CN102201737B - High-order energy gaining voltage conversion circuit - Google Patents

Abstract

The invention relates to a high-order energy gaining voltage conversion circuit, which consists of six bridge arms of three phases. Upper and lower bridge arms are connected by bridge arm reactors. Each bridge arm is formed by concatenating high voltage power modules. The high voltage power module comprises a high voltage module, a capacitor and high-order energy gaining equipment which are sequentially connected in parallel. The high voltage power modules of the high-order energy gaining voltage conversion circuit provided by the invention gain energy from high order, and realize wide-range voltage input.

Description

A high-level energy-taking voltage conversion circuit

technical field

The invention relates to a voltage conversion circuit, in particular to a high-level energy-taking voltage conversion circuit.

Background technique

At present, there are mainly two types of energy supply methods for different converter valve drive boards: low-pressure energy delivery and high-pressure energy acquisition.

The most widely used method for low-voltage energy transmission is the electromagnetic energy transmission method that sends the energy of the ground potential to the driver board on the high-voltage side through a high-frequency pulse transformer. This method requires high-reliability voltage isolation measures, and there are external insulation and structural installation and other issues, so the volume and cost of the equipment are very large, generally used in relatively low voltage occasions.

For high-voltage energy harvesting, it is common to use a special current transformer (CT) to induce voltage from the line, and provide it to the driver board after processing. The characteristic is that the energy can only be obtained when there is current flowing in the line when the switching device is turned on. This method is often used in series valves where thyristors are switching devices, because thyristors are semi-controlled devices that do not require shutdown energy. However, for fully-controlled switching devices that require energy both to be turned on and off, it is difficult to meet the high-power energy supply requirements of the power module in this way.

Another common form of high-voltage energy harvesting is to supply energy to the drive through the resistance-capacitance elements connected in parallel of the switching device combined with a certain energy harvesting unit circuit. This energy harvesting device is used to charge the energy harvesting capacitor when the voltage at both ends of the switching device rises, until the charging meets the requirements. It is mainly used in series valves where thyristors are switching devices. For high-frequency switching devices, the turn-off process is relatively short. If this energy harvesting method is used, it will take many cycles to obtain the required energy, which cannot meet the continuous high-power energy supply requirements of the power module.

The conventional switching power supply seen so far has not been reported to be applied to high-potential energy harvesting. Its input voltage is usually 220V AC, 380V AC or DC voltage within 100V, which cannot meet the high-voltage requirements of high-voltage and high-power modules. In addition, the input voltage range of a conventional switching power supply is up to three times, which cannot meet the wide-range voltage input requirements of the power module energy harvesting power supply.

Contents of the invention

The object of the present invention is to provide a high-level energy-taking voltage conversion circuit for high-voltage and high-power modules that takes energy from high potential and realizes wide-range voltage input.

Object of the present invention adopts following technical scheme to realize:

A high-level energy-taking voltage conversion circuit, the improvement of which is that the circuit is composed of three-phase six bridge arms, and the upper and lower bridge arms are connected by bridge arm reactors; each bridge arm is composed of a high-voltage power module stage The high-voltage power module includes a high-voltage module, a capacitor and a high-level energy-taking device; the high-voltage module, capacitor and high-level energy-taking device are connected in parallel in sequence.

A preferred technical solution provided by the present invention is: the high-voltage module includes an IGBT controller, a fully-controlled power electronic device IGBT, a diode D, protection equipment, and control equipment; the IGBT controller includes an IGBT1 controller and an IGBT2 controller The fully controlled power electronic device IGBT includes IGBT1 and IGBT2; the diode D includes D3 and D4.

The second preferred technical solution provided by the present invention is: the anti-parallel connection of the IGBT1 and the diode D3 forms the turn-off thyristor G1; the anti-parallel connection of the IGBT2 and the diode D4 forms the turn-off thyristor G2; the control device, the IGBT1 controller connected in series with the turn-off thyristor G1; the protection device, the IGBT2 controller and the turn-off thyristor G2 are connected in series; the control device is connected in series with the protection device; the IGBT1 controller is connected in parallel with the IGBT2 controller; The turn-off thyristor G1 and the turn-off thyristor G2 are connected in series.

