SUMMERY OF THE UTILITY MODEL
Aiming at the defects of the prior art, the utility model provides a direct-current power supply system which can realize the sharing and the maximum utilization of a direct-current power supply and improve the safety and the reliability of a power grid system.
The technical scheme of the utility model is realized as follows: a direct-current power supply system comprises a direct-current power supply device I, a direct-current power supply device II, a direct-current power supply device III, a first bidirectional DC/DC converter, a second bidirectional DC/DC converter, a first direct-current bus and a second direct-current bus;
the direct current power supply equipment I is connected with one end of the first bidirectional DC/DC converter through the first direct current bus;
the direct current power supply equipment II is connected with the other end of the first bidirectional DC/DC converter through the second direct current bus;
the direct current power supply equipment III is connected with the first direct current bus through the second bidirectional DC/DC converter;
the first bidirectional DC/DC converter and the second bidirectional DC/DC converter comprise IGBT devices, a controller, a PWM driving circuit and a transformer, wherein the controller drives the PWM driving circuit to operate through a control signal to realize on-off control of the IGBT devices;
when the direct current supply equipment I is in an open circuit, the direct current supply equipment II and the first bidirectional DC/DC converter form a first power supply path; the direct current power supply device III and the second bidirectional DC/DC converter form a second power supply path; by controlling the controllers in the first bidirectional DC/DC converter and the second bidirectional DC/DC converter, the first power supply path or the second power supply path can supply power to the load connected on the first direct current bus.
Further, the direct current supply device i, the direct current supply device ii, and the direct current supply device iii have different supply voltages, the transformer in the first bidirectional DC/DC converter is used to implement voltage conversion between the direct current supply device i and the direct current supply device ii, and the transformer in the second bidirectional DC/DC converter is used to implement voltage conversion between the direct current supply device i and the direct current supply device iii.
Furthermore, the power supply voltages of the direct current supply equipment I, the direct current supply equipment II and the direct current supply equipment III are 220V, 110V and 48V respectively.
Furthermore, controllers in the first bidirectional DC/DC converter and the second bidirectional DC/DC converter are connected with a remote control system, and the remote control system is used for controlling the on-off of the first bidirectional DC/DC converter and the second bidirectional DC/DC converter.
Further, the first bidirectional DC/DC converter and the second bidirectional DC/DC converter are both provided with short-circuit protection circuits, and the arrangement of the short-circuit protection circuits enables the direct-current power supply system to be safer and more stable.
Further, the direct-current power supply system further comprises a third bidirectional DC/DC converter, a fourth bidirectional DC/DC converter and a direct-current power supply device iv, the third bidirectional DC/DC converter and the fourth bidirectional DC/DC converter have the same structure as the first bidirectional DC/DC converter and the second bidirectional DC/DC converter, the direct-current power supply device iv is connected with the second direct-current bus through the third bidirectional DC/DC converter, one end of the fourth bidirectional DC/DC converter is connected with the second bidirectional DC/DC converter, and the other end of the fourth bidirectional DC/DC converter is connected with the third bidirectional DC/DC converter; the first bidirectional DC/DC converter, the second bidirectional DC/DC converter, the fourth bidirectional DC/DC converter and the third bidirectional DC/DC converter are sequentially connected into a closed-loop structure.
Furthermore, the direct current supply device i, the direct current supply device ii, the direct current supply device iii, and the direct current supply device iv have different supply voltages, the transformer in the third bidirectional DC/DC converter is used to implement voltage conversion between the direct current supply device iv and the direct current supply device ii, and the transformer in the fourth bidirectional DC/DC converter is used to implement voltage conversion between the direct current supply device iv and the direct current supply device iii.
Particularly, the power supply voltages of the direct current supply equipment I, the direct current supply equipment II, the direct current supply equipment III and the direct current supply equipment IV are 220V, 110V, 48V and 48V respectively.
Furthermore, the controllers in the third bidirectional DC/DC converter and the fourth bidirectional DC/DC converter are connected with a remote control system, and the on-off of the third bidirectional DC/DC converter and the fourth bidirectional DC/DC converter is controlled by the remote control system.
