Light storage firewood net seamless power supply device

Abstract

The embodiment of the utility model provides a seamless power supply device for an optical storage diesel power grid, which relates to the technical field of electric energy application and comprises a photovoltaic system, a battery energy storage system, a diesel generating set, a power grid, an electric power conversion system and a direct current bus. Wherein the photovoltaic system is connected with the direct current bus; the battery energy storage system is connected with the direct current bus; the diesel generating set and the power grid are both connected with the power conversion system, and the power conversion system is connected with the direct current bus; and the direct current bus is also connected with an external alternating current load. The power supply device can realize seamless switching power supply through DC bus coupling, photovoltaic, energy storage, a diesel generating set and a power grid.

Description

Technical Field

[0001] This utility model relates to the field of power application technology, and more specifically, to a seamless power supply device for photovoltaic, energy storage, diesel, and power grid. Background Technology

[0002] While traditional photovoltaic + energy storage + diesel generator sets can provide a stable power supply, they are typically used as off-grid systems and cannot participate in grid dispatch. Diesel generator sets, as backup power sources, are connected in parallel with the AC bus of the system, which presents problems such as complex power supply systems and large diesel generator set capacities. Utility Model Content

[0003] An embodiment of this utility model provides a seamless power supply device for photovoltaic, energy storage, diesel, and power grids to solve the technical problems existing in the prior art.

[0004] Other features and advantages of this invention will become apparent from the following detailed description, or may be learned in part by practice of this invention.

[0005] According to a first aspect of the present invention, a seamless power supply device for photovoltaic, energy storage, diesel generator set, power grid, power conversion system and DC bus is provided.

[0006] The photovoltaic system is connected to the DC bus.

[0007] The battery energy storage system is connected to the DC bus;

[0008] Both the diesel generator set and the power grid are connected to the power conversion system, and the power conversion system is connected to the DC bus.

[0009] The DC bus is also connected to an external AC load.

[0010] In some embodiments of this utility model, based on the aforementioned scheme, a DC-DC module is connected between the photovoltaic system and the DC bus.

[0011] In some embodiments of this utility model, based on the aforementioned scheme, a DC-AC inverter is connected between the DC bus and the AC load.

[0012] In some embodiments of this utility model, based on the aforementioned scheme, the power conversion system is equipped with a controller, which is communicatively connected to the DC-DC module, the DC-AC inverter, the battery energy storage system, the diesel generator set, and the power grid.

[0013] In some embodiments of this utility model, based on the foregoing scheme, the battery energy storage system is equipped with a BMS, and the BMS is communicatively connected to the controller.

[0014] In some embodiments of this utility model, based on the foregoing scheme, the power conversion system is connected to a lead-acid battery.

[0015] In some embodiments of this utility model, based on the aforementioned scheme, the diesel generator set is connected to the power conversion system through a first control switch KM1, and the power grid is connected to the power conversion system through a second control switch KM2, wherein the first control switch KM1 and the second control switch KM2 are interlocked.

[0016] In some embodiments of this utility model, based on the aforementioned scheme, the diesel generator set and the power grid are connected to the AC load through a bypass switch QF1.

[0017] The technical solution of this utility model has the following beneficial effects:

[0018] The power grid and AC loads are not directly connected, allowing the system to operate in grid-connected mode and participate in grid dispatch. The diesel generator set is connected to the DC bus via a power conversion system, and the coupling via the DC bus avoids the phase-locking problems that exist in AC parallel connection in traditional schemes, simplifying control. The battery energy storage system's DC-DC converter is eliminated, improving the charging and discharging efficiency of the battery energy storage system.

[0019] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the present invention. Attached Figure Description

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments conforming to the present invention and, together with the description, serve to explain the principles of the present invention. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0021] Figure 1 A schematic diagram of a seamless power supply device for solar energy storage and diesel grid according to an embodiment of the present invention is shown. Detailed Implementation

[0022] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0023] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a full understanding of embodiments of the present invention. However, those skilled in the art will recognize that the technical solutions of the present invention can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., may be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of the present invention.

[0024] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0025] The following description, in conjunction with the accompanying drawings, details some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0026] See Figure 1 The diagram shows a structural schematic of a seamless power supply device for solar energy storage and diesel grid according to an embodiment of the present invention.

