Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

DC Generator DefinitionA DC generator is a device that converts mechanical energy into direct current electricity for various applications.Application of Separately Excited DC Generators These type of DC generators are generally more expensive than self-excited DC generators, because they need a separate excitation source. This restricts their applications. They are used where self-excited generators do not perform well. Because of their ability of giving wide range of voltage output, they are g

Shunt Wound DC Generator DefinitionIn shunt wound DC generators, the field windings are connected in parallel with the armature conductors. In these types of generators the armature current (Ia) splits into two parts: the shunt field current (Ish) flows through the shunt field winding, and the load current (IL) flows through the external load.Three most important characteristic of shunt wound DC generators are discussed below:Magnetic CharacteristicThe magnetic characteristic curve shows the rel

DC Generator Types Permanent Magnet DC Generators – Field coils excited by permanent magnets Separately Excited DC Generators – Field coils excited by some external source Self Excited DC Generators – Field coils excited by the generator itselfSelf Excited GeneratorA self-excited DC generator uses its own output to power its field coils, which can be arranged as series, shunt, or compound wound.The three types of self-excited DC generators are: Series Wound Generators Shunt Wound Generators Comp

Series Generator DefinitionA series wound DC generator is defined as a generator where the field windings, armature windings, and external load circuit are connected in series, causing the same current to flow through each part.In these types of generators the field windings, armature windings and external load circuit all are connected in series as shown in figure below.Therefore, the same current flows through armature winding, field winding and the load.Let, I = Ia = Isc = ILHere, Ia = armatu

Definition of Separately Excited DC GeneratorA separately excited DC generator is defined as a DC generator where the field winding is powered by an external source.Magnetic or Open Circuit CharacteristicThe curve which gives the relation between field current (If) and the generated voltage (E0) in the armature on no load is called magnetic or open circuit characteristic of a DC generator. The plot of this curve is practically same for all types of generators, whether they are separately excited

How dose a DC Generator Work?DC Generator DefinitionA DC generator is a device that converts mechanical power into direct electrical power using the principle of electromagnetic induction.Faraday’s LawThis law states that when a conductor moves in a magnetic field it cuts magnetic lines of force, which induces an electromagnetic force (EMF) in the conductor.The magnitude of the induced EMF depends on the rate of change of the magnetic flux linkage with the conductor. This EMF will cause a curren

Performance Curves DefinitionPerformance curves of a DC generator are graphs that show how the output voltage changes as the load current varies from no load to full load. These are also known as characteristic curves. These curves help us understand the voltage regulation of different types of DC generators. Better performance is indicated by lower voltage regulation.Separately Excited DC GeneratorThough this type of DC generators are rarely used due to its cost for the separate excitation but

What are Self Excited DC Generators?Self-excited DC generatorA modern DC generator with an exciting coil is a self-excited generator, which starts with the initial current in the exciting coil. When the generator is turned off, a small magnetic force is generated in the rotor iron, which induces an electromotive force in the armature and therefore generates a current in the field windings. Initially, the weak magnetic field produces a small current in the coil, but in order to maintain self-exci

What is the EMF Equation of DC Generator?EMF definitionElectromotive force (EMF) in a DC generator is defined as the voltage generated by the movement of a conductor through a magnetic field.Faraday's lawThis law explains that the induced electromotive force in a generator conductor is proportional to the rate at which it crosses the magnetic field line.Generator groupA DC generator consists of a conductor, a magnetic field, an armature, a magnetic pole, and a winding path, which together affect

What is the Parallel Operation of DC Generators?Parallel operation definition of DC generatorIn modern power systems, power is usually provided by many parallel synchronous generators to ensure continuous operation of the plant. The use of single large generators is now obsolete. Having two generators in parallel helps keep them in sync. Adjusting their armature currents and properly connecting them to the bus bars can solve any synchronization problems.Busbar connectionGenerators in power plant