The third preferred technical solution provided by the present invention is: the high-level energy-taking device includes a buffer absorbing circuit and a switching power supply circuit; the buffer absorbing circuit includes a resistor R1, a capacitor C2, and a diode D2; the resistor R1 and capacitor C2 are connected in parallel and diode D2 in series; the switching power supply circuit includes a transformer T1, an inductor L _LT , a diode D1, a capacitor C1, a control chip and a MOS tube Tr; the primary winding of the transformer T1 is connected in series with the inductor L _LT ; the transformer T1 The secondary winding, the diode D2 and the capacitor C1 are connected in series; the control chip is connected to the gate of the MOS transistor Tr; the drain of the MOS transistor Tr is respectively connected to the anode of the inductance L _LT and the snubber circuit diode D2.

The fourth preferred technical solution provided by the present invention is: the high-level energy-taking device is called a voltage conversion circuit, and the voltage conversion circuit adopts a single-transistor flyback structure.

Compared with prior art, the beneficial effect that the present invention reaches is:

1. The high-level energy-taking voltage conversion circuit provided by the present invention obtains energy from the high-potential of the power module, which avoids high-strength insulation design and simplifies the structure of the application system;

2. The high-level energy-taking voltage conversion circuit provided by the present invention uses a high-voltage MOS tube to realize direct conversion of high input voltage, and has a simple structure and convenient control;

3. The high-level energy-taking voltage conversion circuit provided by the present invention adopts a single-tube flyback topology topology, with a wide range of voltage input and high input impedance;

4. The high-level energy-acquiring voltage conversion circuit provided by the present invention can continuously obtain energy and realize continuous high-power stable power supply.

Description of drawings

Fig. 1 is the schematic diagram of the conversion circuit of the high-level energy-taking circuit;

Fig. 2 is a schematic diagram of a high-voltage power module circuit;

Fig. 3 is a schematic diagram of a high-level energy harvesting device.

Detailed ways

The specific embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Figure 1 is a schematic diagram of the conversion circuit of the high-level energy-taking circuit; the circuit is composed of three-phase six bridge arms, and the upper and lower bridge arms of each phase are connected by bridge arm reactors; each bridge arm is composed of several high-voltage power modules connected in cascade. The high-voltage power module includes a high-voltage module, a capacitor and a high-level energy-taking device; the high-voltage module, a capacitor and a high-level energy-taking device are connected in parallel in sequence.

Figure 2 is a schematic diagram of a high-voltage power module circuit; where the high-voltage module includes an IGBT controller, a fully-controlled power electronic device IGBT, a diode D, protection equipment, and control equipment; the IGBT controller includes an IGBT1 controller and an IGBT2 controller; The controlled power electronic device IGBT includes IGBT1 and IGBT2; the diode D includes D3 and D4; the anti-parallel connection of IGBT1 and diode D3 forms the turn-off thyristor G1; the anti-parallel connection of IGBT2 and diode D4 forms the turn-off thyristor G2; control equipment, IGBT1 controller and the turn-off thyristor G1 in series; the protection equipment, the IGBT2 controller and the turn-off thyristor G2 are connected in series; the control equipment is connected in series with the protection equipment; the IGBT1 controller is connected in parallel with the IGBT2 controller; the turn-off thyristor G1 and the turn-off thyristor The disconnected thyristor G2 is connected in series. The input voltage of the high-level energy-taking voltage conversion circuit provided by the present invention is the DC side voltage of the high-voltage power module. The high-voltage power module uses a large capacitor to provide a stable DC working voltage on the DC side during operation, providing a stable voltage for the high-voltage power module. Energy harvesting points.

Figure 3 is a schematic diagram of high-level energy harvesting equipment; the high-level energy harvesting device includes a buffer absorption circuit and a switching power supply circuit; the buffer absorption circuit includes a resistor R1, a capacitor C2, and a diode D2; the resistor R1 and capacitor C2 are connected in parallel and connected in series with the diode D2; the switch The power circuit includes transformer T1, inductor L _LT , diode D1, capacitor C1, control chip and MOS tube Tr; the primary winding of transformer T1 is connected in series with inductor L _LT ; the secondary winding of transformer T1, diode D2 and capacitor C1 are connected in series; the control The chip is connected to the gate of the MOS transistor Tr; the drain of the MOS transistor Tr is respectively connected to the anode of the inductance L _LT and the buffer absorption circuit diode D2; the high-level energy-taking device is called a voltage conversion circuit, and the single-transistor flyback used in the voltage conversion circuit formula structure. As shown in Figure 3, the positive and negative poles of the wide-range high-voltage input are respectively connected to the positive and negative poles of the branch where the high-level energy harvesting device is located in Figure 2.

