1. According to whether there is electrical isolation between input and output: non-isolated DC converter with isolated DC converter.
2. Non-isolated DC converters are classified according to the number of active power switching devices: single tube, double tube and four tube.
There are six types of single-tube DC converters, namely, a buck converter, a boost converter, a buck-boost converter, a Cuk converter, a Zeta converter, and a Sepic transform. And so on. Among the six single-tube converters, buck and boost converters are the most basic, and the other four are derived from them.
The dual-tube DC converter has a double-tube series-connected Buck/Boost converter.
Four-tube DC converter such as Full-bridge converter
3. Isolated DC converters can be classified by the number of active power switching devices. There are two types of single tubes: Forward and Flydack.
The double tube has four types of double tube forward, double tube flyback, push pull and half bridge. Four-tube DC converter timely full-bridge DC converter.
The isolated converter can realize the electrical isolation between the input and the output. Usually, the transformer is used for isolation. The transformer itself has the function of voltage transformation, which is beneficial to expand the application range of the converter. The application of the transformer also facilitates the output of multiple voltages.
When the voltage and current rating of the power switch tube are the same, the output power of the converter is usually proportional to the number of switches used, so the output power of the four-tube converter is the largest, and the output power of the single-tube converter is the smallest.
No single converter can be combined with an isolated converter to obtain characteristics that are not available in a single converter.
4. According to the energy transfer, the DC converter has one-way and two-way. The charger with bidirectional function charges the battery when the power is normal. Once the power is interrupted, it can return the battery power to the grid and supply power to the grid for a short period of time. The DC motor control converter is also bidirectional. When the motor is working, the electric energy is transmitted from the power source to the motor, and the motor power is fed back to the power source during braking.
5. DC converters are also divided into self-excited and other controlled. The converter that realizes the self-sustaining periodic switching of the switch by means of the positive feedback signal of the converter itself is called a self-excited converter, and the Loyer converter is a typical push-pull self-excited converter. The switching device control signal in his controlled DC converter is generated by a special control circuit.