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

Induction Generator DefinitionAn induction generator (also known as an asynchronous generator) is defined as an induction machine used to generate electricity.Operating PrincipleInduction generators work when the slip is negative, achieved by increasing the prime mover speed beyond synchronous speed.Magnetizing Current RequirementThey require external sources for magnetizing current and reactive power, often provided by supply mains or other generators.Self-Excited GeneratorsThis type, also know

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

Wave Winding: Simplex, Duplex, Retrogressive And Progressive Wave WindingsKey learnings:Wave Winding Definition: A wave winding is defined as a type of armature winding where the end of one coil connects to the start of another, creating a wave-like pattern.Simplex Wave Winding: Simplex wave winding has odd back pitch and front pitch that are nearly equal and suitable for high voltage, low current machines.Duplex Wave Winding: Duplex wave winding involves two parallel paths and is used for highe

Frog Leg Winding DefinitionA frog leg winding is a combination of a multiplex wave and a simplex lap winding in the same slots. It retains the advantages of both lap windings and wave windings without their inherent disadvantages.Lap and wave windings each have an equal number of parallel paths, which are connected to the same commutator.The frog-leg winding has as many parallel paths as duplex lap windings because the simplex lap winding portion supplies ‘P’ number of parallel paths and the mul

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

Magnetization Curve of DC GeneratorKey learnings: Magnetization Curve Definition: The magnetization curve of a DC machine shows the relationship between field current and armature terminal voltage on an open circuit. Importance: The magnetization curve indicates the saturation of the magnetic circuit, crucial for understanding the generator’s efficiency. Saturation Point: This point, also known as the knee of the curve, shows where further increases in field current yield minimal increases in fl

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

What is Lap Winding ?Lap Winding DefinitionLap Winding Definition: A lap winding is defined as a winding where successive coils overlap and connect to the same commutator segment under the same magnetic pole.Simplex Lap Winding: In Simplex Lap Winding, the number of parallel paths between the brushes equals the number of poles.Duplex Lap Winding: In Duplex Lap Winding, the number of parallel paths between the brushes is twice the number of poles.Lap Winding Formula: Important formulae include Ba