WO2021242330A1 - Four or more poles on the rotor of three phase generators - Google Patents

Abstract

The nature or purpose of my invention is to make a modification to the existing three-phase generator in power plants. This invention in the generator consists of increasing the number of poles in its rotor, which reduces the cost of generating electricity. Furthermore, by reducing the cost of electricity generation, it also reduces the pollutants created by burning fuel.

Description

I. Title of Invention:

Four or more poles on the rotor of three phase generators.

II. Background:

This invention is related to the field of electrical energy and especially to the electrical energy generated in power plants. The field of electrical energy is a utility that everyone uses or consumes both in homes and in industries. Thanks to several factors, and especially to the increase in fossil fuel (oil, coal, natural gas, etc.), it caused the cost of production and consumption of electrical energy to increase progressively over decades.

This helped or caused consumers, of electrical energy, to become upset when paying the bill for the consumption of electrical energy. For this and other reasons, people have looked for other alternatives (solar, wind, water, etc.) to those already existing to generate electricity. And that is why I, as a consumer of electrical energy and with my knowledge of electricity, understand that the invention I'm proposing can help this problem.

My invention proposes to reduce the cost of the production of electrical energy by increasing the poles on the generator rotor, causing the cost of fuel consumption to be lower and therefore the consumer to see it reflected in the electricity bill.

III. Detailed Description of the Invention:

The invention that I propose for electric generators, is the increase of poles in the rotor. In general, power plants that use fossil fuels (oil, coal and natural gas) and nuclearfission, to create steam and move the turbine that is coupled to the generator, their electric generators have two (2) poles in the generator. If you look at Figure 1, it shows a representative diagram, not to scale of a two poles single phase generator. This figure shows how a DC source energizes a two poles bar which produces a magnetic field that creates a permanent magnet on the rotor with two poles (north and south). This permanent magnet in the rotor, when rotating with the magnetic field, "cuts" or creates a magnetic force in the Phase A conductor of the stator, generating a current and voltage at the generator output. The voltage frequency generated by this single-phase generator is represented in the graph in Figure 1. This graph shows a voltage at a frequency of 60 Hz or 60 cycles per second produced by a two poles generator that rotates at a speed of 3600 RPM (revolution per minute). In the following formula, the synchronous speed formula can calculate the number of turns that the generator rotor has to make to generate a current and voltage at a certain frequency: Synchronous Speed

RPM = Revolution Per Minute f = Frecuency p = Poles

Also, in the same Figure 1 shows the calculations, using the formula of the synchronous speed, to calculate the number of turns needed for a frequency of 60 Hz. Now if you look at Figure 2, a generator with two poles on the rotor is shown. This generator rotates its rotor at 3600 RPM generating a current and voltage at 60 Hz; but unlike Figure 1, it has three (3) phases in the stator producing a three-phase current and voltage. Figure 2 also shows the graph of the voltage frequency generated by that generator. If you look closely at the graph, it shows how the voltage behaves with the three phases of the stator. This type of three-phase generator generates voltage that the industry requires them to generate to prevent the voltage from reaching zero (0). Therefore, it can be said that Figure 2 is the representative diagram of a typical generator of a power plant which generates a current and voltage at the frequency established in the industries for the countries that require it to be generated at 60 Hz. In contrast, Figure 3 shows a generator which has six (6) poles in its rotor. It generates a three-phase current and voltage of 60 Hz but its rotor rotates at a speed of 1200 RPM, reducing by 67% the number of turns the rotor needs to generate the same current and voltage at 60 Hz. If you look at Table 1: Synchronous Speed with Different Number of Poles in the Rotor, this shows the number of turns that is reduced if the number of poles in the rotor is increased. This reduction of turns is going to reduce fuel consumption for the following reason. If the number of turns of the generator rotor is reduced, then the amount of steam used to rotate the turbine which is coupled with the rotor of the generator is reduced. By reducing steam, less water is necessary and therefore less fuel is needed to change water to steam. This reduction of rotations in the rotor is not proportional with the reduction of fuel, because there are many factors to consider, but it gives you an idea of how much fossil fuel consumption could be reduced in the generation of electricity. And a reduction of water to generate steam can also be mentioned. I have not carried out tests of my invention in any electrical system, because there are many factors, such as economics, materials, equipment, etc., but I understand that it can be done.

If all the factors are given to carry out my invention and it could be implemented in power plants, then new units could be created or units can be modified (changing the generator to increase capacity or changing the boiler) to be more efficient in the production of electricity and reducing pollutants in the atmosphere.

Claims

Patent Claim:

A three-phase generator, comprising:

• Four or more poles in the rotor of a three-phase generator for Power Plants.

This bring a more efficient generator in the economic and environmental aspect due to its reduction in cost for generation and the reduction of pollutants to the atmosphere by burning fuel.