CN-115566643-B - Modularized parallel power supply direct current input side short circuit cooperative protection circuit

Abstract

The invention discloses a modularized parallel power supply direct current input side short circuit cooperative protection circuit which is divided into two stages, wherein a first stage protection circuit is a direct current bus input side explosion bridge, a second stage protection circuit comprises a fuse, a thyristor, a resistor, a capacitor and a contactor, the positive electrode of a common direct current bus is connected with the first end of the fuse, the second end of the fuse is connected with the first end of the resistor and the positive electrode of the thyristor, the second end of the resistor and the negative electrode of the thyristor are connected with the capacitor and the positive electrode of a module, the negative electrode of the common direct current bus is connected with the first end of the contactor, and the second end of the contactor is connected with the capacitor and the negative electrode of the module. Each power module is independently provided with a group of second-stage protection circuits. By adopting two-stage protection, the cooperation of short-circuit protection of the device and other devices sharing the bus, the cooperation of short-circuit protection of the whole device and internal modules and the cooperation of short-circuit protection among the modules can be realized, and the circuit is simple and the application range is wide.

Inventors

• JIN XIANG
• LI KEWEI
• WU FANG
• WEI HUA
• CHEN TAO
• LUO WEI
• Geng pan
• LI RUI
• WU HAOWEI
• CHEN JING
• LI PENG
• SUN HAIJING
• CAI KAI
• CAI JIUQING
• KONG XIANGWEI

Assignees

• 中国船舶重工集团公司第七一九研究所

Dates

Publication Date

20260505

Application Date

20220913

Claims (3)

1. 1. A modularized parallel power supply direct current input side short circuit cooperative protection circuit is characterized by comprising two stages, wherein a first stage protection circuit is a direct current bus input side explosion bridge, a second stage protection circuit comprises a fuse FCi, a thyristor Ti, a resistor Ri, a capacitor Ci and a contactor Si, the positive electrode of a common direct current bus is connected with the first end of the fuse FCi, the second end of the fuse FCi is connected with the first end of the resistor Ri and the anode of the thyristor Ti, the second end of the resistor Ri and the cathode of the thyristor Ti are connected with the capacitor Ci and the anode of a power module i, the negative electrode of the common direct current bus is connected with the first end of the contactor Si, the second end of the contactor Si is connected with the capacitor Ci and the cathode of the power module i, the action time of the fuse FCi is shorter than the action time of the thyristor Ti and the explosion bridge, and i E1, 2, 3.
2. 2. The short-circuit cooperative protection circuit of claim 1, wherein a set of the second stage protection circuits is independently configured for each power module in a modular parallel power supply.
3. 3. The circuit according to claim 1, wherein the bypass capacitor Ci is powered slowly through the resistor Ri and the thyristor Ti, and the non-short-circuit fault power modules are isolated through the contactors Si, and each contactor is independently controlled by a corresponding power module.

Description

Modularized parallel power supply direct current input side short circuit cooperative protection circuit Technical Field The invention relates to the technical field of power supplies, in particular to a direct current input side short circuit cooperative protection circuit of a modularized parallel power supply. Background The modularized parallel power supply is formed by combining a plurality of power modules in parallel on an input side and an output side. The combination mode of parallel connection of the input side and the output side can improve the reliability of power supply of a power supply, reduce the current stress requirement on a switching device of the converter, flexibly and conveniently expand the capacity, and has remarkable advantages in high-capacity power conversion application occasions. The power supply device adopts a modularized parallel design scheme, has higher requirements on the synergy of the short-circuit protection of the direct-current input side, and is particularly characterized in that the synergy of the short-circuit protection of the device and other devices of the common direct-current bus, the synergy of the short-circuit protection of the whole device and the internal power module and the synergy of the short-circuit protection among the power modules are required to be realized. Fig. 1 shows a circuit block diagram of a direct current input end of a modularized parallel power supply, wherein the direct current input end can be divided into 4 sections, namely a direct current bus section 1, a whole machine input side element section 2, a branch input side element section 3 and a power module input side section 4. The short-circuit protection targets of each segment are as follows: the first section short circuit protection target is that when a public direct current bus is short-circuited, the whole explosion bridge is required not to be protected, the device can realize fault ride-through, and the specific requirement is that the direct current capacitors in sections 2, 3 and 4 are not discharged through bus short-circuit points or the discharge current is insufficient to trigger the explosion bridge to act; the second section of short circuit protection target is that when the input side element of the whole machine is short-circuited, the explosion bridge of the whole machine realizes protection action and requires the branch circuit protection circuits of all modules to be not operated; The third short-circuit protection target is that when a short circuit occurs at the input side of a certain branch, the branch fault is required to be quickly cut off, so that the whole explosion bridge does not act, and capacitors in other branches or modules are required to be incapable of discharging the short-circuit point, or the discharging current is insufficient to cause the protection action of other branches or the voltage drop of the capacitors; and the fourth short-circuit protection target is the same as the third short-circuit protection target. As shown in fig. 2, a typical dc input side circuit of a modular parallel power supply is provided, and all power modules share a set of circuits, where the circuits include resistors, a slow power-up switch, and a bus supporting capacitor, and the slow power-up switch is usually a contactor or a thyristor. The circuit has a simple structure, can realize slow power-up of the bus support capacitor, but cannot realize the cooperative protection of the whole machine short circuit described above in connection with fig. 1, but can reduce the power supply reliability of the whole device, and the advantage of the modularized parallel power supply is lost. Disclosure of Invention The invention aims to overcome the defects of the prior art, and provides a modularized parallel power supply direct current input side short circuit cooperative protection circuit, by adopting the circuit scheme, the device and other devices sharing the bus can realize the cooperation of short-circuit protection, the cooperation of the short-circuit protection of the whole device and the internal power module and the cooperation of the short-circuit protection between the power modules, and the reliability of the power supply of the whole device is greatly improved. The invention provides a modularized parallel power supply direct current input side short circuit cooperative protection circuit which is divided into two stages, wherein the first stage protection circuit is a direct current bus input side explosion bridge, the second stage protection circuit comprises a fuse FCi, a thyristor Ti, a resistor Ri, a capacitor Ci and a contactor Si, the positive electrode of a common direct current bus is connected with the first end of the fuse FCi, the second end of the fuse FCi is connected with the first end of the resistor Ri and the anode of the thyristor Ti, the second end of the resistor Ri and the cathode of the thyristor Ti are connected with the capa