The voltage conversion circuit adopts a single-tube flyback topology with the advantages of simple structure and convenient control, which completes the conversion of high voltage into low voltage. The switching device of the voltage conversion circuit uses a high-voltage MOS tube to achieve high voltage conversion; The circuit absorbs the flyback surge voltage and increases the reliability of the circuit; the voltage conversion circuit needs to work reliably and stably within the wide voltage input range from 250V to 2500V. During the working process, the DC side capacitance of the high voltage power module is between 250V and Fluctuates between 2500V and accompanied by ripple voltage, the voltage conversion circuit converts the output voltage to 15V and keeps it stable when the input voltage fluctuates.

Finally, it should be noted that: the combination of the above embodiments only illustrates the technical solution of the present invention rather than limiting it. Those of ordinary skill in the art should understand that: those skilled in the art can make modifications or equivalent replacements to the specific embodiments of the present invention, but these modifications or changes are all within the protection scope of the pending claims.

Claims (1)

1. a high-order energy gaining voltage conversion circuit, is characterized in that, described circuit is made up of three-phase six brachium pontis, and upper and lower bridge arm is coupled together by brachium pontis reactor; Each brachium pontis is formed by high-voltage power module-cascade; Described high-voltage power module comprises high-pressure modular, electric capacity and a high position and gets energy equipment; It is in parallel successively that described high-pressure modular, electric capacity and a high position get energy equipment;

Described high-pressure modular comprises IGBT controller, all-controlling power electronics device IGBT, diode D, proterctive equipment and control appliance; Described IGBT controller comprises IGBT1 controller and IGBT2 controller; Described all-controlling power electronics device IGBT comprises IGBT1 and IGBT2; Described diode D comprises D3 and D4;

Described IGBT1 and diode D3 inverse parallel composition turn-off thyristor G1; Described IGBT2 and diode D4 inverse parallel composition turn-off thyristor G2; Described control appliance, IGBT1 controller and turn-off thyristor G1 connect successively; Described proterctive equipment, IGBT2 controller and turn-off thyristor G2 are connected in series; Described control appliance is connected with described proterctive equipment; Described IGBT1 controller is in parallel with IGBT2 controller; Described turn-off thyristor G1 and turn-off thyristor G2 connects;

A described high position is got and can be comprised snubber circuit and switching power circuit by equipment; Described snubber circuit comprises resistance R1, electric capacity C2 and diode D2; Connect with diode D2 after described resistance R1 and electric capacity C2 parallel connection; Described switching power circuit comprises transformer T1, inductance L _lT, diode D1, electric capacity C1, control chip and metal-oxide-semiconductor Tr; A winding of described transformer T1 and inductance L _lTseries connection; Secondary winding, the diode D2 and electric capacity C1 of described transformer T1 are connected in series; Described control chip is connected with the grid of metal-oxide-semiconductor Tr; The drain electrode of described metal-oxide-semiconductor Tr respectively with inductance L _lTbe connected with the positive pole of snubber circuit diode D2;

A described high position is got and can be called voltage conversion circuit by equipment, the single switch flyback formula structure that described voltage conversion circuit adopts;

Voltage conversion circuit adopts single switch flyback formula topological structure, and it completes and converts high voltage to low-voltage, and voltage conversion circuit switching device adopts high-voltage MOS pipe to realize high-tension conversion; Voltage conversion circuit adopts snubber circuit, absorbs flyback surge voltage, increases circuit working reliability; Voltage conversion circuit needs from reliable and stable work within the scope of the Width funtion input service of 250V ~ 2500V, in the course of the work, the DC bus capacitor of high-voltage power module fluctuates between 250V ~ 2500V, and with ripple voltage, voltage conversion circuit is when input voltage fluctuation, the voltage 15V that conversion exports, keeps stable.