CN107359783A - A kind of multi-functional convertor circuit and its control method - Google Patents

Abstract

A multifunctional inverter circuit and its control method. The structure of the present invention is composed of five switch tubes, inductors, capacitors, and loads. Through the control of the switch states of each switch tube, it is divided into two major working modes and their respective specific switch tubes. The switch control method can realize the output of forward DC, reverse DC, and AC power, and the voltage and current values can be adjusted, and the AC output frequency can be adjusted, so as to realize a low-cost, simple-structured multifunctional power supply device. The field of light weight and low cost has application prospects.

Description

A multifunctional inverter circuit and its control method

technical field

The invention relates to the field of small power supplies, in particular to a single-structure multifunctional power converter circuit capable of realizing AC and DC output and adjustable in size and a control method thereof.

Background technique

With the development of power electronics technology, various AC and DC power supplies are required by all walks of life.

In some fields, especially aircraft, automobiles, field engineering construction and other fields, it is necessary to have as light equipment and as small a volume as possible, and a comprehensive power supply, that is, it can not only provide direct currents of different sizes in different directions, but also provide different frequencies and Integrated power supplies with large and small alternating currents are bound to be welcomed; at the same time, integrated power supplies with low prices are also necessary for the development of the industry.

Contents of the invention

According to the above background technology, the present invention proposes a converter main circuit with a simple structure that can output direct current and realize positive and negative direction and adjustable voltage and current, and can also output alternating current and adjustable frequency and voltage and current. and its control methods.

Technical scheme of the present invention is:

A multi-functional inverter circuit, which is composed of five switching tubes, inductors, capacitors, and loads. Its technical feature is that the anode of the first switching tube is used as the input positive terminal, and the cathode of the first switching tube is connected to the second switch tube cathode, the third switch tube cathode, one end of the inductor, the other end of the inductor is connected to the fourth switch tube anode and the fifth switch tube anode, the third switch tube anode is connected to the fifth switch tube cathode, the One end of the capacitor, one end of the load, the other end of the load, the other end of the capacitor, the cathode of the fourth switch tube, and the anode of the second switch tube are short-circuited and used as the input negative terminal.

A control method for a multifunctional inverter circuit, the technical feature of which is that the multifunctional inverter circuit of the present invention has two working modes;

Mode 1: forward voltage transformation mode;

In this mode, the second switching tube and the fifth switching tube remain in the closed state, the third switching tube remains in the open state, and the switching control methods of the first switching tube and the fourth switching tube are subdivided into two types:

(1) The fourth switching tube remains in the off state, and the first switching tube works in a PWM mode;

(2) The first switching tube remains closed, and the fourth switching tube operates in a PWM mode;

Mode 2: reverse voltage transformation mode;

In this mode, the third switching tube and the fourth switching tube are kept closed, the second switching tube and the fifth switching tube are kept open, and the first switching tube works in PWM mode;

When mode 1 and mode 2 work alternately, the load gets AC power.

Technical effect of the present invention mainly contains:

The current conversion device composed of the current conversion circuit of the present invention is not only a DC/DC converter, but also a DC/AC inverter; when only one mode works alone, it is a DC/DC converter, and can realize direct current in different directions The size of the output can be adjusted; when the two modes work alternately, it becomes a DC/AC inverter, and the inverter frequency, voltage, and current can be adjusted; in addition, in some special fields, when positive inverters of different sizes are required When reverse alternating current, the present invention can also be realized, because can control the output voltage and the electric current when two modes work respectively; And the realization of above all these functions, the main circuit that it bears namely the structure of the present invention is very simple, and cost is naturally low .

Description of drawings

Fig. 1 is a structural diagram of a multi-functional inverter circuit of the present invention.

detailed description

A multifunctional converter circuit, as shown in Figure 1, is composed of five switch tubes, an inductor L, a capacitor C, and a load R. The anode of the first switch tube V1 is used as the input positive terminal, and the cathode of the first switch tube V1 is connected to The cathode of the second switching tube V2, the cathode of the third switching tube V3, one end of the inductor L, the other end of the inductor L is connected to the anode of the fourth switching tube V4 and the anode of the fifth switching tube V5, and the anode of the third switching tube V3 is connected to the cathode of the fifth switching tube V5 , one end of the capacitor C, one end of the load R, the other end of the load R, the other end of the capacitor C, the cathode of the fourth switching tube V4, and the anode of the second switching tube V2 are short-circuited and used as the input negative terminal;

