Hi, readers welcome to a new post in this post we will have a detailed look at the Differentially Compounded DC generator. Before going into detail about the thesenerators you must study the CUMULATIVELY COMPOUNDED DC GENERATOR. that we discussed in the previous post. DC generator is a device or machine that is used to transform mechanical power provided by the primer mover in the ac power.
There are many types of dc generators such as shunt dc generators, series dc generators, compound dc generators, etc. In this post, we discuss in detail the differential compound generator its working, operation, and some other related parameters. So let’s get started with a Differentially Compounded DC Generator
Introduction to Differentially Compounded DC Generator
- The differential compound dc generator, comprises of both shunt and series field windings but their configuration is such that their generated flux cancels each that is contrary to the cumulatively compounded generator.
- The equivalent circuitry differentially compounded dc generator can be seen here.
- Note that the armature current direction is away from the dotted point of windings but the shunt field current is moving towards the dotted windings point.
- The equation of MMF for these generators is written here.
Fnet=FF-FSE-FAR
Fnet=NFIF-NSEIA-FAR
- The equivalent shunt field current of series field windings and armature reaction is mentioned here.
Ieq=-NSE/NF x IA-FAR/NF
- The net value of the effective shunt field current is given here.
IF’=IF+Ieq
IF’=IF-NSE/NF x IA-FAR/NF
Terminal Characteristics of a Differentially Compounded DC Generator
- In differential compounded dc generators some factors like the cumulatively compounded generator exist but the difference is that they have similar directions.
- With the increment in armature reaction, IA(RA+RS) losses rise which results in a decrement in the terminal voltage of the generator.
VT=EA-IA(RA+RS)
- With the armature current increment, the MMF series field windings increase FSE=NSEIA. That results in a decrement in the net MMF of generator Ftot=NFIF-NSEIA due to this effect net flux of the generator decreases.
- Flux decrement reduces internally generated voltage that decreases terminal voltage.
- As these 2 factors decrease the terminal voltage with the load increment on the generator.
- The characteristic curve of the differential compound generator diagram, seen here.
Voltage Control of Differentially Compounded DC Generators
- As the voltage loss features of differentially compounded dc generators are worse they can be set the value of terminal voltage for the respective load.
- The method for voltage adjustment of the terminal is similar to the shunt and cumulatively compounded dc generator.
- There are mentions here.
- Vary the speed of rotation of Wm.
- Vary the IF.
Graphical Analysis of Differentially Compounded DC Generator
- The voltage characteristic of the differential compounded dc generator is shown in the graph find accurately in a similar way that we discussed in cumulatively
compounded dc generator. - To measure the terminal characteristics generator show this figure.
- The part of effective shunt field current due to shunt windings is equal to the VT/RF because a high current exists at the shunt field windings.
- The field current remainder is shown by Ieq and is the summation of series windings and armatures reaction.
- This resultant Ieq current denotes the negative horizontal distance across the axes of magnetization curvature as both series field and armature are destructive.
- The resistive losses of the generator is mention by IA(RA+Rs) that is the length about the y-axis at the curve. To measure the value of output voltage for the respective load find an area of the triangle created through resistive voltage losses and equivalent current Ieq and determine the one location where it accurately relies on among the IF line and MMF curve.
Read also:
- Characteristics of Series Wound DC Generator
- Permanent Magnet Synchronous Generator
- What is Electric Generator, Definition, Types, Working Principle, & Applications
- What is the Equivalent Circuit of Synchronous Generator
- Synchronous Generator Ratings
- Introduction to Synchronous Generator, Working, Construction, Types & Applications
Faqs
What is differential compound DC generator?
- It is defined as two types, cumulative compound, and differential compound generators, In differential compound generator series winding restricts the magnetic field generated with shunt winding. It results reduction of generated voltage when load decreases.
What are the different types of DC compound generator?
- DC generators are of 3 types based on field excitation methods. it is a permanent magnet dc generator, a separately excited dc generator, and Self-Excited DC generator.
What are the applications of differential compound DC motor?
- it comes with high starting torque, so ti used for heavy-duty applications like mine hoists, continuous conveyors cranes, electric railways, rolling mills, metallurgical works,
Which are applications of DC compound generators?
- The series dc generator is used in arc lamps for lighting, stable current generator, and a booster. DC generators are used to reimburse voltage losses in feeders. DC generators used to provide power supply for lodges, offices, etc.
What is the difference between cumulative and differential compounded connections?
- First note that there are two fields coils used for dc generator. When fields of both coils support with each other, it is called a cumulative compound and when fields are opposite to each other is called differential compound.
Why differential compound generator is not used in practice?
- The differential compound motor comes with poor torque features so it used in experimental and research work not used for general practices.
What is the principle of DC generator?
- DC generators produce current with the use of Faraday’s law of electromagnetic induction.
- If the conductor is set in a varying magnetic field, EMF force is induced in the conductor. This induced emf is measured through the use of an equation of the electromotive force of a generator.
How can you differentiate the different types of DC generator?
- DC generators are of three types on the bases of field excitation: Permanent Magnet, Separately Excited, and Self-Excited DC generators.
What is the advantage of DC compound motor?
- There are two main benefits of DC motors, speed variation, and torque. Speed variation is done through varying armature voltage or field voltage or a combination of both.
What is a differentially compounded DC generator used for?
- The differential compound wound generator is used for arc welding where high voltage losses and constant current is needed because of larger magnetization armature reaction.
What is the differential compound motor?
- Differentially compound motor comes with shunt field winding and series field winding, but two windings are connected in opposite to each other. When load increases, current in series field winding increases, which causes to decrease the total magnetic flux.
That is a detailed post about the Differentially Compounded DC Generator. If you have any further queries ask in the comments. Thanks for reading. I tried my level best to provide quality knowledge to you. Have a nice day.
