DC short circuit breaker based on super capacitor

Abstract

The utility model relates to the technical field of circuit breakers, in particular to a direct current short circuit breaker based on a super capacitor. The system comprises a bus module, a circuit break control module and a branch module, the bus module comprises a rectification circuit and a bus air switch, the circuit break control module comprises a charging circuit and a discharging circuit, the branch module comprises a plurality of branch air switches, and the circuit break control module is connected with the bus module in parallel and is connected with the branch module. According to the utility model, the bus module converts an alternating current into a direct current through the rectification circuit, transmits the direct current to the circuit break control module, stores the direct current in the super capacitor through the charging circuit, and when a short circuit occurs in the branch module, the super capacitor starts current-unlimited discharge through the discharging circuit and instantly opens a branch air switch. The whole line is protected.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit breakers, and specifically, to a DC short-circuit circuit breaker based on a super capacitor. Background Technique

[0002] A DC short-circuit circuit breaker is a protection device used in DC circuits. It can quickly cut off the circuit when detecting faults such as overload and short circuit, thereby protecting the equipment and personnel safety in the circuit. The DC short-circuit circuit breaker controls the on-off of the circuit by detecting the magnitude of the current. When the current exceeds the preset value, the circuit breaker will quickly open to cut off the circuit.

[0003] At present, the design and manufacturing costs of existing DC circuit breakers on the market are relatively high, and their sizes are relatively large, which limits their use in some application scenarios. In addition, when some DC circuit breakers encounter short circuits, their response times are too slow, resulting in damage to components in the system. Therefore, we propose a DC short-circuit circuit breaker based on a super capacitor. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a DC short-circuit circuit breaker based on a super capacitor to solve the problems raised in the above background technique.

[0005] To achieve the above purpose, the utility model provides a DC short-circuit circuit breaker based on a super capacitor, which includes a busbar module, a breaking control module, and a branch module. The busbar module includes a rectification circuit and a busbar air switch. The breaking control module includes a charging circuit and a discharging circuit. The branch module includes a plurality of branch air switches. The breaking control module is connected in parallel with the busbar module and connected to the branch module;

[0006] The busbar module converts alternating current into direct current through the rectification circuit and transmits the direct current to the breaking control module. The direct current is stored in the super capacitor through the charging circuit. When a short circuit occurs in the branch module, the super capacitor starts unrestricted current discharge through the discharging circuit, instantly opening the branch air switch to protect the entire line.

[0007] As a further improvement of this technical solution, the busbar module includes a rectification circuit and a busbar air switch. The rectification circuit includes a transformer T1 and a rectifier bridge BG1 connected to the secondary winding of the transformer T1, where:

[0008] The primary winding of the transformer T1 is connected to alternating current. One end of the rectifier bridge BG is connected to a resistor R1 and is connected in parallel with a capacitor C1. The other end of the rectifier bridge BG1 is connected to the positive pole of a voltage stabilizing diode VD, and a capacitor C2 is connected in parallel with the other end of the capacitor C1. The resistor R5 is connected to the negative pole of the voltage stabilizing diode VD and is connected to the other end of the capacitor C2.

[0009] As a further improvement of the technical solution, the open - circuit control module includes a charging circuit, and the charging circuit includes resistors R2, R3 and supercapacitors C3, C4, C5 and C6, where:

[0010] One end of the resistor R2 is connected in series with one end of the resistor R3, the other end of the resistor R3 is connected in parallel with one ends of the supercapacitors C3, C4, C5 and C6, and the other ends of the supercapacitors C3, C4, C5 and C6 and the other end of the resistor R2 are connected to the busbar.

