How is the electricity generator made

The constant increase in the cost of electricity forces many to think about the need to organize an independent system of their own power supply. In addition, sometimes this is the only way to equip the electricity with the proper quality. The search for solutions to the problem of self-voltage stress leads to the need to understand how the generator is made. Although now there are quite a lot of revolutionary solutions that allow you to get electricity almost "out of nothing", they do not find practical application, being not always workable, giving way to a time-tested option with an electric motor.

The prerequisites for creating a generating device

To learn how to make the generator of electricity, it follows with the recollection of the basics of electrical engineering. In the section on engines, it is clearly stated that any of them can work not only as a consumer, converting the work of a charge into mechanical energy of shaft rotation, but also in the opposite mode, converting the mechanical moment to the potential at the terminals. This feature is called the law of reversibility of electrical machines. Actually, this is the basis of how the generator is made.

Engines

When choosing an electric motor, you should know that they can be DC or AC. Since considering the way a generator is made, it is often meant to be a "change", then we will not talk about a "constant". Alternating current machines exist in variations with a phase and squirrel-cage rotor. In the first case, the ends of the windings are led to a special device with a set of contact pads, the supply of power to which is carried out using graphite brushes. The use of such solutions as a generator is more difficult.

Principle of operation

To understand how a generator is made, it is necessary to represent the processes occurring in the engine during operation. Let us consider a three-phase model. When power is applied to the stator winding leads (stationary part), a magnetic field appears in it, the lines of tension intersect the closed winding of the rotor (rotating "drum"). Due to this, a current is induced in the latter, which generates its own magnetic field. The interaction of these two fields creates a torque. It's that simple.

Consequently, proceeding from the law of reversibility, it is necessary to untwist the rotor by an external action, and to remove tension from the stator windings. In generators sold in retail chains, torque creates a gasoline engine. Although the efficiency of such a system is small, it works.

A few nuances

People who have already studied how the generator is made know that there are a number of features of the connected circuits. Having unscrewed the shaft and connected the load to the terminals, it will not be possible to fully open the potential of the device. The reason for this lies in the fact that the current does not arise in the windings of the rotor (the magnetization is small and extinct). To solve this problem, an efficient solution is used: a block of capacitors included in a triangle is placed between the three terminals of the three-phase motor in question. That is, to each corner the wire from the stator winding terminal is fed, from here there are three outputs to the load. Non-electrolytic capacitors, such as MBGT, MBGO, etc., should be used. Their voltage should be not less than 600 V. Capacity depends on the load (the more powerful it is, the higher the class of capacitors) and the characteristics of the engine. For example, for a 2 kVA generator, the battery capacity is at least 28 μF.

Without load, it is not recommended to use the generator because of the resulting heating. It should also be taken into account that for a three-phase electric motor, from which 220 V is removed in the generator mode, the power will be one-third of the rating.

The speed of rotation of the shaft must be not lower than synchronous. Otherwise, there is a decrease in frequency and / or voltage.

Most often people have a question: "How to make a wind generator?" Everything is logical: the wind is a free resource that is always available. This solution includes: engine; Blades on the shaft, adjusted to a certain angle; Block of capacitors. If the low-voltage output is initially planned, an inverter and a rechargeable battery will additionally be required.