CN210201483U

CN210201483U - DC bus protector for converter

Info

Publication number: CN210201483U
Application number: CN201921502297.6U
Authority: CN
Inventors: Xianqiao Yu; 俞贤桥; Shiyong Jiang; 蒋世用; Wu Wen; 文武; Ningning Chen; 陈宁宁; Dongrui Qu; 曲东瑞
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2019-09-10
Filing date: 2019-09-10
Publication date: 2020-03-27
Anticipated expiration: 2029-09-10

Abstract

The utility model discloses a converter direct current bus protection device, it includes: the protection circuit comprises a switching module and a plurality of protection circuits with different functions, wherein the protection circuits are used for being connected between a direct current bus and a direct current load, and the switching module is used for switching the protection circuits connected between the direct current bus and the direct current load. Adopt the technical scheme of the utility model, can form the protection of multiple functions to the direct current generating line of converter.

Description

DC bus protector for converter

Technical Field

The utility model relates to a converter field especially relates to a converter direct current bus protection device.

Background

With the development of new energy industry, the converter or the converter unit plays a significant role as a basic energy conversion part. The converter generally consists of basic topologies such as DC/DC, AC/DC or DC/AC, wherein the DC voltage is the DC bus voltage, and is usually tens of volts to hundreds of volts.

The dc bus may have the following fault problems: 1. the problems of bus capacitor explosion and direct current load damage on the direct current bus caused by the reverse connection of the polarity of the direct current bus; 2. the problem of slow discharge of residual charges of a bus capacitor on the direct current bus is solved; 3. the direct current load is adjusted slowly in real time, and the direct current load can be adjusted only after the power supply of the system is cut off; 4. and short circuit caused by self fault of the direct current load causes short circuit of the direct current bus.

If the direct current bus is not properly protected, the function of the converter can be failed, and even the normal operation of the whole system is affected.

SUMMERY OF THE UTILITY MODEL

The utility model aims at the technical problem among the above-mentioned prior art, provide a can effectively protect converter direct current bus protection device of direct current bus of converter.

The embodiment of the utility model provides an in, a converter direct current bus protection device is provided, its protection circuit including switching module and a plurality of different functions, a plurality of protection circuit are used for connecting between direct current bus and direct current load, the switching module is used for switching the protection circuit of connecting between direct current bus and direct current load.

The embodiment of the utility model provides an in, protection circuit is including being used for respectively with the positive link of direct current generating line, negative pole link, the positive link of direct current load, first link, second link, third link and the fourth link that negative pole link is connected, switching module is used for control four links of protection circuit are connected and are disconnected with the positive link of direct current generating line, negative pole link, the positive link of direct current load, negative pole link.

In the embodiment of the utility model provides an in, switch over the module including being used for bearing a plurality of protection circuit's rotary part works as when rotary part rotated the angle of settlement, four connecting terminal of protection circuit just are connected with positive link, negative pole link, the positive link of direct current load, negative pole link of direct current generating line.

In the embodiment of the utility model, switch the module and still include drive circuit, step motor and pivot, the pivot with rotary part is connected, step motor with the pivot is connected, drive circuit with step motor connects, drive circuit is used for sending drive signal, drive step motor is rotatory, and drives rotary part rotates.

In the embodiment of the utility model, four links of protection circuit set up in with the pivot is on four angles of the square at center.

In the embodiment of the present invention, the protection circuits include a polarity reversal protection circuit and a residual charge discharging circuit.

In the embodiment of the utility model provides an, polarity reversal protection circuit includes diode D1, D2, D3, D4, polarity reversal protection circuit's first link is connected with diode D1's positive pole and diode D3's negative pole respectively, polarity reversal protection circuit's second link is connected with diode D1's negative pole and diode D4's negative pole respectively, polarity reversal protection circuit's third link is connected with diode D2's positive pole and diode D3's positive pole respectively, polarity reversal protection circuit's fourth link is connected with diode D2's negative pole and diode D4's positive pole respectively.

In the embodiment of the utility model provides an in, polarity reversal protection circuit still includes fuse FU1, FU2, fuse FU1 connect in diode D1's negative pole with between polarity reversal protection circuit's the second link, fuse FU2 connect in diode D4 the positive pole with between polarity reversal protection circuit's the fourth link.

In the embodiment of the present invention, the residual charge discharging circuit includes resistors R1, R2, R3, R4, resistors R1, R2 are connected in series between the second connecting end and the third connecting end of the residual charge discharging circuit, and resistors R3, R4 are connected in series between the first connecting end and the fourth connecting end of the residual charge discharging circuit.

The embodiment of the utility model provides an in, still include with the control module that the switching module is connected, control module is used for transmitting user's switching instruction for the switching module.

