Lithium battery hybrid super capacitor energy storage photovoltaic micro-grid power supply device

Abstract

The utility model discloses a lithium battery hybrid super capacitor energy storage photovoltaic micro-grid power supply device, which relates to the technical field of new energy storage and comprises an electrical cabinet box body, a junction box is arranged on the rear side of the electrical cabinet box body, and a converter and an energy storage assembly are arranged in the electrical cabinet box body; the energy storage assembly comprises a lithium battery pack and a super capacitor bank. One end of the converter is connected with an external photovoltaic device through a junction box; the other end of the converter is connected with the lithium battery pack and the super capacitor bank, and is connected with a power grid through the junction box; according to the utility model, the energy storage technology of the lithium battery and the super capacitor is integrated, the high-power and high-capacity performance is realized at the same time, and efficient storage and release of energy are realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to new energy storage technology field, concretely relates to a kind of photovoltaic microgrid power device of lithium battery mixed supercapacitor energy storage. BACKGROUND

[0002] The statements in this section merely provide background information related to the present disclosure and can not constitute prior art.

[0003] With the development and application of renewable energy, microgrid system as a new energy supply mode, gradually receives extensive attention. Photovoltaic power generation as an important part of microgrid system, has clean, renewable and other advantages, however photovoltaic power generation system is influenced by weather and sunshine change and other factors, the volatility and instability of its output bring certain challenge to the operation of microgrid.

[0004] In microgrid system, energy storage technology plays a vital role, can balance the mismatch between energy supply and demand, and improve the stability and reliability of system. Traditional energy storage technology is mainly battery energy storage or supercapacitor energy storage. Battery has higher energy density and stability, is suitable for long-term energy storage and release, but its power density is lower, cannot release or store a large amount of energy in short term, charge-discharge times are limited, service life is limited. Supercapacitor has higher power density, long cycle life and fast charge-discharge characteristics, is suitable for transient energy storage and release, but energy density is lower, cannot meet long-term energy storage demand. UTILITY MODEL CONTENTS

[0005] The utility model relates to a kind of 20kw grade lithium battery mixed supercapacitor energy storage photovoltaic microgrid power device, aims at making up the deficiency of traditional photovoltaic microgrid device in short-term and long-term energy supply, overcoming the problem of traditional photovoltaic power fluctuation and instability. The device combines the energy storage technology of lithium battery and supercapacitor, has high power and high capacity performance simultaneously, realizes the efficient storage and release of energy, and at the same time, utilizes heat dissipation air duct to dissipate heat for lithium battery and supercapacitor, to improve the energy utilization efficiency and stability of microgrid.

[0006] The technical scheme of the utility model is as follows:

[0007] A kind of photovoltaic microgrid power device of lithium battery mixed supercapacitor energy storage, comprising: electrical cabinet box body, the electrical cabinet box body rear side is provided with terminal box, the electrical cabinet box body inside is provided with converter and energy storage component;

[0008] The energy storage component includes: lithium battery group and supercapacitor group;

[0009] One end of the converter is connected with external photovoltaic device through the terminal box; the other end of the converter is connected with the lithium battery group and the super capacitor group on one hand, and connected with the power grid through the terminal box on the other hand.

[0010] Further, the terminal box comprises an AC measurement three-phase interface, a DC side positive and negative electrode interface and a cabinet grounding interface; the AC measurement three-phase interface is used for connecting with the 10kV three-phase AC microgrid, and the DC side positive and negative electrode interface is used for connecting with the external photovoltaic device.

[0011] Further, the AC measurement three-phase interface comprises an A-phase interface, a B-phase interface and a C-phase interface; the DC side positive and negative electrode interface comprises a positive electrode interface and a negative electrode interface.

[0012] Further, the converter comprises a DC\DC converter and a DC\AC inverter; part of the electric energy input by the external photovoltaic device is output to the 10kV three-phase AC microgrid through the DC\DC converter and the DC\AC inverter, and another part of the electric energy is stored in the lithium battery group and the super capacitor group through the DC\DC converter, and the electric energy stored in the lithium battery group and the super capacitor group can be output to the 10kV three-phase AC microgrid through the DC\DC converter and the DC\AC inverter.