[0011] As a further improvement of the technical solution, the open - circuit control module includes a discharging circuit, and the discharging circuit includes rectifier bridges BG2, BG3, BG4, BG5 and supercapacitors C3, C4, C5 and C6, where:

[0012] Each of the rectifier bridges BG2, BG3, BG4 and BG5 is composed of four diodes, where: the positive pole of diode D1 is connected in series with the negative pole of diode D2, the positive pole of diode D4 is connected in series with the negative pole of diode D3, and the negative pole of diode D1 and the positive pole of diode D2 are connected in parallel with the negative pole of diode D4 and the positive pole of diode D3;

[0013] Both ends of the rectifier bridge BG2 are connected in series with the supercapacitor C3 and then connected to the busbar in parallel. Similarly, the rectifier bridges BG3, BG4 and BG5 are connected in series with the supercapacitors C4, C5 and C6 and then connected to the busbar in parallel.

[0014] As a further improvement of the technical solution, both the resistors R2 and R3 of the charging circuit are cement resistors.

[0015] As a further improvement of the technical solution, the time constants of the supercapacitors C3, C4, C5 and C6 are all 0.408S.

[0016] Compared with the prior art, the beneficial effects of the present utility model are:

[0017] For this DC short - circuit breaker based on supercapacitors, the rectifying circuit of the busbar module converts alternating current into direct current and transmits it to the DC busbar. This device is connected in parallel to the DC busbar, and the DC busbar sends the direct current to the supercapacitors for storage through the current - limiting of the cement resistors R2 and R3. When a short - circuit occurs on the load of the system branch, the supercapacitors start to discharge without current - limiting to the short - circuit fault point through the rectifier bridge. Its response time is in the millisecond level, and it can instantly open the branch air switch on the faulty branch. The DC output will not trigger a short - circuit rollback within the response time of this device, so the busbar air switch will not trip due to the branch fault, effectively ensuring the stability of the DC busbar voltage. The opened branch air switch can isolate the faulty branch, preventing potential safety hazards caused by the faulty branch when the system module is powered on again, and protecting the system. Brief Description of the Drawings

[0018] Figure 1 This is the overall structural schematic diagram of the present utility model 1;

[0019] Figure 2 This is the rectifier circuit structural schematic diagram of the present utility model 1;

[0020] Figure 3 This is the circuit principle schematic diagram of the present utility model 1. Detailed Description of the Preferred Embodiments

[0021] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0022] Please refer to Figures 1 - 3 As shown, the present utility model provides a DC short - circuit breaker based on a supercapacitor, including a bus bar module, a breaking control module, and a branch module. The bus bar module includes a rectifier circuit and a bus bar air switch. The breaking control module includes a charging circuit and a discharging circuit. The branch module includes a plurality of branch air switches. The breaking control module is connected in parallel with the bus bar module and connected to the branch module;

[0023] The bus bar module converts alternating current into direct current through the rectifier circuit and transmits the direct current to the breaking control module. The direct current is stored in the supercapacitor through the charging circuit. When a short - circuit occurs in the branch module, the supercapacitor starts unrestricted - current discharging through the discharging circuit, instantly tripping the branch air switch to protect the entire line.

[0024] Principle: The rectifier circuit of the bus bar module converts alternating current into direct current and transmits it to the DC bus bar. This device is connected in parallel to the DC bus bar. The DC bus bar limits the current through cement resistors R2 and R3 and transmits the direct current to the supercapacitor for storage. When a short - circuit occurs on the system branch load, the supercapacitor starts unrestricted - current discharging to the short - circuit fault point through the rectifier bridge. Its response time is in the millisecond level, and it can instantly trip the branch air switch on the faulty branch. The DC output will not trigger short - circuit re - winding within the response time of this device, so the bus bar air switch will not trip due to the branch fault, effectively ensuring the stability of the DC bus bar voltage. The tripped branch air switch can isolate the faulty branch, preventing potential safety hazards caused by the faulty branch when the system module is powered on again, and protecting the system.

[0025] In order to charge the supercapacitor after converting external alternating current into direct current, among which,

[0026] The busbar module includes a rectifying circuit and a busbar air switch. The rectifying circuit includes a transformer T1 and a rectifier bridge BG1 connected to the secondary winding of the transformer T1, where:

[0027] The primary winding of the transformer T1 is connected to alternating current. One end of the rectifier bridge BG is connected to a resistor R1 and a capacitor C1 in parallel. The other end of the rectifier bridge BG1 is connected to the positive pole of a zener diode VD, a capacitor C2, and the other end of the capacitor C1 in parallel. The resistor R5 is connected to the negative pole of the zener diode VD and the other end of the capacitor C2.

