However, if the same current is to be output, the wire diameter of the winding should be thickened accordingly. To achieve full-wave rectification, in this structure, if the same DC voltage is output, the secondary winding of the transformer needs only half of the winding compared with full-wave rectification. It can be seen from the figure that in the positive half cycle, the current is guided by D1 and D3 to pass through RL from top to bottom, and in the negative half cycle, the current flows by D2 and D4 to pass through RL from top to bottom. The specific connection method is shown in the figure. Using the guiding function of the diode, the secondary output can be directed to the load even in the negative half cycle. D1 ~ D4 are four identical rectifier diodes connected in the form of a bridge, so they are called bridge rectifier circuits. The transformer windings are connected to four diodes according to the method above. The bridge rectifier circuit can also be considered as a kind of full-wave rectifier circuit. To simplify, the diode is treated with an ideal model, that is, the forward conduction resistance is zero and the reverse resistance is infinite. If you choose improperly, you may not be able to work safely, or even burn the diodes.Ĥ How Bridge Rectifier Converts AC to DC? It needs to be pointed out that the diode as a rectifier component should be selected according to different rectification methods and load requirements. With the rapid development of semiconductor devices and low cost today, bridge rectifier circuits are widely used in practice.
The bridge rectifier circuit overcomes the shortcomings that the full-wave rectifier circuit requires the transformer secondary to have a center tap and the diode have to withstand large back pressure, but two more diodes are used. The main parameters of bridge rectifier circuit calculation. So bridge rectifier is an improvement on diode half-wave rectifier. It is not difficult to see from the Figure 1 that the reverse voltage of each diode in this bridge circuit is equal to the maximum value of the secondary voltage of the transformer, which is half smaller than the full-wave rectifier circuit. In the negative half cycle of u2, D1 and D3 are off, and D2 and D4 are on. In the positive half cycle, D1 and D3 are on, D2 and D4 are off. 2 What Bridge Rectifier Consist of? 2.1 How Does Bridge Rectifier Work?įigure 1.
Limit the battery current to flow back to the generator to protect the generator from being burnt out by the reverse current. The bridge rectifier circuit uses the unidirectional conductivity of the diodes, divides the four diodes into two groups, and conducts respectively according to the polarity of the transformer secondary voltage, and connects the positive terminal of the transformer secondary voltage to the upper terminal of the load resistance, the negative terminal is connected to the lower end of the load resistance, so that a unidirectional pulsating voltage can always be obtained on the load.īridge rectifier circuit is powerful. Bridge Rectifier converts the alternating current generated by the alternator into direct current to supply power to electrical equipment and components.