Compared with the prior art, in the converter direct current bus protection device of the utility model, the switching module is used for switching the protection circuit connected between the direct current bus and the direct current load, so that various different protection functions can be provided for the direct current bus according to the actual requirement; through with four link settings of a plurality of protection circuit can be rotatory on rotary part, can be through the rotation the access and the disconnection of multiple protection circuit are realized to rotary part's mode to realize different protect function, the switching process is simple, easily realizes.

Drawings

Fig. 1 is a schematic structural diagram of a converter dc bus protection device according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a switching module according to an embodiment of the present invention.

Fig. 3 is a schematic diagram of a normal working state of the dc bus protection device of the embodiment of the present invention.

Fig. 4 is a schematic diagram of an operating state of the converter dc bus protection device according to the embodiment of the present invention, which realizes the reverse connection prevention function.

Fig. 5 is a schematic diagram of an operating state of the converter dc bus protection device according to the embodiment of the present invention for realizing the adjustment of the instant dc load.

Fig. 6 is a schematic view of an operating state of the converter dc bus protection device according to the embodiment of the present invention, in which the converter dc bus protection device realizes rapid charge discharge.

Detailed Description

As shown in fig. 1, an embodiment of the present invention provides a converter dc bus protection device, which includes a control module, a switching module, a polarity reversal protection circuit and a residual charge discharging circuit. The polarity reversal protection circuit and the residual charge discharge circuit are respectively used for being connected between a direct current bus and a direct current load so as to protect the direct current bus, the switching module is used for switching the polarity reversal protection circuit and the residual charge discharge circuit which are connected between the direct current bus and the direct current load, and the control module is used for transmitting a switching instruction of a user to the switching module.

The polarity reverse connection protection circuit comprises diodes D1, D2, D3 and D4, and a first connection end 1, a second connection end 2, a third connection end 3 and a fourth connection end 4 which are respectively used for being connected with an anode connection end, a cathode connection end, an anode connection end and a cathode connection end of a direct current load of a direct current bus. The first connection end 1 of the reverse polarity connection protection circuit is respectively connected with the anode of the diode D1 and the cathode of the diode D3, the second connection end 2 of the reverse polarity connection protection circuit is respectively connected with the cathode of the diode D1 and the cathode of the diode D4, the third connection end 3 of the reverse polarity connection protection circuit is respectively connected with the anode of the diode D2 and the anode of the diode D3, and the fourth connection end 4 of the reverse polarity connection protection circuit is respectively connected with the cathode of the diode D2 and the anode of the diode D4. Furthermore, in the reverse polarity protection circuit, fuses FU1 and FU2 are further arranged, fuse FU1 is connected between the negative electrode of diode D1 and the second connection end of the reverse polarity protection circuit, fuse FU2 is connected between the positive electrode of diode D4 and the fourth connection end of the reverse polarity protection circuit, and fuses FU1 and FU2 are used for fusing when the current of the direct current bus is too large, so that the direct current bus is protected.

The residual charge discharging circuit comprises resistors R1, R2, R3 and R4, and a first connecting end 5, a second connecting end 6, a third connecting end 7 and a fourth connecting end 8 which are respectively used for being connected with a positive connecting end, a negative connecting end of a direct current bus, a positive connecting end and a negative connecting end of a direct current load. The resistors R1, R2 are connected in series between the second connection 6 and the third connection 7 of the residual charge discharge circuit, and the resistors R3, R4 are connected in series between the first connection 5 and the fourth connection 8 of the residual charge discharge circuit.

As shown in fig. 2, the switching module includes a rotating member, a driving circuit, a stepping motor, and a rotating shaft. The rotating component is used for bearing the plurality of protection circuits, and when the rotating component rotates to a set angle, the four connecting ends of the polarity reverse connection protection circuit or the residual charge discharge circuit are just connected with the positive connecting end and the negative connecting end of the direct current bus, and the positive connecting end and the negative connecting end of the direct current load. The rotating shaft is connected with the rotating part, the stepping motor is connected with the rotating shaft, the driving circuit is connected with the stepping motor and used for sending out a driving signal to drive the stepping motor to rotate, so that the rotating part is driven to rotate. The four connecting ends of the polarity reverse connection protection circuit and the residual charge discharge circuit are arranged at four corners of a square with the rotating shaft as the center, so that when the rotating part rotates to a set angle, the four connecting ends of the polarity reverse connection protection circuit or the residual charge discharge circuit are connected with the positive connecting end, the negative connecting end and the positive connecting end and the negative connecting end of the direct-current bus, and the positive connecting end and the negative connecting end of the direct-current load are connected with the rotating part.

The operation principle of the dc bus protection device of the converter is explained below.

