One of the basic elements in modern electronics is a diode. It is used in circuits where AC rectification is necessary, and is used in almost all household appliances. You can find it on a TV, computer, refrigerator, tape recorder, etc. It is also widely used in industrial electronics, and is part of the circuits that control technological processes. Powerful power diodes are used in semi-controlled thyristor converters. On the basis of the diode, the so-called Goertz circuit is assembled, which is called the diode bridge. The connection of the diodes in a bridge circuit made it possible to rectify an alternating voltage and convert it to a pulsating one, which can then be stabilized and rectified using voltage stabilization circuits and capacitors. As a result, a constant voltage can be obtained at the output of such a device.
In the days of Leo Goertz, using a diode bridge was problematic, since the diodes at that time were tube. Putting four lamps on AC rectification at once was at least impractical, at that time they were very expensive. The situation has changed a lot with the advent of
semiconductor devices, they are much more compact and cheaper.
Assemble diode
you can bridge yourself, for example, for your own home laboratory. To do this, we select four diodes with a permissible reverse voltage of 400-500 volts. We connect the cathodes of one pair of diodes together - this will be a positive output of the bridge. The anodes of the second pair are also connected together - this, respectively, is the negative output. Now we combine two pairs in a bridge circuit, alternating voltage can be applied to the remaining two outputs. At the output of the diode bridge we solder the polar capacitor and parallel to it is the discharge resistance. It turned out a diode bridge, which can be mounted on a desktop and connected via a variable high-impedance resistance to the mains. The output voltage of such a device will be regulated from zero to the magnitude of the amplitude value of the supply network, which is very convenient for supplying low-power circuits during commissioning or for creating a reference voltage.
Also, the bridge circuit is used in the car, the so-called diode bridge of the generator is used here. It is used to convert the alternating voltage generated by the generator into direct voltage, which is used in all devices of the car. Constant voltage is also needed to recharge the car battery. The failure of even one element of the diode bridge leads to unstable operation of the entire circuit.
For DC welding, the use of a diode bridge is also necessary. In this case, diodes of greater power are used than in a car, and with a large allowable value of the reverse voltage. The diode bridge for the welding machine can be assembled independently using powerful diodes. The class of diodes is selected depending on the supply voltage received from the welding transformer.