[0028] This circuit converts alternating current into pulsating direct current through the rectifier bridge BG1, and performs smoothing filtering through capacitors C1 and C2. Then, the zener diode VD realizes the output of constant-voltage direct current. The direct current output will not trigger a short-circuit rollback within the response time of the device, so the busbar air switch will not trip due to a branch fault, effectively ensuring the stability of the DC bus voltage. The tripped branch air switch can isolate the faulty branch and prevent potential safety hazards caused by the faulty branch when the system is powered on again.

[0029] In order to safely store direct current in supercapacitors C3, C4, C5, and C6, where

[0030] The open-circuit control module includes a charging circuit. The charging circuit includes resistors R2, R3, and supercapacitors C3, C4, C5, and C6, where:

[0031] One end of the resistor R2 is connected in series with one end of the resistor R3. The other end of the resistor R3 is connected in parallel with one end of the supercapacitors C3, C4, C5, and C6. The other ends of the supercapacitors C3, C4, C5, and C6 are connected in parallel with the other end of the resistor R2 to the busbar.

[0032] In this circuit, the direct current is divided by the resistors R2 and R3 to supply current to the supercapacitors C3, C4, C5, and C6 in a current-limiting manner, thus ensuring the normal charging of the supercapacitors C3, C4, C5, and C6.

[0033] In order to ensure that the supercapacitors C3, C4, C5, and C6 can discharge quickly when a short circuit occurs in the branch module, where

[0034] The open-circuit control module includes a discharging circuit. The discharging circuit includes rectifier bridges BG2, BG3, BG4, BG5, and supercapacitors C3, C4, C5, and C6, where:

[0035] The rectifier bridges BG2, BG3, BG4, and BG5 are each composed of four diodes, where: the positive pole of diode D1 is connected in series with the negative pole of diode D2, the positive pole of diode D4 is connected in series with the negative pole of diode D3, and the negative pole of diode D1 and the positive pole of diode D2 are connected in parallel with the negative pole of diode D4 and the positive pole of diode D3;

[0036] Both ends of the rectifier bridge BG2 are connected in series with the super capacitor C3 and then connected in parallel to the bus. Similarly, the rectifier bridges BG3, BG4 and BG5 are connected in series with the super capacitors C4, C5 and C6 and then connected in parallel to the bus.

[0037] In this circuit, when a short circuit occurs in the branch module, the voltage on the system bus drops. At this time, the voltages of the super capacitors C3, C4, C5 and C6 are higher than the bus voltage, resulting in the voltages of the super capacitors C3, C4, C5 and C6 gradually approaching the bus voltage. At this time, the super capacitors C3, C4, C5 and C6 start unrestricted current discharge through the rectifier bridges BG2, BG3, BG4 and BG5. The released current opens the nearest branch air switch, and the opened branch air switch can isolate the faulty branch to prevent potential safety hazards caused by the faulty branch when the system is powered on again.

[0038] In order to enable this device to adapt to occasions with large currents, among them, the resistors R2 and R3 of the charging circuit both use cement resistors. Cement resistors are resistors with relatively large power and can allow large currents to pass through. The direct current is divided and current-limited through the cement resistors R2 and R3 to protect the super capacitors C3, C4, C5 and C6, greatly improving the practicality of this device.

[0039] In order to enable this device to respond quickly when the system is short-circuited, among them, the time constants τ of the super capacitors C3, C4, C5 and C6 are all 0.408S. After about 3τ, that is, 1.2S, it can reach the input state of 95% voltage. After about 5τ, that is, 2S, it can be fully charged and put into use, so as to ensure that the super capacitors C3, C4, C5 and C6 are in a fully charged state. When a short circuit occurs in the branch module, this device can respond quickly to protect the entire line.

