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- ELECTRIC MOTORS
- Introduction to rotation
- Magnetic field and magnetic field
- Gravitational density
- Turn on the controller.
- Gravity channels
- Magnetic Force (MMF)
- Electric equation
- Air gap
- Refusal to breathe air
- Indulge
- Magnetic lines in a motor
- Torque output
- Size of fire
- The beauty of snoring
- Special freight and special charges
- unusual loads
- Torque and engine speed
- Specific force output—the importance of speed
- Energy transfer—EMF movements
- lemon engine—static state
- Force interaction involves a leader moving at a constant speed.
- Equivalent circuit
- Condition of the car
- Behavior without a machine load
- behavior and weight of the machine
- The relative magnitude of V and E, as well as their efficiency, are significant.
- Primary engine analysis—results
- General advantages of electric motors
- Heating and cooling usage
- Torque per sound.
- Power per unit—the importance of speed
- Size range: specific lamp and capacity
- Efficiency and speed
- Voltage rating
- The duration extends beyond a brief moment
Preface
Electric motors are so ubiquitous that we hardly think about them. For example, when we turn on an electric drill, we expect it to run quickly up to the correct speed, and we don’t wonder how it knows what speed to run at or why it drops to a very low level once it draws enough energy from the supply to bring it up to speed. The drill consumes more power when we start it, and it automatically reduces its power draw from the mains when we finish, without our intervention. The basic motor, consisting solely of copper coils and steel laminations, demonstrates a sophisticated energy converter that warrants meticulous scrutiny. By understanding how the motor works, we will be able to appreciate its potential and limitations, as well as observe (in later chapters) how the addition of external electronic controllers might improve its already impressive performance.This chapter covers the fundamentals of motor functioning; therefore, readers who are already familiar with topics such as magnetic flux, magnetic and electric circuits, torque, and motional e.m.f. can probably skip a lot of it. Several crucial general ideas and rules come to light during the discussion. Section 1.8 summarizes these general ideas and rules that apply to all motor types. We recommend all readers to internalize these basic principles before tackling other portions of the book, as experience has shown them to be well-equipped to balance the merits and cons of the various motor types.
PRODUCING ROTATION
Almost all motors operate by applying a force to a current-carrying conductor in a magnetic field. The force can be demonstrated by placing a bar magnet near a current-carrying wire (Figure 1.1), but anyone who attempts the experiment will most likely be disappointed to see how weak the force is and will undoubtedly ask how such an unpromising effect can be employed to construct effective motors. We’ll see that a powerful magnetic weld that interacts with as many conductors as possible helps the mechanism work best. Later on, we will understand that the motor requires the magnetic weld, also known as ‘excitation’, to function, but it only acts as a catalyst. The electrical supply to the conductors generates all the mechanical output power. It will become clear later that in some motors, the sections of the machine responsible for excitation and energy conversion are discrete and self-evident. For instance, in a d.c. motor, the fixed component’s clearly defined projecting weld poles provide excitation through permanent magnets or weld coils, while the rotor’s conductors generate force and receive current from sliding brushes. In many motors, however, there is no clear physical boundary between the ‘excitation’ and ‘energy-converting’ components of the machine, and a single fixed winding serves both functions. Nonetheless, we shall see that recognizing and separating the excitation and energy-converting activities is always beneficial in understanding how all types of motors operate.Upon revisiting the subject of force on a single conductor, we will initially examine the factors that dictate the magnitude and orientation of the force, prior to exploring how the mechanism generates rotation. We must delve into the concept of the magnetic circuit, as it plays a crucial role in comprehending the shapes of motors. For those who are unfamiliar with the concepts, a brief overview of magnetic weld, magnetic flux, and flux density is provided first.
Magnetic Field and Magnetic Flux
A magnetic field exerts force on a current-carrying conductor. Experiments reveal that the size of the force is exactly proportional to the current in the wire and the strength of the magnetic field, with the force being greatest when the magnetic field is perpendicular to the conductor.
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