Relay-voltage regulator VAZ-2107: the principle of operation and varieties

Relay-voltage regulator VAZ-2107 is necessary forstable operation of all electricity consumers. It is more correct to call it a regulator without adding a “relay”, since modern cars are equipped with electronic devices based on semiconductors. And the electromagnetic relay in the design is missing. But just by the example of a mechanical regulator it is necessary to consider the operation and the principle of operation of the device.

What is the regulator necessary for?

On automobiles, generator sets are used that produce alternating three-phase voltage. After this, the following transformations take place:

1. Three phases are fed to a rectifier unit of six silicon diodes.
2. Each phase is rectified and voltage is converted to a constant unipolar one.
3. The entire variable component is cut off with an electrolytic capacitor.
4. Rectified voltage is applied to the power contact in the back of the generator.

The voltage depends on the rotational speed, since the generator output can be 10 V at 1000 rpm and 30 V at 7000 rpm (if you do not use a regulator).

Therefore it is necessary to stabilize the voltage.The method used in household appliances, the installation of a simple zener diode, is not suitable. The power of the generator is very high, the current is over 50 A. If you can find such a stabilitron in nature, then it will not be inferior to the size of a car engine. The cost of producing such a device is very high. Photo relay voltage regulator VAZ-2107 can be seen in the article.

But there is a basic requirement for the operation of any generator set:

An electric current can be generated in the stator winding only if it is affected by a constant magnetic field.

Чтобы создать магнитное поле, нужно на обмотку rotor energize. And in order to make the magnetic field constant, it is enough to stabilize the supply circuit of the excitation winding. And she has a maximum current consumption of not more than 2.6 A. It is much easier to stabilize.

Electromechanical devices

They have not been used for several decades, since they have significant drawbacks:

1. A small resource.
2. The need for frequent maintenance.
3. Massive construction.

The main components of the device:

1. Electromagnetic relay.
2. Thermal compensating resistance.
3. Throttle.
4. Additional resistors - 2 pcs.

The anchor is fixed with a yoke to the bimetallic plate. Such a relay-voltage regulator VAZ-2107 (carburetor in the injection system) were completed the first editions of the model.

The processes in the regulator when the engine is stopped

The whole cycle of the device can be divided into several stages:

1. As soon as the ignition is switched on, current is supplied from the battery to the core of the choke.
2. The current also passes through the normally closed contacts and is applied to the “W” terminal of the regulator.
3. The target is the excitation winding. It is powered when the ignition is turned on.
4. The voltage enters through the contact "I" to the resistance of thermal compensation and the winding of the regulator, the second end of which is connected to ground.
5. While the magnetizing force at the core is insignificant, the contacts K1 are closed, a current passes through the rotor field winding. Its value is about 2.6 Ampere.
6. In this case, the current enters the switch in the ignition lock, normally closed contacts, clamp, lamp in the dashboard, relay for controlling charging.

When starting the engine

As soon as the engine is started, the following processes occur:

1. Magnetization of the core.
2. The force of the spring is overcome, and the group of contacts K1 opens.
3. The first stage of adjustment is switched on.
4. Electric current is supplied to the inductor and additional resistance (R ext = 5.5 Ohm).
5. The current in the rotor winding gradually increases, and the voltage decreases.
6. Contact group K1 closes.

The process repeats again, the anchor vibrates andconstantly closes and opens the contacts. The voltage on the excitation winding is fed, then no. When the rotor rotates very quickly, a small resistance is included in its winding circuit - as a result, the voltage rises to a maximum of 14.6 volts. The magnitude of the current in the winding increases to such a value that the second group of contacts K2 is attracted. At the same time, the second step of voltage adjustment is put into operation.

Features of semiconductor structures

All the above processes can be applied toelectronic controllers based on semiconductors. Here are the functions of the power contacts transistors took over. In total, there are two types of electronic devices:

1. Contact transistorwhich are a symbiosis of a mechanical and electronic regulator. The reliability of devices of this type still leaves much to be desired, since there are mechanical elements in the design.
2. Fully contactless - made on a modern electronic base. Allow you to more effectively carry out voltage regulation in the onboard network.

Some motorists do not know where they are.relay voltage regulator VAZ-2107. On new machines, it is mounted directly in the generator housing in the same node with brushes. On older versions of cars, they were installed in the engine compartment, connected to the brush mechanism by wires.