Still further, the third and fourth bidirectional DC/DC converters each have a short-circuit protection circuit.
Compared with the prior art, the direct-current power supply system has the beneficial effects that the plurality of direct-current power supply devices are physically isolated from each other and do not interfere with each other, and the circulation risk caused by parallel connection can not occur at any time, so that the risk of failure of the direct-current power supply system caused by circulation is avoided, and the safety and the reliability of the direct-current power supply system are greatly improved; the plurality of direct current power supply devices and the bidirectional DC/DC converter can form a plurality of power supply paths, so that a plurality of spare power supply paths are provided for a plurality of loads, direct and indirect cost losses caused by faults are reduced, and sharing and maximum utilization of the direct current power supply devices are realized; the utility model can realize remote control, thereby avoiding the workload caused by manual field operation in the prior art and further reducing the expenditure of labor cost.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 1, a dc power supply system includes: the DC power supply apparatus I11, the DC power supply apparatus ii 12, the DC power supply apparatus iii 13, the first bidirectional DC/DC converter 21, the converter second bidirectional DC/DC converter 22, the first DC bus 31, the second DC bus 32, and the controller (not shown).
The DC power supply I11 is connected to one end of the first bidirectional DC/DC converter 21 of the converter through the first DC bus 31. The direct current power supply device I11 is a 220V direct current power supply device, which comprises a rectifier I and a 220V battery pack, wherein under normal conditions, the rectifier I converts commercial power into direct current to supply power to the load I, and when the commercial power is abnormal, the 220V battery pack supplies power to the load I.
The direct current supply equipment II 12 is connected with the other end of the converter first bidirectional DC/DC converter 21 through the second direct current bus 32; the direct current supply equipment II 12 is 110V direct current supply equipment and comprises a rectifier II and a 110V storage battery pack.
The first bidirectional DC/DC converter is connected between the DC power supply I11 and the DC power supply ii 12 for converting 220V DC power to 110V DC power and for converting 110V DC power to 220V DC power.
The direct current power supply device iii 13 is connected to the first direct current bus 31 through the converter second bidirectional DC/DC converter 22; the direct current power supply equipment III 13 is 48V direct current power supply equipment and comprises a rectifier III and a 48V battery pack.
The second bidirectional DC/DC converter 22 is connected between the DC power supply I11 and the DC power supply iii 13, and is configured to convert 48V DC power to 220V DC power and to convert 220V DC power to 48V DC power.
In this embodiment, the first bidirectional DC/DC converter 21 and the second bidirectional DC/DC converter 22 are respectively provided with an IGBT device, a PWM driving circuit, a transformer, and a short-circuit protection circuit, and the controller is configured to send a control signal to drive the PWM driving circuit to operate, so as to implement on-off control of the IGBT device, and further implement on-off control of the first bidirectional DC/DC converter and the second bidirectional DC/DC converter. The short-circuit protection circuit is arranged, so that the direct-current power supply system is safer and more stable.
When the direct current supply device I11 is open due to an abnormality, the load I connected to the first direct current bus 31 has two selectable power supply paths, wherein the direct current supply device II 12 and the converter first bidirectional DC/DC converter 21 form a first power supply path; the DC supply device iii 13 forms a second supply path with the converter second bidirectional DC/DC converter 22. At this time, the controller selects the first power supply path or the second power supply path to supply power to the load I according to actual conditions, so that a plurality of standby power supply paths are provided for the load I, and it is ensured that the load I does not have power supply interruption.
In this embodiment, the converter first bidirectional DC/DC converter 21 is disposed between the DC power supply device I11 and the DC power supply device ii 12, and the converter second bidirectional DC/DC converter 22 is disposed between the DC power supply device iii 13 and the DC power supply device I11, so that the DC power supply device I11 and the DC power supply device ii 12, and the DC power supply device iii 13 and the DC power supply device I11 are physically isolated from each other and do not interfere with each other, and a risk of circulating current caused by parallel connection does not occur at any time, thereby avoiding a risk of failure of a DC power supply system due to circulating current, and greatly improving safety and reliability of the DC power supply system.
