RECTIFIER & DC sYSTEMS
Rectifier (Rectifier) is an electronic circuit used to convert AC current (alternating current) to DC current (direct current) with the help of semiconductor materials. The process of converting the alternating current into a direct current is called “Straightening”. All rectifiers are made by connecting multiple diodes together in a specific way to make it possible to convert AC to DC more efficient than a single diode. Straightening is carried out via semiconductor diodes.
Capacitors can also be used in rectifier circuits by discharging the accumulated energy into the load. The voltage graph obtained for a device operating with DC voltage is not suitable. Because what the device wants is a flat and smooth voltage that can be obtained from a battery.
The following diagram shows the connection of a capacitor parallel to a load connected to a half-wave rectifier. As the voltage increases, the capacitor that stores the load starts to transmit the electrical charge inside the load when the voltage starts to drop. From this point on, while the AC voltage decreases, the capacitor acts as a source and discharges the load within it according to the impedance value in front. The graph of the voltage transmitted to the load becomes the upper voltage graph in the picture below. In the first case, this graph is closer to the DC voltage. This is more suitable for the smooth operation of a DC-powered tool.
Considering a stabilizing rectifier circuit, the voltage above has a maximum and a minimum. The difference between these two values is called ripple. The lower the amplitude of these wavelets, the closer the correct voltage value is.
The capacitance values of the capacitors used in the rectifier also affect the obtained voltage graph. When 3 capacitors with different capacities are connected to the same rectifier circuit, as the graph shows, the load voltage approaches DC voltage as the capacity value increases. This is because the capacity of the capacitor increases as the amount of load stored and this electrical charge feeds the load for a longer time. In short, as the capacitance values of rectifier capacitors increase, the approach to DC voltage is provided and the wavelength amplitude decreases.