[0027] like Figure 1 As shown, a seamless power supply device integrating photovoltaic, energy storage, diesel generator set, power grid, power conversion system and DC bus is demonstrated.

[0028] The photovoltaic system is connected to the DC bus.

[0029] The battery energy storage system is connected to the DC bus;

[0030] Both the diesel generator set and the power grid are connected to the power conversion system, and the power conversion system is connected to the DC bus.

[0031] The DC bus is also connected to an external AC load.

[0032] It is understood that in this embodiment, the power grid and the AC load are not directly connected, ensuring that the system can operate in grid-connected state and participate in grid dispatch; the diesel generator set is connected to the DC bus through the power conversion system, and the coupling through the DC bus avoids the phase-locking problem that exists in AC parallel connection in traditional schemes, and the control is simple.

[0033] In some feasible embodiments, based on the aforementioned scheme, a DC-DC module is connected between the photovoltaic system and the DC bus.

[0034] It is understood that in this embodiment, the photovoltaic system is connected to the DC bus through a DC-DC module, and supplies power to the DC bus when the photovoltaic system is working.

[0035] It should be noted that in this embodiment, the DCDC module refers to a DC-DC converter, which is a device that converts electrical energy of one voltage value into electrical energy of another voltage value in a DC circuit.

[0036] In some feasible embodiments, based on the aforementioned scheme, a DC-AC inverter is connected between the DC bus and the AC load.

[0037] It is understood that in this embodiment, the AC load is connected to the DC bus via a DCAC inverter, and the DC power on the DC bus is converted into the AC power required by the AC load by the DCAC inverter.

[0038] It should be noted that in this embodiment, the DCAC inverter refers to a DC-AC inverter or DC-AC converter, which is a power electronic device whose main function is to convert direct current (DC) into alternating current (AC).

[0039] In some feasible embodiments, based on the aforementioned scheme, the power conversion system is equipped with a controller, which is communicatively connected to the DC-DC module, the DC-AC inverter, the battery energy storage system, the diesel generator set, and the power grid.

[0040] In some feasible embodiments, based on the aforementioned scheme, the battery energy storage system is equipped with a BMS and a high-voltage box, the BMS is communicatively connected to the controller, and the high-voltage box is connected to the DC bus.

[0041] It should be noted that BMS refers to Battery Management System, which is an electronic device used to monitor, manage, and protect battery systems.

[0042] It should be noted that in this embodiment, the battery energy storage system is directly connected to the DC bus, eliminating the original DC-DC charging and discharging module. The battery is charged through the power conversion system and the DC-DC module, thereby improving the charging and discharging efficiency.

[0043] In some feasible embodiments, based on the foregoing scheme, the power conversion system is connected to a lead-acid battery.

[0044] It should be noted that lead-acid batteries provide auxiliary power to the power conversion system. Before the power conversion system equipment is turned on, the lead-acid batteries supply power to the system to start the power supply system.

[0045] In some feasible embodiments, based on the aforementioned scheme, the diesel generator set is connected to the power conversion system through a first control switch KM1, and the power grid is connected to the power conversion system through a second control switch KM2, wherein the first control switch KM1 and the second control switch KM2 are interlocked.

[0046] It should be noted that, in this embodiment, as Figure 1 As shown, the oil generator set and the power grid do not supply power to the power conversion system at the same time, and interlocking is achieved through the first control switch KM1 and the second control switch KM2.

[0047] In some feasible embodiments, based on the aforementioned scheme, the diesel generator set and the power grid are connected to the AC load via a bypass switch QF1.

[0048] It should be noted that in this embodiment, the diesel generator set and the power grid supply power to the AC load through the bypass switch QF1, which can ensure uninterrupted power supply when the equipment is malfunctioning or during maintenance.

[0049] It should be noted that, in this embodiment, as Figure 1 As shown, the diesel generator set is connected to the power conversion system through the first control switch KM1, which rectifies the AC power generated by the diesel generator set into DC power and supplies it to the DC bus.

[0050] The power grid is connected to the power conversion system through the second control switch KM2, which rectifies the AC power from the power grid into DC power and supplies it to the DC bus. At the same time, the DC power output from the photovoltaic system and the battery energy storage system is connected to the power grid through the DC bus and the power conversion system to participate in the power grid dispatch.