[0013] Further, the converter further comprises a 25kV DC bus;

[0014] The DC\DC converter comprises three, which are a first DC\DC converter, a second DC\DC converter and a third DC\DC converter; one end of the first DC\DC converter is connected with the external photovoltaic device through the terminal box, and the other end of the first DC\DC converter is connected with the 25kV DC bus; one end of the second DC\DC converter is connected with the 25kV DC bus, and the other end of the second DC\DC converter is connected with the lithium battery group; one end of the third DC\DC converter is connected with the 25kV DC bus, and the other end of the third DC\DC converter is connected with the super capacitor group.

[0015] Further, the lithium battery group is connected with the bottom of the electrical cabinet box body through the first support column and the second support column, and the super capacitor group is located on the upper side of the lithium battery group.

[0016] Further, the front of the electrical cabinet box body is provided with an electrical cabinet door.

[0017] Further, the electrical cabinet box body is further provided with a heat dissipation device.

[0018] Further, the heat dissipation device comprises a heat dissipation air duct arranged inside the electrical cabinet box body, an air outlet arranged above the electrical cabinet box body and an air inlet arranged below the electrical cabinet box body.

[0019] Further, the air inlet is provided with a heat dissipation fan, and the air outlet is provided with a heat dissipation grille.

[0020] Compared with the prior art, the utility model has the advantages that:

[0021] 1. The device can provide large power demand for the micro-grid in a short time, meet the sudden load demand, and also store electric energy for a long time to cope with daily energy fluctuations. This double support can effectively balance the difference between energy supply and demand, and improve the stability of the micro-grid system.

[0022] 2. The device adopts a heat dissipation fan and a heat dissipation air duct, effectively adjusts the temperature of the device, improves the heat dissipation efficiency, enables the device to operate stably for a long time, prolongs the service life of the equipment, and reduces the maintenance cost of the system.

[0023] 3. The device uses a battery and a super capacitor in combination, can dynamically adjust the use state of the two according to actual needs, avoids the problem of shortened service life caused by frequent charging and discharging of a single device, thereby prolonging the service life of the device and reducing the system maintenance cost. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a front structure schematic view of the utility model;

[0025] Fig. 2 is a back structure schematic view of the utility model;

[0026] Fig. 3 is a side structure sectional view of the utility model.

[0027] Mark: 1-electrical cabinet box body, 2-energy storage assembly, 3-heat dissipation device, 4-junction box, 12-electrical cabinet door, 21-converter, 22-lithium battery pack, 23-super capacitor pack, 31-heat dissipation fan, 32-heat dissipation grille, 111-heat dissipation air duct, 112-air inlet, 113-air outlet, 121-first support column, 122-second support column, 211-25kV DC bus, 411-A phase interface, 412-B phase interface, 413-C phase interface, 421-positive electrode interface, 422-negative electrode interface, 423-casing grounding interface. DETAILED DESCRIPTION

[0028] It is to be noted that the relational terms herein, such as first and second, and the like, are used solely to distinguish one from another entity or action without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the presence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0029] The features and performance of the present application will be described in further detail below with reference to the embodiments.

[0030] Embodiment One

[0031] Please refer to Figs. 1-3 A photovoltaic micro-grid power supply device with lithium battery hybrid super capacitor energy storage, specifically comprising the following structure:

[0032] The electrical cabinet box 1 is provided with a junction box 4 at the rear side, and a current transformer and an energy storage assembly 2 are arranged inside the electrical cabinet box 1.

[0033] The energy storage assembly 2 comprises a lithium battery pack 22 and a super capacitor pack 23.

[0034] One end of the current transformer is connected with an external photovoltaic device through the junction box 4, and the other end of the current transformer is connected with the lithium battery pack 22 and the super capacitor pack 23 on one hand, and connected with the power grid through the junction box 4 on the other hand.

[0035] In this embodiment, specifically, the junction box 4 comprises a three-phase interface for AC measurement, positive and negative interfaces on the DC side, and a shell grounding interface 423; the three-phase interface for AC measurement is used to connect with a 10kV, 50Hz three-phase AC micro-grid, and the positive and negative interfaces on the DC side are used to connect with an external photovoltaic device.

[0036] In this embodiment, specifically, the three-phase interface for AC measurement comprises an A-phase interface 411, a B-phase interface 412, and a C-phase interface 413; and the positive and negative interfaces on the DC side comprise a positive interface 421 and a negative interface 422.

