30-04-2011, 03:25 PM
Presented By :-
Amiya Ranjan
[attachment=13150]
CONTACTLESS ENERGY TRANSFER TO A MOVING ACTUATOR
What is an Actuator ?
An actuator is a mechanical device for moving or controlling a mechanism or system. It is operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or pneumatic pressure, and converts that energy into some kind of motion.
Mechanical actuators operate by conversion of rotary motion into linear motion, or vice versa.
Contd….
Actuators can create a linear motion, rotary motion, or oscillatory motion. That is, they can create motion in one direction, in a circular motion, or in opposite directions at regular intervals.
Many actuators have more than one type of power source. Solenoid valves, for example, can be powered by air and electricity.
Types of Actuators
Hydraulic Actuator
Piston Actuator
Brake Actuator
Mechanical Actuator
Cylindrical Actuator
Steady-State Electric Circuit Analysis
The electric circuit of the CET system is shown in this fig, where V1 is the RMS voltage of the power supply, I1 the RMS current supplied by the power supply, I2 the RMS current induced in the secondary circuit.
C1 & C2 are the series resonant capacitor in the circuit.
L1 & L2 are the self inductance of the coil’s
Contd….
Contactless Energy Transfer Topology
The design of the primary and secondary coil is optimized to get a coupling that is as constant as possible for a sufficiently large area. This area should be large enough to allow the secondary coil to move from one primary coil to the next one without a large reduction in coupling. If this can be achieved, the power can be transferred by one primary coil that is closest to the secondary coil.
To ensure a smooth energy transfer to the moving load, the position dependence of the coupling should be minimized, while keeping the coupling high enough to get a high-efficiency energy transfer.
Dimension of Primary & secondary Coil
Primary & Secondary Coil
Secondary Coil Above a Matrix Of Nine Primary coils
The drawing in above fig. shows one secondary coil above nine primary coils. The black square shows the area in which the center of the secondary coil can move while maintaining good coupling with the middle primary coil. The secondary coil is situated in the bottom-left corner of the area of interaction with the middle primary coil.
Coupling Between Primary & secondary Coil
The coupling between the primary coil and the secondary coil within that area is calculated with Maxwell 3D 10 Opti-metrics and measured. The results are shown in Fig. 4, which show that the FEM predictions are very close to the measured values.
Experimental Setup Of Contactless Energy Transfer
The secondary coil is fixed onto a ceramic plate that is bolted to the mover of a linear actuator. Again ceramic material is used for heat conduction and the minimization of eddy current losses. The linear actuator can move the secondary coil over the three primary coils. The position of the secondary coil with respect to the array of primary coils is measured by the encoder of the linear actuator. A picture of the experimental setup is shown in above Fig.
CD Electrical Drive & Rectifier Connected to Secondary Coil
The secondary coil is connected in series with a resonant capacitor. The circuit is then connected to a full-bridge diode rectifier to generate a DC output. The DC output of the rectifier is connected to the load, which is an electromotor of a CD drive running at 12 VDC as shown in above Fig.
All subsystems are connected to a ds1103 dSpace system running the control program at 8 kHz.
Result…
Contd….
Fig. Shows Graphs Of Measured voltage , current & active Primary coil for CD Drive
Description About Graphs
An electromotor of a CD drive that runs on 12 VD is connected to the rectifier. The voltage and current from the DC bus supply as well as the voltage and current to the CD drive are measured and shown in Fig. 10 and 11. The secondary coil is moving over all three primary coils
The frequency of the sinusoidal position reference is 2 Hz, so in one second the secondary coil makes two cycles (one cycle implies moving from primary coil 1 over primary coil 2 to primary coil 3 and back).
Value Of Voltages, Current & Efficiency Of CET to a CD Drive Electro-motor
Conclusion
A new topology for contactless energy transfer (CET) to a Actuator has been proposed, built and tested.
The CET topology allows for a long-stroke movement in a plane and a short-stroke movement of a few millimeters perpendicular to the plane.
In addition, it is tolerant to small rotations. The power electronics consist of a half-bridge square wave power supply for each primary coil and series resonant capacitor and a full-bridge diode rectifier at the load.
