CN105915047A - Novel direct current boosted circuit - Google Patents

Abstract

The invention provides a novel DC boost circuit, comprising: a DC voltage source, a voltage doubling module, a Boost circuit module and a load module; after the DC voltage source is boosted by a plurality of voltage doubling modules charged in parallel and discharged in series, The Boost circuit boosts the voltage again and transmits it to the load module. The rated voltage that the switching tube in the DC boost circuit provided by the present invention must bear does not exceed the peak value of the input voltage, the voltage doubler circuit can raise the low voltage to a higher voltage required, and the Boost circuit can regulate the voltage The function makes the output voltage continuous, and the performance is more stable and reliable; and can meet the voltage requirements of different levels by adding a voltage doubler module, and has strong versatility.

Description

A New Type of DC Boost Circuit

technical field

The present invention relates to the technical field of DC-DC conversion, in particular to a novel DC boost circuit.

Background technique

Most systems have only one power supply. When different levels of voltage are required, they need to be obtained with the help of buck-boost circuits. Usually, the voltage level of the DC voltage source is low, but in the actual application process, some electrical equipment may require a higher level of voltage. At this time, various methods must be used to achieve the purpose of boosting.

Transformer is a common equipment for AC step-up. Adding a large capacitor to the output of the transformer can obtain a large voltage gain, but the transformer is bulky, and the magnetic core used will greatly increase the overall quality of the device. High frequency is an important method to reduce the size of the transformer. Firstly, the direct current is converted into high-frequency alternating current. The transformer generates high voltage on the secondary side through magnetic coupling, and then rectifies it to obtain the required DC high voltage output. The on-off rate of the tube is also a big test, and the whole process requires more equipment, and the control is more complicated. If the input voltage is low, the voltage loss is serious, and the energy transmission efficiency is not very high.

The direct current is converted into alternating current, and the direct current high voltage output can be realized through the voltage doubler rectification circuit, but the output voltage is poorly adjustable, and the highest reverse voltage that the rectifier diode in the circuit needs to withstand is twice the amplitude of the input voltage. When a very high output voltage is to be obtained, the diode may be reversely broken down.

High-voltage pulse generators are often used in high-voltage systems to obtain DC high voltages. This method can effectively obtain high-amplitude pulsed high voltages. But its shortcomings are also obvious. First, the existence of the ball gap makes the device bulky, and it is difficult to boost the voltage of a low-level DC voltage source; second, the output of the voltage is not continuous, which is not applicable in many occasions.

Boost circuit and Buck-Boost circuit are the most commonly used topologies for DC boost in power electronics. The principle is simple and the control is not difficult. However, when these two circuits can work under high voltage gain conditions, it is easy to cause circuit instability, and the requirements for inductance will also be greatly increased.

Based on the above, the analysis of the existing boost circuit structure found that at the current stage, it is still necessary to introduce a new type of DC boost circuit with simple control, strong versatility, and high voltage gain. The stage is connected to the Boost circuit, which can not only boost the voltage again, but also obtain a continuous output voltage through the regulation of the Boost circuit.

Contents of the invention

Aiming at the defects in the prior art, the purpose of the present invention is to provide a novel DC boost circuit.

According to the novel DC boost circuit provided by the present invention, it includes: a DC power supply, a voltage doubler module, a Boost circuit module and a load module; the DC power supply charges a plurality of voltage doubler modules, and when the voltage reaches a set value, the The voltage doubler module provides the load module with a boosted DC voltage through the Boost circuit module.

Preferably, the voltage doubler module includes: a capacitor, a first unidirectional thyristor, a second unidirectional thyristor, and a bidirectional thyristor; the positive pole of the capacitor constitutes the positive charging terminal of the voltage doubler module, and the negative pole of the capacitor constitutes the negative pole of the voltage doubler module. charging terminal; the positive pole of the capacitor is respectively connected to the anode of the first unidirectional thyristor and the anode of the bidirectional thyristor; the negative pole of the first unidirectional thyristor constitutes the first output terminal of the voltage doubler module, and the negative pole of the capacitor is connected to the second unidirectional thyristor The cathode of the thyristor, the anode of the second unidirectional thyristor is connected to the cathode of the bidirectional thyristor and constitutes the second output terminal of the voltage doubler module.