[0037] In the embodiment, specifically, the converter comprises a DC / DC converter and a DC / AC inverter; part of the electric energy input by the external photovoltaic device is output to the 10kV three-phase alternating current microgrid through the DC / DC converter and the DC / AC inverter, and another part of the electric energy is stored in the lithium battery pack 22 and the super capacitor pack 23 through the DC / DC converter, and the electric energy stored in the lithium battery pack 22 and the super capacitor pack 23 can be output to the 10kV three-phase alternating current microgrid through the DC / DC converter and the DC / AC inverter.

[0038] In the embodiment, specifically, the converter further comprises a 25kV DC bus 211.

[0039] The DC / DC converter comprises three DC / DC converters, namely a first DC / DC converter, a second DC / DC converter and a third DC / DC converter; one end of the first DC / DC converter is connected with the external photovoltaic device through the junction box 4, and the other end of the first DC / DC converter is connected with the 25kV DC bus 211; one end of the second DC / DC converter is connected with the 25kV DC bus 211, and the other end of the second DC / DC converter is connected with the lithium battery pack 22; one end of the third DC / DC converter is connected with the 25kV DC bus 211, and the other end of the third DC / DC converter is connected with the super capacitor pack 23.

[0040] In the embodiment, specifically, the lithium battery pack 22 is connected with the bottom of the electrical cabinet box 1 through the first support column 121 and the second support column 122, and the super capacitor pack 23 is located on the upper side of the lithium battery pack 22.

[0041] In the embodiment, specifically, the front of the electrical cabinet box 1 is provided with an electrical cabinet door 12.

[0042] In the embodiment, specifically, the electrical cabinet box 1 is further provided with a heat dissipation device 3.

[0043] In the embodiment, specifically, the heat dissipation device 3 comprises a heat dissipation air duct 111 arranged inside the electrical cabinet box 1, an air outlet 113 arranged above the electrical cabinet box 1, and an air inlet 112 arranged below the electrical cabinet box 1; one end of the heat dissipation air duct 111 is connected with the air inlet 112, and the other end of the heat dissipation air duct 111 is connected with the air outlet 113.

[0044] In the embodiment, specifically, the air inlet 112 is provided with a heat dissipation fan 31, and the air outlet 113 is provided with a heat dissipation grille 32; the heat dissipation fan 31 carries away the heat generated by the energy storage assembly 2 through the heat dissipation air duct 111, the air outlet 113 and the heat dissipation grille 32, thereby playing a heat dissipation role.

[0045] It should be noted that the specific working process of the utility model is as follows:

[0046] The external photovoltaic device starts generating electricity under suitable lighting conditions and is connected to the converter inside the electrical cabinet box 1 through the positive interface 421 and the negative interface 422 on the junction box 4. The converter converts low-voltage direct current into 25kV direct current through the internal DC\DC converter, and then connects to the 25kV direct current bus 211. Part of the electric energy is directly supplied to the 10kV three-phase alternating current microgrid through the DC\AC inverter inside the converter, meeting its immediate power demand. Another part of the electric energy is distributed to the energy storage assembly 2 for storage.

[0047] The battery pack is responsible for long-term energy storage, which enables the device to cope with long-term power demand. At the same time, the super capacitor group 23 is responsible for short-term energy storage and has the characteristics of fast charging and discharging, so it can quickly release the stored electric energy to meet the sudden load demand.

[0048] The DC\DC converter inside the converter dynamically adjusts the electric energy output of the lithium battery group 22 and the super capacitor group 23 inside the energy storage assembly 2 according to the real-time demand of the microgrid. This can ensure that the microgrid can quickly obtain the required electric energy when facing sudden load demand, while balancing the supply and demand of the microgrid.

[0049] The cooling fan 31 is controlled according to the temperature in the air distribution duct, and the generated heat is discharged through the air outlet 113 and the cooling grille 32 to ensure that the device maintains a normal operating temperature during operation. This helps to improve the stability and reliability of the system, avoids failures caused by overheating, and prolongs the service life of the device.