As shown in fig. 3, when the dc load is normally connected, the current at the positive terminal of the dc bus flows into the dc load through the diode D1, and then flows back to the negative terminal of the dc bus through the diode D2. As shown in fig. 4, when the dc load is reversely connected, the current at the positive terminal of the dc bus flows into the dc load through the diode D4 and flows back to the negative terminal of the dc bus through the diode D3, so that the dc load can normally operate when reversely connected, and the problems of capacitor explosion and dc load damage caused by polarity reverse connection are avoided.

As shown in fig. 5, when a large-capacitance dc load is adjusted or dc bus voltage needs to be discharged, the rotation angle α is controlled to be 45 degrees, so that 5-8 contacts are connected with 4 connection points, the resistors R1 and R2 are connected in series between the dc loads, the resistors R3 and R4 are connected in series between the dc buses, and the residual charge of the capacitor can be discharged rapidly through the series resistors).

As shown in fig. 6, when a user needs to perform adjustment such as replacement, maintenance, etc. on the dc load, the user may directly send a relevant instruction to the switching module through the control module, and the switching module, after receiving the instruction information, controls the stepping motor to rotate by a certain angle through the driving circuit, so that the four connection points of the protection circuit are disconnected from the dc bus and the dc load, and the electrical connection between the dc bus and the dc load is indirectly disconnected. For some non-capacitive or small-capacitance value direct current loads, a user can directly adjust the direct current loads, the direct current loads are controlled to be connected to the direct current bus through a user instruction after adjustment, the direct current bus operates again, the system does not need to be powered off in the whole process, and the work of the direct current bus or the power supply of other direct current loads is not influenced.

The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.

Claims

1. A converter direct current bus protection device is characterized by comprising: the protection circuit comprises a switching module and a plurality of protection circuits with different functions, wherein the protection circuits are used for being connected between a direct current bus and a direct current load, and the switching module is used for switching the protection circuits connected between the direct current bus and the direct current load.

2. The converter direct current bus protection device according to claim 1, wherein the protection circuit comprises a first connection end, a second connection end, a third connection end and a fourth connection end for respectively connecting with the positive connection end, the negative connection end of the direct current bus, the positive connection end and the negative connection end of the direct current load, and the switching module is used for controlling connection and disconnection of the four connection ends of the protection circuit with the positive connection end, the negative connection end, the positive connection end and the negative connection end of the direct current bus.

3. The converter dc bus bar protection device according to claim 2, wherein the switching module comprises a rotating member for carrying the plurality of protection circuits, and when the rotating member rotates to a set angle, four connection terminals of the protection circuits are just connected to the positive connection terminal, the negative connection terminal of the dc bus bar, the positive connection terminal and the negative connection terminal of the dc load.

4. The converter dc bus protection device as claimed in claim 3, wherein the switching module further comprises a driving circuit, a stepping motor and a rotating shaft, the rotating shaft is connected to the rotating component, the stepping motor is connected to the rotating shaft, the driving circuit is connected to the stepping motor, and the driving circuit is configured to drive the stepping motor to rotate so as to drive the rotating component to rotate.

5. The converter dc bus bar protection device according to claim 4, wherein four connection terminals of said protection circuit are disposed at four corners of a square centered on said rotation shaft.

6. The converter dc bus protection device of claim 2, wherein said plurality of protection circuits includes a reverse polarity protection circuit and a residual charge discharge circuit.

7. The converter direct-current bus protection device as claimed in claim 6, wherein the reverse polarity protection circuit comprises diodes D1, D2, D3 and D4, a first connection end of the reverse polarity protection circuit is respectively connected with an anode of diode D1 and a cathode of diode D3, a second connection end of the reverse polarity protection circuit is respectively connected with a cathode of diode D1 and a cathode of diode D4, a third connection end of the reverse polarity protection circuit is respectively connected with an anode of diode D2 and an anode of diode D3, and a fourth connection end of the reverse polarity protection circuit is respectively connected with a cathode of diode D2 and an anode of diode D4.

8. The converter dc bus protection device of claim 7, wherein said reverse polarity protection circuit further comprises fuses FU1, FU2, fuse FU1 is connected between the cathode of diode D1 and the second connection terminal of said reverse polarity protection circuit, fuse FU2 is connected between the anode of diode D4 and the fourth connection terminal of said reverse polarity protection circuit.

9. The converter DC bus protection device as claimed in claim 6, wherein said residual charge discharging circuit comprises resistors R1, R2, R3 and R4, wherein the resistors R1 and R2 are connected in series between the second connection terminal and the third connection terminal of said residual charge discharging circuit, and wherein the resistors R3 and R4 are connected in series between the first connection terminal and the fourth connection terminal of said residual charge discharging circuit.

10. The converter dc bus protection device of claim 1, further comprising a control module connected to said switching module, said control module configured to transmit a switching command from a user to said switching module.