The control method of the multifunctional inverter circuit in the embodiment of the present invention has two working modes;

Mode 1: forward voltage transformation mode; in this mode, the second switching tube V2 and the fifth switching tube V5 remain in the closed state, the third switching tube V3 remains in the open state, and the first switching tube V1 and the fourth switching tube V4 The switch control method is subdivided into two types:

(1) The fourth switching tube V4 remains in the off state, and the first switching tube V1 works in a PWM mode; wherein, when the first switching tube V1 is closed, the input direct current supplies power to the load R through V1-L-V5 and simultaneously supplies power to the load R The capacitor C is charged. When the first switch tube V1 is disconnected, the energy stored in the inductor L supplies power to the load R and the capacitor C via V2-L-V5. Adjusting the duty cycle of the first switch tube V1 changes the direction to The average voltage and average current value of the load R power supply;

(2) The first switching tube V1 remains in a closed state, and the fourth switching tube V4 switches and operates in a PWM mode; wherein, when the fourth switching tube V4 is closed, the input direct current charges and stores energy to the inductor L through V1-L-V4, The electric energy in the capacitor C supplies power to the load R. When the fourth switch tube V4 is turned off, the input direct current and the energy storage of the inductor L jointly supply power to the load R and charge the capacitor C at the same time. The path is V1-L-V5-C/ R; adjust the switching duty cycle of the fourth switching tube V4, and change the average voltage and average current value of the power supply to the load R;

It can be seen that the direction of the current of the load R under the two working conditions in the forward transformation mode is the same, and its direction is defined as the forward direction.

Mode 2: reverse voltage transformation mode; in this mode, the third switch tube V3 and the fourth switch tube V4 remain in the closed state, the second switch tube V2 and the fifth switch tube V5 keep in the open state, and the first switch tube V1 is pressed PWM mode switch operation; wherein, when the first switch tube V1 is closed, the input direct current supplies power to the inductor L through V1 to store energy, and at the same time, the capacitor C supplies power to the load R. When the first switch tube V1 is turned off, the inductor L The energy stored in the battery is released to the load R and capacitor C along V3-L-V4; it can be seen that the direction of the current flowing through the load R is completely opposite to that of the previous mode 1, which is reverse; by adjusting the switching duty of the first switching tube V1 Ratio, changing the average value of the reverse current voltage supplied to the load R.

When mode 1 and mode 2 work alternately and isochronously according to the law, the load R receives alternating current, and the alternating frequency of mode 1 and mode 2 is equal to the frequency of alternating current on the load R; when only mode 1 works, the load R receives positive direct current, When only mode two works, the load R receives reverse direct current.

Each switching tube in this embodiment adopts fully controlled power electronic switching devices such as MOSFET or IGBT; although the load in this embodiment is a resistor R, loads that do not interfere with other properties are also within the protection scope of the present invention.

Claims (2)

1. A multifunctional converter circuit, consisting of five switching tubes, an inductor, a capacitor, and a load. Its technical feature is that the anode of the first switching tube is used as the input positive terminal, and the cathode of the first switching tube is connected to the first switching tube. The cathode of the second switch tube, the cathode of the third switch tube, one end of the inductor, the other end of the inductor is connected to the anode of the fourth switch tube and the anode of the fifth switch tube, the anode of the third switch tube is connected to the cathode of the fifth switch tube, One end of the capacitor, one end of the load, the other end of the load, the other end of the capacitor, the cathode of the fourth switch tube, and the anode of the second switch tube are short-circuited and used as the input negative terminal. 2. A control method for a multifunctional converter circuit, its technical feature is that the multifunctional converter circuit of the present invention has two operating modes; Mode 1: forward voltage transformation mode; In this mode, the second switching tube and the fifth switching tube remain in the closed state, the third switching tube remains in the open state, and the switching control methods of the first switching tube and the fourth switching tube are subdivided into two types: (1) The fourth switching tube remains in the off state, and the first switching tube works in a PWM mode; (2) The first switching tube remains closed, and the fourth switching tube operates in a PWM mode; Mode 2: reverse voltage transformation mode; In this mode, the third switching tube and the fourth switching tube are kept closed, the second switching tube and the fifth switching tube are kept open, and the first switching tube works in PWM mode; When mode 1 and mode 2 work alternately, the load gets AC power.