Working of Generators Explained

3D Animation Tech

Working of Generators Explained with 3D Animation #Generators #Generator

Transcript

00:00Are you curious about how generators work?

00:02Let's delve into the fascinating world of generators and uncover the simplicity behind their operation.

00:07Although generators and motors have similar structures, their functions are completely different.

00:12One converts mechanical energy into electrical energy,

00:16and the other converts electrical energy into mechanical energy.

00:19First, you must know that when the total magnetic flux passing through the conducting coil changes,

00:25induced electromotive force will be generated in the conductor,

00:29which can be simply understood as voltage generating an induced current in the conductor coil.

00:34This phenomenon was first discovered by Faraday.

00:37In order to understand it better, let's take a look at this simple model of a generator.

00:42The metal coil in front of it is called a power transmission.

00:45It generates electricity by rotating between two magnets to provide mechanical power for the power transmission.

00:52It can be a turbine, a steam turbine, etc.

00:55The power transmission is connected to two metal slip rings which rotate together,

01:00and the slip ring is connected to the brush so that current can be transmitted.

01:05When the rate of change of the magnetic flux is zero, no current will be generated.

01:09However, as the power transmission rotates, the magnetic flux begins to change,

01:15forming a current through four quarters of a cycle.

01:18After the change of the magnetic flux reaches the maximum value,

01:21the current also reaches the maximum value.

01:24As the power transmission continues to rotate, the change of the magnetic flux gradually decreases,

01:30so the current also decreases.

01:32When the yellow power transmission part reaches the bottom,

01:35the power transmission is parallel to the magnet,

01:37resulting in a change rate of zero for the magnetic flux.

01:41At this time, the current is also zero.

01:43The current change in the second half of the cycle is the same as that in the first half,

01:48but the current direction is exactly opposite.

01:50The curve of the entire cycle is like this.

01:53This is alternating current.

01:55The biggest difference between alternating current and direct current is the direction of current.

02:00In order to prevent the change of current direction in the DC generator,

02:04only one ring called a split ring is used in the slip ring part.

02:08However, the friction between the brush and the armature in the DC generator can easily cause wear.

02:14The above is just theory, but in practical applications it will be much more complicated.

02:19This is a small disassembled DC generator.

02:22The middle part is the armature.

02:23There are two permanent magnets on the outside.

02:26A metal coil is wrapped around the armature.

02:29When the armature rotates, the coil cuts the magnetic field to generate electricity,

02:34but it needs to be noted that it is not that easy to use in large power plants.

02:39First of all, due to energy transmission efficiency and transmission distance,

02:44most power plants use alternators.

02:46In order to generate 150 megavolt amperes of electricity,

02:50the generator will have a very high speed, reaching 3000 rpm.

02:55If we were to place the beam winding of such a large generator on the rotor like the small DC generator just now,

03:01it would be very dangerous.

03:03The noise in the surrounding area would be equivalent to an earthquake, so we have to change our thinking.

03:08We can place and fix the power transmission group on a nail.

03:11This will not only make it easier to provide cooling,

03:14but also make it easier to collect large voltages and currents.

03:18If this is the case, the rotor can only be designed as a magnet to provide a magnetic field,

03:23but the problem arises again.

03:25If a large generator is made of a permanent magnet, it is not suitable.

03:30First of all, it is difficult to install because the magnet is huge.

03:34It may suddenly be stuck somewhere and cause huge damage, and you can't separate it.

03:39Secondly, even if you use up all the energy, it may cause huge damage.

03:45Tiger Force installed it accurately on the rotor.

03:48Another problem is that the magnetism of the permanent magnet will slowly decrease over time.

03:54The magnetism cannot be controlled, but there are ways.

03:57We all know that when a metal coil is connected to DC,

04:00the coil will generate a magnetic field exactly the same as that of a permanent magnet,

04:05and we can control its magnetic field by controlling its power supply.

04:09Now we install a winding on the rotor that can generate a magnetic field,

04:14which is also called a particle winding.

04:16Then, when DC current is applied, a constant magnetic field is generated.

04:21At this time, we use a turbine to provide mechanical power to the rotor.

04:25For better observation, we first show only one set of coils on the stator winding.

04:30When the rotor rotates, the magnetic field lines cut the stator winding.

04:35The stator winding will produce an electric waveform formed by the change of the magnetic flux.

04:41The simple model we talked about at the beginning of the video is the same.

04:44The difference is that now we have three sets of windings on the nail.

04:49The phase angles of the three windings are all 120 degrees.

04:53When the rotor rotates, the three windings produce electricity at the same time.

04:58This is the so-called three-phase.

05:00However, this kind of rotor is only suitable for use in slow-speed power generation equipment,

05:05such as hydroelectric power generation and wind power generators,

05:10because the gap between its magnetic poles is large.

05:13High-speed rotation will cause imbalance and even cause the generator to fall apart.

05:18For example, the rotor in a thermal generator is set into two magnetic cylindrical rotors

05:23to meet the high-speed rotation of 3,000 revolution per minute,

05:27and the rotor rotation speed determines the frequency of the power grid.

05:31In many chargers, you will find 50 to 60 Hertz.

05:35The word Hertz is the grid frequency.

05:37It depends on the national or regional standard.

05:40The grid frequency in most countries is 50 Hertz.

05:43Its calculation formula is the generator magnetic set number

05:47multiplied by the generator speed and divided by the constant 120.

05:51So, next time you see a generator, you'll know it's not just a box making electricity.

05:57It's a marvel of simplicity, wrapped in coils and magnets doing the electric boogie.

06:02If you found this journey through the world of generators electrifying,

06:05don't just keep it to yourself.

06:07Spread the wattage by liking, commenting, sharing, and subscribing to keep the sparks flying.

06:12Let's power up together.

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