Preferably, a plurality of voltage doubling modules are serially connected in series to form a multi-stage voltage doubling module, that is, the first output terminal of the upper-level voltage doubling module is connected to the positive charging terminal of the next-level voltage doubling module, and the second output terminal of the upper-level voltage doubling module The output terminal is connected to the negative charging terminal of the next-stage voltage doubler module.

Preferably, the positive charging terminal of the primary voltage doubler module is connected to the positive pole of the DC power supply, the negative charging terminal of the primary voltage doubler module is connected to the negative pole of the DC power supply; the first output terminal of the final stage voltage doubler module is connected to the Boost circuit module The first input end of the final stage voltage doubler module is a non-connection end.

Preferably, the Boost circuit module includes: an inductor L1, a diode D1, a switch tube S1, and an electrolytic capacitor E4. One end of the inductor L1 constitutes the first input end of the Boost circuit module, and the other ends of the inductor L1 are respectively connected to The anode of the diode D1 and the drain of the switch tube S1, the cathode of the diode is connected to the anode of the electrolytic capacitor E4 and constitutes the first output terminal of the Boost circuit module, and the cathode of the electrolytic capacitor E4 is respectively connected to the source of the switch tube S1 pole, the negative pole of the DC power supply and constitute the second output end of the Boost circuit module; the first output end and the second output end of the Boost circuit module are respectively connected to the two ends of the load module.

Preferably, when the first unidirectional thyristor and the second unidirectional thyristor in each voltage doubling module are in the on state, and the bidirectional thyristor and the switch S1 are in the off state, the DC power supply is connected in parallel to each voltage doubling module. The capacitor is charged; when the first unidirectional thyristor and the second unidirectional thyristor in each voltage doubler module are in the cut-off state, and the bidirectional thyristor and the switch S1 are in the conduction state, the capacitors of each voltage doubler module are connected in series and are connected to each other. The inductance L1 is charged; when the first unidirectional thyristor, the second unidirectional thyristor, and the switch S1 in each voltage doubler module are in the off state, and the bidirectional thyristor is in the conduction state, the capacitance and the inductor L1 of each voltage doubler module are connected in series relationship and supply power to the electrolytic capacitor E4 and the load module.

Preferably, the switching tube S1 is an N-channel MOSFET device, 600V, 25A/100°C.

Compared with the prior art, the present invention has the following beneficial effects:

1. The rated voltage required to withstand the switch tube of the voltage doubler module in the DC boost circuit provided by the present invention does not exceed the peak value of the input voltage, and is far lower than the output voltage, and the circuit performance is more stable and reliable.

2. The novel DC boost circuit provided by the present invention can meet different levels of voltage requirements by adding a voltage doubler module, and has high voltage gain.

3. The novel DC boost circuit provided by the present invention can generate continuous DC high voltage through the adjustment of the Boost circuit module.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

Figure 1 is a schematic structural diagram of a 3-stage DC boost circuit;

FIG. 2 is a schematic structural diagram of an n+1 stage DC boost circuit.

detailed description

The present invention will be described in detail below in conjunction with specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

According to the novel DC boost circuit provided by the present invention, it includes: a DC power supply, a voltage doubler module, a Boost circuit module and a load module; the DC power supply charges a plurality of voltage doubler modules, and when the voltage reaches a set value, the The voltage doubler module provides the load module with a boosted DC voltage through the Boost circuit module.

The voltage doubling module includes: a capacitor, a first unidirectional thyristor, a second unidirectional thyristor, and a bidirectional thyristor; the positive pole of the capacitor constitutes the positive charging terminal of the voltage doubling module, and the negative pole of the capacitor constitutes the negative charging terminal of the voltage doubling module; The positive pole of the capacitor is respectively connected to the anode of the first unidirectional thyristor and the anode of the bidirectional thyristor; the negative pole of the first unidirectional thyristor constitutes the first output terminal of the voltage doubler module, and the negative pole of the capacitor is connected to the cathode of the second unidirectional thyristor , the anode of the second one-way thyristor is connected to the cathode of the two-way thyristor and forms the second output end of the voltage doubler module.

A plurality of voltage doubler modules are connected in series to form a multi-stage voltage doubler module, that is, the first output terminal of the upper-stage voltage doubler module is connected to the positive charging terminal of the next-stage voltage doubler module, and the second output terminal of the upper-stage voltage doubler module is connected to The negative charging terminal of the next stage voltage doubler module.

