode is done. Simulation results show that this motor is suitable for drilling application.
The XIX International Conference on Electrical Machines - ICEM 2010, 2010
ABSTRACT This paper presents variable voltage variable frequency (VVVF) control scheme to tubular... more ABSTRACT This paper presents variable voltage variable frequency (VVVF) control scheme to tubular linear permanent magnet synchronous machine (TLPMSM) with gas springs. To achieve constant drilling speed in the presence of different magnitudes of hardness of rocks, it is necessary to change the input voltage to the machine. Therefore, with change in input voltage, the natural frequency of the spring system changes. In order to maintain the same displacement of the drill bit, the input voltage frequency should also change. The main contribution of this paper is the modeling of the system and analysis of the variation of the natural frequency and a variable voltage variable frequency control method. Simulation results show that VVVF is capable of achieving the desired performance.
2007 IEEE International Electric Machines & Drives Conference, 2007
ABSTRACT This paper mainly describes the force analysis in the design optimization of a reciproca... more ABSTRACT This paper mainly describes the force analysis in the design optimization of a reciprocating linear permanent magnet actuator with interior magnet and slotless stator. This paper predicts the force characteristics according to design parameters such as pole pitch, magnet width and stator inner diameter on the basis of numerical calculations. The design is unique because of the combination of a heavy piston and gas springs. The gas springs allow the piston to oscillate at high frequency and with a long stroke length, in spite of pistons large weight. A large electromagnetic force, due to the use of permanent magnets makes a high power linear electric actuator available. The heavy piston causes a considerable vibration in the housing which is utilized in the drilling application. The load can then be attached directly to the housing and the machine can be made hermitically sealed, which eliminate leakage problems. These features make the actuator suitable as a hammer in oil drilling applications.
2012 XXth International Conference on Electrical Machines, 2012
ABSTRACT The bearingless ac homopolar motor has numerous advantages over classical machines for a... more ABSTRACT The bearingless ac homopolar motor has numerous advantages over classical machines for applications such as flywheel energy storage and as a superconducting machine. In this paper, the bearingless ac homopolar motor is analyzed. Inductance matrices, alignment and reluctance torque calculations, suspension winding configurations, and radial suspension force calculations are presented for two rotor structures. Unlike previous literature, expressions for torque interference caused by suspension force winding configurations and effects of d-axis flux on suspension forces are developed and presented. Furthermore, it is demonstrated that each rotor structure can be analyzed as an equivalent classical machine to allow for easy comparison.
2012 XXth International Conference on Electrical Machines, 2012
ABSTRACT This paper aims to describe the characteristics of the radial magnetic forces in a low-s... more ABSTRACT This paper aims to describe the characteristics of the radial magnetic forces in a low-speed permanent magnet (PM) machine with concentrated windings. Magnetic flux distribution in the airgap is calculated using finite element method and the results are employed to compute the radial forces using Maxwell's stress tensor. The flux density due to PM and MMF magnetic fields and their interaction and also effect of slotting are discussed. Radial forces are investigated in no-load and load conditions. The authors have tried to address the importance of the slot harmonics in the force characteristics. It is shown that the amplitude of the lowest vibration mode is considerable even in no-load, however it increases while the machine is loaded, leading to higher vibration level. The influence of considering the tangential flux density on the force calculation is also investigated. It is found that in the case of neglecting tangential flux component, the level of calculated radial magnetic forces decreases considerably.
The XIX International Conference on Electrical Machines - ICEM 2010, 2010
This paper presents how to analytically design a high-torque three-phase flux-switching permanent... more This paper presents how to analytically design a high-torque three-phase flux-switching permanent magnet machine with 12 stator poles and 14 rotor poles. Firstly, the machine design parameters are studied addressing on high output torque and its flux distribution is also investigated by finite-element method (FEM) analysis. Then a simplified lumped parameter magnetic circuit model is built up for analyzing design
The XIX International Conference on Electrical Machines - ICEM 2010, 2010
This paper investigates a newly designed flux-switching permanent magnet machine with 12 stator p... more This paper investigates a newly designed flux-switching permanent magnet machine with 12 stator poles and 14 rotor poles for downhole application where the ambient temperature is around 150°C. This machine having an outer diameter of 100 mm and an active axial length of 200 mm can provide ~2.7 kW with an output torque up to 25 Nm, an efficiency of
2012 XXth International Conference on Electrical Machines, 2012
ABSTRACT This paper presents the research on direct-driven ironless permanent magnet generator wi... more ABSTRACT This paper presents the research on direct-driven ironless permanent magnet generator with a diameter over 24 m that can be used in offshore wind power plants. Machines with ironless stator do not suffer from attraction forces between the rotor and the stator so a very low total weight can be achieved even with the large-diameter carrying structure. By using modularized active parts, manufacturing, transportation, assembly and repair of the large-diameter generator becomes possible. Several variants of turbine design and the corresponding ways to integrate the generator into the turbine are discussed. Several axial-flux and radial-flux machine variants are modeled with the help of the finite element method. Comparison of the different generators is carried out based on such criteria as active mass, material cost and efficiency.
2009 35th Annual Conference of IEEE Industrial Electronics, 2009
ABSTRACT Tubular linear permanent magnet machine with gas springs using for drilling applications... more ABSTRACT Tubular linear permanent magnet machine with gas springs using for drilling applications is presented. This machine has the advantage of directly transmitting electric power to rock without gears. In this paper, mathematical model with hammering effect is established and dynamic process of oscillatory motion is analyzed. Simulation results show that this machine is suitable for drilling application.
2008 18th International Conference on Electrical Machines, 2008
ABSTRACT This paper describes the design and modeling of demonstration model of a linear permanen... more ABSTRACT This paper describes the design and modeling of demonstration model of a linear permanent magnet actuator. This demonstration model used to verify the idea of using gas springs with linear permanent magnet actuator to produce strong vibrations for drilling applications.
Tubular linear permanent magnet motor with gas springs using for drilling applications is present... more Tubular linear permanent magnet motor with gas springs using for drilling applications is presented in this paper. This motor has the advantage of directly transmitting electric power to rock without gears. Mathematical model with hammering effect is established and dynamic process of oscillatory motion is analyzed. Dynamic response comparison of no load mode and load mode is done. Simulation results show that this motor is suitable for drilling application.
Uploads