Example 2
Referring to fig. 2, embodiment 2 is different from embodiment 1 in that in embodiment 2, the DC power supply system is further provided with a third bidirectional DC/DC converter 23, a fourth bidirectional DC/DC converter 24, and a DC power supply device iv 14.
The third bidirectional DC/DC converter 23 is for converting the 48V DC power to 110V DC power and for converting the 110V DC power to 48V DC power; the fourth bi-directional DC/DC converter 24 is for converting 48 vdc to 48 vdc and is bi-directional.
The DC power supply device iv 14 is connected to the second DC bus 32 through the third bidirectional DC/DC converter 23. The direct current power supply device IV 14 is a 48V direct current power supply device and comprises a rectifier IV and a 48V battery pack, and one end of the fourth bidirectional DC/DC converter 24 is connected with the second bidirectional DC/DC converter;
the other end of the fourth bidirectional DC/DC converter 24 is connected to the third bidirectional DC/DC converter 23; the first bidirectional DC/DC converter 21, the second bidirectional DC/DC converter 22, the fourth bidirectional DC/DC converter 24, and the third bidirectional DC/DC converter 23 are sequentially connected in a closed-loop configuration.
Since the first bidirectional DC/DC converter 21, the second bidirectional DC/DC converter 22, the fourth bidirectional DC/DC converter 24, and the third bidirectional DC/DC converter 23 are sequentially connected in a closed loop structure. When any one of the direct current supply equipment I11, the direct current supply equipment II 12, the direct current supply equipment III 13 and the direct current supply equipment IV 14 fails, the rest three direct current supply equipment can be used as standby power supply, so that direct and indirect cost loss caused by failure is reduced.
Taking the dc power supply device I11 as an example of an abnormality, the load I connected to the dc power supply device I11 has the following power supply path:
the first power supply path is composed of the direct current power supply equipment II 12 and the first bidirectional DC/DC converter 21; the second power supply path is composed of the direct current power supply device III 13 and the second bidirectional DC/DC converter 22; the third power supply path is composed of the direct current power supply device IV 14, the third bidirectional DC/DC converter 23 and the first bidirectional DC/DC converter 21; the fourth power supply path is composed of the DC power supply device iv 14, the fourth bidirectional DC/DC converter 24, and the second bidirectional DC/DC converter 22.
The controller can select one of the power supply paths to supply power to the load I.
Taking the case that the dc power supply device I11, the dc power supply device ii 12, and the dc power supply device iii 13 are all abnormal, the load I, the load ii, and the load iii can all be supplied with power by the dc power supply device iv 14.
Specifically, the load i has two power supply paths, the first is: the direct current power supply device IV 14, the third bidirectional DC/DC converter 23 and the first bidirectional DC/DC converter are connected in sequence to form a power supply path; the second method is as follows: the direct current power supply device iv 14, the fourth bidirectional DC/DC converter 24, and the second bidirectional DC/DC converter are connected in sequence to form a power supply path. And one of the two power supply paths is controlled and selected by the controller.
The power supply path of the load II consists of the direct current power supply device IV 14 and the third bidirectional DC/DC converter 23.
The power supply path of the load III is composed of the direct current power supply device IV 14 and the fourth bidirectional DC/DC converter 24.
The dc power supply system in this example can effectively avoid the situation that any one of the load i, the load ii, the load iii, and the load iv is interrupted, thereby effectively avoiding the loss caused by the interruption of power supply.
In addition, the controllers arranged on the two-way DC/DC converters are connected with a remote control system, and the remote control system is used for controlling the on-off of the two-way DC/DC converters to realize remote control, so that the workload caused by manual field operation in the prior art is avoided, and the expenditure of labor cost is reduced.
In this embodiment, the voltage classes of the four DC power supply devices are not limited, the DC power supply devices of the same or different voltage classes can be compatible in the same DC power supply system, and each bidirectional DC/DC converter can be flexibly configured according to the voltage and power between adjacent DC power supply devices, thereby realizing the resource sharing and utilization maximization of the DC power supply.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the utility model.