Electric Machines: Types, Operation, and Applications
Change of Polarity
To change the direction of the poles in a generator, you can change the direction of rotation of the generator, change the two poles with two contactors, or permute the rotor. This applies to series, parallel, or loose excitation, with the latter being the best method.
DC Machines
The basic principle of electric power generation involves a magnetic field, movement, and the creation of current. This current is generated when alternating field lines cut through a coil. With two magnets,
Read MoreElectric Machines: Types, Operation, and Applications
Change of Polarity
To change the direction of the poles in a generator, you can change the direction of rotation of the generator, swap the two poles with two contactors, or permute the rotor. This applies to series, parallel, or loose excitation, with the latter being the most effective method.
DC Machines
The basic principle of electric power generation involves a magnetic field, movement, and the creation of current. This current is generated when alternating field lines cut through a coil. With
Read MoreAnalog & Digital Signal Transmission and Data Acquisition Cards
Analog Transmission Signals
This method has two disadvantages:
- The maximum distance is one meter.
- The value of the transmitted signal is not less than 0.1 V.
If these conditions are not met, the voltage drop and interference significantly degrade the signal. This is solved by using a voltage-current converter in the range of 4 to 20 mA, i.e., there are 4 mA to 0V and the maximum voltage is 20 mA. Using the converter is able to increase the transmission distance up to 3 km and also facilitates the detection
Read MoreComponents of a Terrestrial TV Reception System
1. Signal Capture System
These elements receive electromagnetic waves emitted by transmitters and repeaters. They include:
a) Antenna
The antenna transforms electromagnetic energy into electrical energy. A properly installed antenna is crucial for optimal performance. They are typically based on the dipole design, consisting of two conductive rods. Key antenna components include:
- Dipole: Receives electromagnetic waves. Its length corresponds to half the wavelength of the signal.
- Reflector: Reinforces
Understanding DC Motors: Principles, Operation, and Applications
DC Motor
The DC motor is a machine that converts electrical energy into mechanical energy, primarily through rotational movement. While newer applications utilize electric motors for rotary motion, modifications like linear motors produce traction on a rail.
This versatile machine is widely used in various industries. Its easy control over positioning, stopping, and speed makes it a preferred choice for control applications and process automation. However, the rise of electronics and the affordability
Read MoreUnderstanding DC Generators: Principles, Components, and Operation
Understanding DC Generators
1. Operating Principle of a Generator
Electric generators operate based on the interaction between electric current and magnetic fields. When an electric current flows through a wire, it creates a magnetic field around it.
2. Obtaining DC from AC
DC is obtained from AC by using a commutator. The commutator consists of insulated copper segments connected to the armature windings. Brushes, typically made of carbon, make contact with the commutator segments, collecting the generated
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