The positive charging terminal of the primary voltage doubler module is connected to the positive pole of the DC power supply, and the negative charging terminal of the primary voltage doubler module is connected to the negative pole of the DC power supply; the first output terminal of the final stage voltage doubler module is connected to the first of the Boost circuit module. The input terminal and the second output terminal of the final voltage doubling module are non-connected terminals and are not connected to other modules.

The Boost circuit module includes: an inductor L1, a diode D1, a switch tube S1, and an electrolytic capacitor E4. One end of the inductor L1 constitutes the first input end of the Boost circuit module, and the other end of the inductor L1 is connected to the diode D1 respectively. The anode and the drain of the switch tube S1, the cathode of the diode is connected to the anode of the electrolytic capacitor E4 and constitutes the first output terminal of the Boost circuit module, and the cathode of the electrolytic capacitor E4 is respectively connected to the source of the switch tube S1, the DC The negative pole of the power supply constitutes the second output terminal of the Boost circuit module; the first output terminal and the second output terminal of the Boost circuit module are respectively connected to the two ends of the load module.

When the first one-way thyristor and the second one-way thyristor in each voltage doubler module are in the on state, and the two-way thyristor and the switch tube S1 are in the off state, the DC power supply charges the parallel capacitors in each voltage doubler module ; When the first unidirectional thyristor and the second unidirectional thyristor in each voltage doubler module are in the cut-off state, and the bidirectional thyristor and the switch tube S1 are in the conduction state, the capacitors of each voltage doubler module are connected in series and charge the inductance L1 ; When the first one-way thyristor, the second one-way thyristor, and the switching tube S1 in each voltage doubler module are in the cut-off state, and the two-way thyristor is in the conduction state, the capacitance and the inductance L1 of each voltage doubler module are in a series relationship and are connected to each other. Electrolytic capacitor E4 and load module power supply.

The switch tube S1 is an N-channel MOSFET device, 600V, 25A/100°C.

Specifically, as shown in Figure 1, it is a three-stage DC boost circuit, the voltage doubler module can realize three-stage DC boost, and the Boost circuit module can boost the voltage again and make the output voltage continuous, including a power diode D1, an inductor L1, one N-channel MOSFET S1, four one-way thyristors TH1-TH4, two two-way thyristors BTH1-BTH2, four electrolytic capacitors E1-E4, load resistor RL, where:

The positive pole of the electrolytic capacitor E1 is connected to the anode of the thyristor TH1 and BTH1 and constitutes the positive charging terminal of the voltage doubler module, the negative pole of E1 is connected to the cathode of the thyristor TH2 and constitutes the negative charging terminal of the voltage doubler module; the cathode of the thyristor TH1 is connected to the electrolytic capacitor The positive pole of E2, the anode of thyristor TH3 and BTH2; the anode of thyristor TH2 is connected with the cathode of thyristor BTH1 and TH4, and the cathode of electrolytic capacitor E2; the cathode of thyristor TH3 is connected with the positive pole of electrolytic capacitor E3 and inductor L1; the negative pole of electrolytic capacitor E3 Connected to the anode of thyristor TH4, the cathode of thyristor BTH2;

The other end of the inductor L1 is connected to the drain of the MOSFET S1 and the anode of the power diode D1, the cathode of the power diode D1 is connected to the positive pole of the electrolytic capacitor E4, and one end of the load, and the source of the MOSFET S1 is connected to the negative pole of the electrolytic capacitor E4 and the load. The other end is connected and connected with the negative charging end of the primary voltage doubler module to form a loop.

The selection of the above components in this example:

Power supply: DC power supply 30V;

Load power: 8.1W,

Inductance (L1): 600V, 3300μH;

Power diode (D1): 600V, 25A/100℃;

One-way thyristor (TH1-TH4) and two-way thyristor (BTH1-BTH2): 600V, 25A/100℃;

Electrolytic capacitor (E1～E4): 600V, 3300μF, plug-in, used for energy storage and voltage doubling;

MOSFET(S1): 600V, 25A/100℃, used for switching of Boost circuit;

Load resistance (RL): 1kΩ/100℃, 10W;

When the whole circuit works specifically:

Turn on the DC power supply (30V), turn on the thyristors TH1-TH4, turn off the one-way thyristors BTH1-BTH2, and charge the electrolytic capacitors E1-E3 with the DC power supply. After the charging is completed, turn off the thyristors TH1-TH4 and turn on the two-way thyristor BTH1 -BTH2, electrolytic capacitor E1, bidirectional thyristor BTH1, electrolytic capacitor E2, bidirectional thyristor BTH2, and electrolytic capacitor E3 form a series connection. When MOSFET S1 is turned on, it charges the inductor. The electrolytic capacitor E4 and the load resistor RL provide a high voltage output that is multiple times the capacitor voltage. By adjusting the on and off times of the thyristors and MOSFETs, a continuous voltage output can be generated.

