Rotational Linear Velocity Acceleration Motion Angular Velocity Angular

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Rotational • Linear Velocity • Acceleration Motion . Angular Velocity . Angular

Rotational • Linear Velocity • Acceleration Motion . Angular Velocity . Angular

Newton’s Law of Rotation (force applied) (perpendicular distance) (Fig 1 -2. ) (J: moment

Newton’s Law of Rotation (force applied) (perpendicular distance) (Fig 1 -2. ) (J: moment of Inertia. )

Magnetic Field 磁場 安培定律是說明電流產生磁場的基本定律。 • Ampere’s Law I • Magnetic Field Intensity H

Magnetic Field 磁場 安培定律是說明電流產生磁場的基本定律。 • Ampere’s Law I • Magnetic Field Intensity H

Magnetic Flex Φ, B • Magnetic Flex Φ • Magnetic Flex Density B

Magnetic Flex Φ, B • Magnetic Flex Φ • Magnetic Flex Density B

EX 1 -2 given : B, N, R find: R, Ф, I

EX 1 -2 given : B, N, R find: R, Ф, I

EX 1 -3 given : N, I, R find: R, Ф

EX 1 -3 given : N, I, R find: R, Ф

1. 6 Induced Force on a wire Motor action I

1. 6 Induced Force on a wire Motor action I

1. 7 Induced Voltage + _

1. 7 Induced Voltage + _

1. 8 the Linear DC Machine Fig 1 -19.

1. 8 the Linear DC Machine Fig 1 -19.

Starting the DC Machine

Starting the DC Machine

Linear DC Machine Behaves: 1. At Start: 2. Force: 3. Accelerate: 4. Reduce I

Linear DC Machine Behaves: 1. At Start: 2. Force: 3. Accelerate: 4. Reduce I : 5. Decrease F: 6. At F=0; 7. Move at a constant speed

Linear DC Machine as a Motor: is applied to the bar: 1. 2. 3.

Linear DC Machine as a Motor: is applied to the bar: 1. 2. 3. 4. 5. Bar begins to slow down, Induced voltage drops Decrease current: Increase Until; Fig 1 -23

Linear DC Machine as a Generator 1. Applied force (right) , 2. Increase Velocity

Linear DC Machine as a Generator 1. Applied force (right) , 2. Increase Velocity v 3. Induced Voltage 4. With 5. Current 6. Induced force 7. 8. , (Battery is charging)

http: //www. mpoweruk. com/machines. htm

http: //www. mpoweruk. com/machines. htm

DC Machine

DC Machine

DC Machinery Fundamentals

DC Machinery Fundamentals

DC Gen

DC Gen

DC & AC Gen

DC & AC Gen

DC Generator

DC Generator

The Induce Torque

The Induce Torque

Structure

Structure

Ex 8 -1 Give: a. Switch closed Steady state:

Ex 8 -1 Give: a. Switch closed Steady state:

b. Starting condition Noload steady-state condition

b. Starting condition Noload steady-state condition

C. load torque is applied ; 1. Speed decrease: …………………. 2. Rotor current: ……………

C. load torque is applied ; 1. Speed decrease: …………………. 2. Rotor current: …………… 3. 4. until:

Power supplied to the shaft: Power out of battery:

Power supplied to the shaft: Power out of battery:

d. A Torque Is Applied in Direction of Motion , a. The rotor accelerates

d. A Torque Is Applied in Direction of Motion , a. The rotor accelerates ; Speed increase

D b. c. d. (charge)

D b. c. d. (charge)

DC machine basics(換相 ) X X Force South pole X Angular velocity X Zero

DC machine basics(換相 ) X X Force South pole X Angular velocity X Zero Force North pole

換相 Commutation

換相 Commutation

Basic theory

Basic theory

8. 2 Commutation (2 P) 折疊 波繞

8. 2 Commutation (2 P) 折疊 波繞

Lap-wound A lap winding is m-plax; Pitch: Current path: 折疊

Lap-wound A lap winding is m-plax; Pitch: Current path: 折疊

Lap-Wound

Lap-Wound

The Wave Winding Pitch: Multiplex wave C is the number of coil on the

The Wave Winding Pitch: Multiplex wave C is the number of coil on the rotor. Current path:

8. 4 Problems With Commutation Armature Reaction Neutral-plane shift a. Arcing and sparking b.

8. 4 Problems With Commutation Armature Reaction Neutral-plane shift a. Arcing and sparking b. Total average flux is decrease flux weakening. (8 -24 8 -25) Voltage will be induced in the …. commutation segment.

Armature Reaction

Armature Reaction

Solutions to the Problems With Commutation Three approaches have been developed to correct the

Solutions to the Problems With Commutation Three approaches have been developed to correct the problems of armature reaction and voltage. 1. Brush shift(depend on load; G; M 2. Commutating poles or interpoles 3. Compensating winding )

Basic theory

Basic theory

Ex 3. 3

Ex 3. 3

Ex 3. 4

Ex 3. 4

Ex 3. 4 b

Ex 3. 4 b

Ex 3. 4 c

Ex 3. 4 c

效率 與 損失 1. Copper Losses: 2. Core losses a. hysteresis loss b. eddy

效率 與 損失 1. Copper Losses: 2. Core losses a. hysteresis loss b. eddy current loss 3. Mechanical Losses 4. Stray Losses (Miscellaneous Losses )

效率 (motor)

效率 (motor)

Losses Generator Motor

Losses Generator Motor

Voltage Regulation

Voltage Regulation