[0050] Finally, the 25kV direct current bus 211 converts direct current into alternating current through the DC / AC inverter, and then connects to the 10kV, 50Hz three-phase alternating current microgrid to meet the power demand of the microgrid. Through such a working process, the device can effectively utilize the electric energy generated by the photovoltaic power generation system, and combine the hybrid energy storage technology of batteries and super capacitors to improve energy utilization efficiency, cope with daily and sudden energy fluctuations, and use the cooling assembly 3 to promptly remove heat, thereby enhancing the stability and reliability of the microgrid.

[0051] The above-described embodiments only express the specific implementation of the present application, which is described in detail and specifically, but it cannot be understood as a limitation on the protection scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the technical concept of the present application, a number of modifications and improvements can be made, which are within the protection scope of the present application.

[0052] This Background section is intended to introduce the current application and provide basic context for the application. The preceding description of background art may be included to further provide context for the current application, and to assist with understanding the current application. However, any recognition that this section may be construed as prior art is not intended, and should not be inferred.

Claims

1. A photovoltaic micro-grid power device with lithium battery hybrid supercapacitor energy storage, characterized in that, include: An electrical cabinet enclosure (1) is provided with a junction box (4) on the rear side of the electrical cabinet enclosure (1), and a converter and an energy storage component (2) are provided inside the electrical cabinet enclosure (1). The energy storage component (2) includes: a lithium battery pack (22) and a supercapacitor pack (23); One end of the converter is connected to an external photovoltaic device through a junction box (4); the other end of the converter is connected to a lithium battery pack (22) and a supercapacitor pack (23) on one side, and to the power grid through a junction box (4) on the other side. The converter includes a DC / DC converter and a DC / AC inverter. Part of the electrical energy input from the external photovoltaic device is output to the 10kV three-phase AC microgrid through the DC / DC converter and the DC / AC inverter, and another part of the electrical energy is stored in the lithium battery pack (22) and the supercapacitor pack (23) through the DC / DC converter. At the same time, the electrical energy stored in the lithium battery pack (22) and the supercapacitor pack (23) can be output to the 10kV three-phase AC microgrid through the DC / DC converter and the DC / AC inverter. The converter also includes: a 25kV DC bus (211); There are three DC / DC converters: a first DC / DC converter, a second DC / DC converter, and a third DC / DC converter. One end of the first DC / DC converter is connected to an external photovoltaic device through a junction box (4), and the other end of the first DC / DC converter is connected to a 25kV DC bus (211). One end of the second DC / DC converter is connected to a 25kV DC bus (211), and the other end of the second DC / DC converter is connected to a lithium battery pack (22). One end of the third DC / DC converter is connected to a 25kV DC bus (211), and the other end of the third DC / DC converter is connected to a supercapacitor pack (23).

2. The photovoltaic microgrid power supply device of claim 1, wherein, The junction box (4) includes: a three-phase AC interface, a positive and negative DC interface, and a chassis grounding interface (423); the three-phase AC interface is used to connect to a 10kV three-phase AC microgrid, and the positive and negative DC interface is used to connect to an external photovoltaic device.

3. The photovoltaic micro-grid power supply device of claim 2, wherein, The three-phase interface of the AC side includes: phase A interface (411), phase B interface (412) and phase C interface (413); the positive and negative interfaces of the DC side include: positive interface (421) and negative interface (422).

4. The photovoltaic micro-grid power supply device of claim 3, wherein, The lithium battery pack (22) is connected to the bottom of the electrical cabinet box (1) through the first support column (121) and the second support column (122), and the supercapacitor pack (23) is located on the upper side of the lithium battery pack (22).

5. The photovoltaic microgrid power supply device of claim 4, wherein, The electrical cabinet enclosure (1) has an electrical cabinet door (12) on the front.

6. The photovoltaic microgrid power supply device of claim 5, wherein, The electrical cabinet (1) is also equipped with a heat dissipation device (3).

7. The photovoltaic micro-grid power supply device of claim 6, wherein, The heat dissipation device (3) comprises a heat dissipation air duct (111) arranged inside the electrical cabinet box body (1), an air outlet (113) arranged above the electrical cabinet box body (1), and an air inlet (112) arranged below the electrical cabinet box body (1); one end of the heat dissipation air duct (111) is connected with the air inlet (112), and the other end is connected with the air outlet (113).

8. The photovoltaic micro-grid power supply device of claim 7, wherein, A heat dissipation fan (31) is arranged on the air inlet (112); and a heat dissipation grille (32) is arranged on the air outlet (113).

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