Research on Single-Phase Bridge Rectifier Circuit Based on MATLAB

1 Introduction

Rectifier circuit, especially single-phase bridge controlled rectifier circuit, is the most important and widely used circuit in power electronics technology. It is not only used in general industry, but also widely used in other fields such as transportation, power system, communication system, energy system, etc. Therefore, it is of great practical significance to compare and analyze the relevant parameters of single-phase bridge controlled rectifier circuit and the working conditions of loads of different properties. It is not only an important part of the theoretical study of power electronic circuits, but also has a predictive and guiding role in the actual application of engineering practice.

2 Single-phase bridge semi-controlled rectifier circuit

In Figure 1, VT1 and VT2 are thyristors with a trigger pulse phase difference of 180°, VD1 and VD2 are rectifier diodes, and these four devices form a single-phase bridge semi-controlled rectifier circuit. The resistor R and the inductor L are the loads. If the inductor L is assumed to be large enough, that is, ωL≥R, since the current in the inductor cannot change suddenly, it can be considered that the load current remains constant during the entire steady-state operation. Due to the characteristics of the bridge structure, as long as the thyristor is turned on, a forward voltage is always applied to the load, and the load current always flows in one direction. Therefore, the bridge half-controlled rectifier circuit can only work in the front quadrant. Because ωL≥R, no matter what the control angle α is, the load current id changes very little.