Amiya Ranjan
[attachment=13150]
CONTACTLESS ENERGY TRANSFER TO A MOVING ACTUATOR
What is an Actuator ?
An actuator is a mechanical device for moving or controlling a mechanism or system. It is operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or pneumatic pressure, and converts that energy into some kind of motion.
Mechanical actuators operate by conversion of rotary motion into linear motion, or vice versa.
Contd….
Actuators can create a linear motion, rotary motion, or oscillatory motion. That is, they can create motion in one direction, in a circular motion, or in opposite directions at regular intervals.
Many actuators have more than one type of power source. Solenoid valves, for example, can be powered by air and electricity.
Types of Actuators
Hydraulic Actuator
Piston Actuator
Brake Actuator
Mechanical Actuator
Cylindrical Actuator
Steady-State Electric Circuit Analysis
The electric circuit of the CET system is shown in this fig, where V1 is the RMS voltage of the power supply, I1 the RMS current supplied by the power supply, I2 the RMS current induced in the secondary circuit.
C1 & C2 are the series resonant capacitor in the circuit.
L1 & L2 are the self inductance of the coil’s
Contd….
Contactless Energy Transfer Topology
The design of the primary and secondary coil is optimized to get a coupling that is as constant as possible for a sufficiently large area. This area should be large enough to allow the secondary coil to move from one primary coil to the next one without a large reduction in coupling. If this can be achieved, the power can be transferred by one primary coil that is closest to the secondary coil.
To ensure a smooth energy transfer to the moving load, the position dependence of the coupling should be minimized, while keeping the coupling high enough to get a high-efficiency energy transfer.
Dimension of Primary & secondary Coil
Primary & Secondary Coil
Secondary Coil Above a Matrix Of Nine Primary coils
The drawing in above fig. shows one secondary coil above nine primary coils. The black square shows the area in which the center of the secondary coil can move while maintaining good coupling with the middle primary coil. The secondary coil is situated in the bottom-left corner of the area of interaction with the middle primary coil.
Coupling Between Primary & secondary Coil
The coupling between the primary coil and the secondary coil within that area is calculated with Maxwell 3D 10 Opti-metrics and measured. The results are shown in Fig. 4, which show that the FEM predictions are very close to the measured values.
Experimental Setup Of Contactless Energy Transfer
The secondary coil is fixed onto a ceramic plate that is bolted to the mover of a linear actuator. Again ceramic material is used for heat conduction and the minimization of eddy current losses. The linear actuator can move the secondary coil over the three primary coils. The position of the secondary coil with respect to the array of primary coils is measured by the encoder of the linear actuator. A picture of the experimental setup is shown in above Fig.
CD Electrical Drive & Rectifier Connected to Secondary Coil
The secondary coil is connected in series with a resonant capacitor. The circuit is then connected to a full-bridge diode rectifier to generate a DC output. The DC output of the rectifier is connected to the load, which is an electromotor of a CD drive running at 12 VDC as shown in above Fig.
All subsystems are connected to a ds1103 dSpace system running the control program at 8 kHz.
Result…
Contd….
Fig. Shows Graphs Of Measured voltage , current & active Primary coil for CD Drive
Description About Graphs
An electromotor of a CD drive that runs on 12 VD is connected to the rectifier. The voltage and current from the DC bus supply as well as the voltage and current to the CD drive are measured and shown in Fig. 10 and 11. The secondary coil is moving over all three primary coils
The frequency of the sinusoidal position reference is 2 Hz, so in one second the secondary coil makes two cycles (one cycle implies moving from primary coil 1 over primary coil 2 to primary coil 3 and back).
Value Of Voltages, Current & Efficiency Of CET to a CD Drive Electro-motor
Conclusion
A new topology for contactless energy transfer (CET) to a Actuator has been proposed, built and tested.
The CET topology allows for a long-stroke movement in a plane and a short-stroke movement of a few millimeters perpendicular to the plane.
In addition, it is tolerant to small rotations. The power electronics consist of a half-bridge square wave power supply for each primary coil and series resonant capacitor and a full-bridge diode rectifier at the load.