[0051] In this embodiment, the photovoltaic system can supply power to AC loads, charge the battery energy storage system, and operate in grid-connected mode; the battery energy storage system can supply power to AC loads and operate in grid-connected mode; the diesel generator set can supply power to AC loads, charge the battery energy storage system, and supply power to the grid; the grid can supply power to the battery energy storage system.

[0052] The following provides the working logic of a seamless power supply device for photovoltaic, energy storage, diesel, and grid provided in this embodiment.

[0053] The photovoltaic system prioritizes supplying power to the AC load. When the power provided by the photovoltaic system is greater than the power required by the AC load, the excess power is used to charge the battery energy storage system. When the power provided by the photovoltaic system is less than the power required by the AC load, the battery energy storage system provides the excess power. When the power provided by the photovoltaic system is less than the power required by the AC load, and the battery energy storage system's charge is less than the minimum charge threshold (e.g., SOC = 10%), the diesel generator set provides the excess power.

[0054] When there is no photovoltaic power, the battery energy storage system provides AC load power. When the power provided by the battery energy storage system is less than the power required by the AC load, the diesel generator set provides the excess power. When the power of the battery energy storage system is less than the minimum power threshold (e.g., SOC = 10%), the diesel generator set provides the excess power.

[0055] When the device is without power, it can be started using a diesel generator set;

[0056] When the amount of electricity generated by the photovoltaic system is much greater than the amount of electricity required by the AC load, the photovoltaic system generates electricity by connecting to the grid and participates in power dispatch.

[0057] When the battery energy storage system has low power, it can be charged by a diesel generator set or by the power grid (in areas where the power grid is stable).

[0058] Bypass power supply: The diesel generator set and the power grid supply power to the AC load through the bypass switch QF1, which can ensure uninterrupted power supply when the equipment is abnormal or during maintenance.

[0059] This power supply unit can achieve seamless switching of power supply from photovoltaic, energy storage, diesel generator sets and the power grid through DC bus coupling.

[0060] In summary, this power supply device has the following advantages:

[0061] (1) This power supply device is coupled via DC bus, making control simple;

[0062] (2) The DCDC charging and discharging module is eliminated in the battery energy storage system, thereby improving the charging and discharging efficiency of the battery energy storage system;

[0063] (3) The diesel generator set is connected to the DC bus through the power conversion system, which can provide stable power supply and achieve seamless switching of power supply from the diesel generator set; through the configuration of energy storage, the capacity of the diesel generator set does not need to be too large, saving system costs;

[0064] (4) The power supply equipment can participate in the power grid dispatching and improve the efficiency of power utilization;

[0065] (5) In case of equipment maintenance or abnormality, power can be supplied through a bypass to improve flexibility.

[0066] Other embodiments of the present invention will readily occur to those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. It should be understood that the present invention is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A seamless power supply device for photovoltaic-storage-diesel grid, characterized in that, include: Photovoltaic systems, battery energy storage systems, diesel generator sets, power grids, power conversion systems, and DC buses; The photovoltaic system is connected to the DC bus. The battery energy storage system is connected to the DC bus; Both the diesel generator set and the power grid are connected to the power conversion system, and the power conversion system is connected to the DC bus. The DC bus is also connected to an external AC load.

2. The apparatus according to claim 1, characterized in that, A DC-DC module is connected between the photovoltaic system and the DC bus.

3. The apparatus according to claim 2, characterized in that, A DC-AC inverter is connected between the DC bus and the AC load.

4. The apparatus according to claim 3, characterized in that, The power conversion system is equipped with a controller, which is connected to the DC-DC module, the DC-AC inverter, the battery energy storage system, the diesel generator set, and the power grid.

5. The apparatus according to claim 4, characterized in that, The battery energy storage system is equipped with a BMS and a high-voltage box. The BMS is communicatively connected to the controller, and the high-voltage box is connected to the DC bus.

6. The apparatus according to any one of claims 1-5, characterized in that, The power conversion system is connected to a lead-acid battery.

7. The apparatus according to any one of claims 1-5, characterized in that, The diesel generator set is connected to the power conversion system via a first control switch KM1, and the power grid is connected to the power conversion system via a second control switch KM2, wherein the first control switch KM1 and the second control switch KM2 are interlocked.

8. The apparatus according to any one of claims 1-5, characterized in that, The diesel generator set and the power grid are connected to the AC load via a bypass switch QF1.

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