Characteristics of DC Generator
The primary mover maintains the speed of a DC generator constant. Under such circumstances, the generator’s performance is determined by the relationship between excitation, terminal voltage, and load. These relationships are visually represented as curves known as DC generator characteristics. These characteristics demonstrate the behavior of the DC generator under various load levels.
Open Circuit Characteristics or Magnetization Curve
This graph depicts the relationship between the produced EMF with no load (E0) and the field current (If) at a constant speed. It is also known as no-load saturation curve. Its form is virtually same across a wide range of DC generators, whether independently or self-excited.
Internal Characteristics
The graph depicts the relationship between produced EMF (E) on-load and armature current. Because of the influence of armature response, the magnetic flux on-load is lower than the flux at no-load. As a result, the generated EMF (E) under loaded conditions will be lower than the EMF produced (E0) with no load. As a result, the internal characteristic curves are somewhat lower than the open circuit characteristics.
External properties or load characteristics
The plot of the terminal voltage (V) and load current (IL) represents the external or load characteristics. Because of armature and series field copper losses, the terminal voltage differs from the generated voltage. As a result, the exterior characteristics curve will be lower than the internal characteristics curve by an amount equal to the voltage drop caused by machine copper losses.
Construction And Working of a DC Generator
In 1831, Michael Faraday, a British physicist, devised the electromagnetic generator. The primary function of this device is to convert mechanical energy to electrical energy. There are several types of mechanical energy sources available, including hand cranks, internal combustion engines, water turbines, and gas and steam turbines. The generator provides capacity for all electrical power networks. An electric motor should be able to perform the generator’s converse function. The basic purpose of the motor is to convert electrical energy into mechanical energy. Generators and motors have many properties.
Table of Content
- DC Generator
- Construction of a DC generator
- Workings
- Types
- Losses in DC Machines
- Characteristics of DC Generator
- Characteristics of DC Series Generator
- Characteristics of DC Shunt Generators
- External Load Characteristics of the DC Compound Generator
- Efficiency of a DC Generator