The working principle of the multi-stage DC boost circuit is basically the same as that of the three-stage DC boost circuit.

The invention can be applied to a series of fields that require DC level conversion, such as electric vehicle power supply system, secondary side voltage regulation system of wireless power transmission equipment, etc. It can multi-fold DC boost function, has low voltage required by the switch tube, can be modularized, Can generate continuous output voltage and other advantages.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. In the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims (7)

1. A novel DC boost circuit, characterized in that it comprises: a DC power supply, a voltage doubler module, a Boost circuit module and a load module; the DC power supply charges a plurality of voltage doubler modules, and when the voltage reaches a set value The voltage doubler module mentioned later provides the boosted DC voltage to the load module through the Boost circuit module. 2. The novel DC boost circuit according to claim 1, wherein the voltage doubling module comprises: a capacitor, a first unidirectional thyristor, a second unidirectional thyristor, and a bidirectional thyristor; the positive pole of the capacitor constitutes The positive charging end of the voltage doubling module, the negative pole of the capacitor constitutes the negative charging end of the voltage doubling module; the positive pole of the capacitor is respectively connected to the anode of the first unidirectional thyristor and the anode of the bidirectional thyristor; the negative pole of the first unidirectional thyristor constitutes the doubler The negative pole of the capacitor is connected to the cathode of the second one-way thyristor, and the anode of the second one-way thyristor is connected to the cathode of the two-way thyristor to form the second output terminal of the voltage doubler module. 3. The novel DC boost circuit according to claim 1, characterized in that a plurality of voltage doubling modules are serially connected in series to form a multi-stage voltage doubling module, that is, the first output terminal of the upper-level voltage doubling module is connected to the next level The positive charging end of the voltage doubling module, and the second output end of the upper-stage voltage doubling module are connected to the negative charging end of the next-stage voltage doubling module. 4. The novel DC boost circuit according to any one of claims 1 to 3, characterized in that, the positive charging terminal of the primary voltage doubler module is connected to the positive pole of the DC power supply, and the negative charge terminal of the primary voltage doubler module The end is connected to the negative pole of the DC power supply; the first output end of the final stage voltage doubler module is connected to the first input end of the Boost circuit module, and the second output end of the final stage voltage doubler module is a non-connection end. 5. The novel DC boost circuit according to claim 4, wherein the Boost circuit module comprises: an inductor L1, a diode D1, a switch tube S1, and an electrolytic capacitor E4, and one end of the inductor L1 constitutes a Boost circuit The first input end of the module, the other end of the inductor L1 is respectively connected to the anode of the diode D1 and the drain of the switch S1, and the cathode of the diode is connected to the anode of the electrolytic capacitor E4 and constitutes the first output of the Boost circuit module terminal, the negative pole of the electrolytic capacitor E4 is respectively connected to the source pole of the switch tube S1 and the negative pole of the DC power supply to form the second output terminal of the Boost circuit module; the first output terminal and the second output terminal of the Boost circuit module are respectively Connect to both ends of the load module. 6. The novel DC boost circuit according to claim 5, characterized in that, when the first unidirectional thyristor and the second unidirectional thyristor in each voltage multiplying module are in a conduction state, and the bidirectional thyristor and the switching tube S1 When it is in the cut-off state, the DC power supply charges the parallel capacitors in each voltage doubler module; when the first unidirectional thyristor and the second unidirectional thyristor in each voltage doubler module are in the cut-off state, and the bidirectional thyristor and switch S1 When in the on state, the capacitors of each voltage doubler module are connected in series and charge the inductance L1; When in the conduction state, the capacitors and the inductor L1 of each voltage doubler module are connected in series and supply power to the electrolytic capacitor E4 and the load module. 7 . The novel DC boost circuit according to claim 5 , wherein the switch tube S1 is an N-channel MOSFET device, 600V, 25A/100°C.