[0040] This DC short-circuit breaker based on super capacitors converts alternating current into direct current through the rectifier circuit of the bus module and transmits it to the DC bus. This device is connected in parallel to the DC bus. The DC bus transmits the direct current through the cement resistors R2 and R3 for current limiting and stores it in the super capacitor. Cement resistors are resistors with relatively large power and can allow large currents to pass through. The direct current is divided and current-limited through the cement resistors R2 and R3 to protect the super capacitors C3, C4, C5 and C6, greatly improving the practicality of this device. When a short circuit occurs in the system branch load, the super capacitor starts unrestricted current discharge towards the short-circuit fault point through the rectifier bridge. Its response time is in the millisecond level and can instantly open the branch air switch on the faulty branch. The DC output will not trigger short-circuit rewind within the response time of this device, so that the bus air switch will not trip due to branch faults, effectively ensuring the stability of the DC bus voltage. The opened branch air switch can isolate the faulty branch to prevent potential safety hazards caused by the faulty branch when the system module is powered on again, protecting the system.

[0041] The above has shown and described the basic principles, main features and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present utility model and are not used to limit the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A DC short-circuit breaker based on supercapacitor, characterized in that: It includes a bus module, a circuit breaker control module and a branch module, wherein the bus module includes a rectifier circuit and a bus circuit breaker, the circuit breaker control module includes a charging circuit and a discharging circuit, the branch module includes a plurality of branch circuit breakers, and the circuit breaker control module is connected in parallel to the bus module and the branch module; The bus module converts AC power into DC power through a rectifier circuit, transmits DC power to the circuit breaker control module, and stores DC power in a supercapacitor through a charging circuit. When a short circuit occurs in the branch module, the supercapacitor begins to discharge without current limit through a discharge circuit, instantly flushing the branch breaker to protect the entire line.

2. The DC short circuit breaker based on supercapacitor according to claim 1, characterized in that: The bus module includes a rectifier circuit and a bus circuit breaker. The rectifier circuit includes a transformer T1 and a rectifier bridge BG1 connected to the secondary winding of the transformer T1, wherein: The main winding of the transformer T1 is connected to AC power, one end of the rectifier bridge BG is connected to the resistor R1 and connected to the capacitor C1, the other end of the rectifier bridge BG1 is connected to the positive electrode of the Zener diode VD and the capacitor C2 and connected to the other end of the capacitor C1, and the resistor R5 is connected to the negative electrode of the Zener diode VD and connected to the other end of the capacitor C2.

3. The DC short circuit breaker based on supercapacitor according to claim 1, characterized in that: The circuit breaker control module includes a charging circuit, which includes resistors R2, R3 and supercapacitors C3, C4, C5 and C6, wherein: One end of the resistor R2 is connected in series with one end of the resistor R3, the other end of the resistor R3 is connected in parallel with one end of the supercapacitors C3, C4, C5 and C6, and the other ends of the supercapacitors C3, C4, C5 and C6 are connected in parallel with the other end of the resistor R2 on the bus.

4. The DC short circuit breaker based on supercapacitor according to claim 1, characterized in that: The circuit breaker control module includes a discharge circuit, which includes rectifier bridges BG2, BG3, BG4, BG5 and supercapacitors C3, C4, C5 and C6, wherein: The rectifier bridges BG2, BG3, BG4 and BG5 are each composed of four diodes, wherein: the anode of the diode D1 is connected in series with the cathode of the diode D2, the anode of the diode D4 is connected in series with the cathode of the diode D3, and the cathode of the diode D1 and the anode of the diode D2 are connected in parallel with the cathode of the diode D4 and the anode of the diode D3; The two ends of the rectifier bridge BG2 are connected in series with the super capacitor C3 and then connected to the busbar. Similarly, the rectifier bridges BG3, BG4 and BG5 are connected in series with the super capacitors C4, C5 and C6 and then connected to the busbar.

5. The DC short circuit breaker based on supercapacitor according to claim 1, characterized in that: The resistors R2 and R3 of the charging circuit are both cement resistors.

6. The DC short circuit breaker based on supercapacitor according to claim 1, characterized in that: The time constant τ of the supercapacitors C3, C4, C5 and C6 is 0.408S.

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