Flexible interconnection system for low-voltage transformer area
By adding variable charging piles in the up and down directions of highway service areas and using switching switches and relays to coordinate power consumption, the problem of unbalanced power consumption has been solved, and a balanced distribution of power and improved reliability have been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CCCC PHOTOVOLTAIC TECH CO LTD
- Filing Date
- 2025-05-30
- Publication Date
- 2026-05-12
AI Technical Summary
At the same location in a highway service area, the electricity consumption of the two service areas is unbalanced, resulting in the photovoltaic power generation devices generating the same total amount of electricity but with asymmetrical electricity consumption, causing energy loss.
Variable charging piles are added to the up and down sections of highway service areas, and the power input source is switched by switching switches to achieve power coordination and balance, and reliable switching control is achieved by using relays.
It reduced investment costs, improved power utilization, achieved a balanced distribution of power, and enhanced system reliability.
Smart Images
Figure CN224233343U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to photovoltaic application systems, and in particular to a flexible interconnection system for low-voltage distribution areas. Background Technology
[0002] With the increasing global demand for renewable energy, distributed intermittent energy sources such as solar power are gradually becoming an important part of the power system. This transformation places higher demands on the flexibility and adaptability of the power grid. On the other hand, with the increasing popularity of electric vehicles, the volatility of loads is increasing, exacerbating the impact on the power grid.
[0003] In response, some people skilled in the art have proposed installing photovoltaic (PV) power generation systems in highway service areas. These PV systems, along with the associated loads, form a microgrid. Energy storage devices are used to regulate the microgrid's internal processes. Specifically, the PV power is first used to supply the loads, then to power charging stations, and finally to charge batteries. Any remaining electricity is sold back to the grid. Conversely, when the PV output is insufficient to meet load demand, the batteries will release electricity to supplement the load; when the batteries are also low on power, the grid will provide the necessary surplus electricity.
[0004] However, most highway service areas currently adopt a side-island layout to reduce toll management costs. Specifically, a service area is located at the same point on both sides of the highway, and the two service areas are not interconnected. This leads to a problem: during the beginning and end of holidays, the traffic flow in the two directions of the highway is significantly asymmetrical, resulting in an imbalance in electricity consumption. However, the photovoltaic power generation devices of both service areas are geographically close and their total power generation is relatively consistent. In the current technology, as independent microgrids, they can only interact with the grid separately, which undoubtedly causes greater energy loss. Utility Model Content
[0005] The purpose of this invention is to provide a flexible interconnection system for low-voltage distribution areas.
[0006] The objective of this utility model can be achieved through the following technical solutions:
[0007] A low-voltage distribution area flexible interconnection system includes a first microgrid and a second microgrid. The first microgrid is located in the upstream area of any service area of a highway, and the second microgrid is located in the downstream area of the same service area of the highway. The first microgrid includes a first photovoltaic power generation module, a first substation, a first fixed charging pile, and a first load. The output terminal of the first photovoltaic power generation module is connected to the first load and the first fixed charging pile via the first substation. The second microgrid includes a second photovoltaic power generation module, a second substation, a second fixed charging pile, and a second load. The output terminal of the second photovoltaic power generation module is connected to the second load and the second fixed charging pile via the second substation. The first microgrid also includes a first variable charging pile and a first switching switch. The second microgrid includes a second variable charging pile and a second switching switch. The power input terminal of the first variable charging pile is selectively connected to either the first substation or the second substation via the first switching switch, and the power input terminal of the second variable charging pile is selectively connected to either the second substation or the first substation via the second switching switch.
[0008] Both the first and second switching switches are single-pole double-throw switches. The common terminal of the first switching switch is connected to the power input terminal of the first variable charging pile, the normally closed terminal is connected to the first substation, and the normally open terminal is connected to the second substation. The common terminal of the second switching switch is connected to the power input terminal of the second variable charging pile, the normally closed terminal is connected to the second substation, and the normally open terminal is connected to the first substation.
[0009] The single-pole double-throw switch is a relay.
[0010] The system also includes a controller for controlling whether the relay is engaged or not. The first output pin of the controller is connected to the coil of the first switching switch, and the second output pin is connected to the coil of the second switching switch. When the output pin outputs a high level, the coil is turned on.
[0011] The controller is a microcontroller.
[0012] The first and second transformers have the same structure.
[0013] The first power conversion device includes an inverter and a transformer.
[0014] The first microgrid also includes a first energy storage battery, and the second microgrid also includes a second energy storage battery.
[0015] Both the first and second energy storage batteries are lithium batteries.
[0016] Both the first and second switching switches are manual switches.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] 1. By adding a first variable charging pile and a second variable charging pile in the up and down areas of the same service area, and switching their power input sources through a first switching switch and a second switching switch, on the one hand, the power of the two areas that are already complementary in load can be coordinated to form a offset, thereby reducing investment costs. On the other hand, power balancing is achieved through switching switches and charging piles, without the need for complex software and hardware control, resulting in higher reliability.
[0019] 2. Using relays for switching results in higher reliability and lower cost.
[0020] 3. By setting up energy storage devices, excess energy during the day can be stored, improving the utilization rate of electrical energy. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the structure of this utility model;
[0022] Figure 2 This is a schematic diagram of the primary loop of the control section;
[0023] Figure 3 This is a schematic diagram of the secondary circuit of the control section;
[0024] Wherein: 1. First microgrid, 2. Second microgrid, 1-1. First photovoltaic power generation module, 1-2. First substation, 1-3. First fixed charging pile, 1-4. First load, 1-5. First variable charging pile, 2-1. Second photovoltaic power generation module, 2-2. Second substation, 2-3. Second fixed charging pile, 2-4. Second load, 2-5. Second variable charging pile, K1. First switching switch, K2. Second switching switch. Detailed Implementation
[0025] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.
[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0027] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. Furthermore, the terms "proximal end," "farthest end," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Physical quantities in formulas, unless otherwise specified, should be understood as basic quantities of the International System of Units (SI) base units, or derived quantities derived from basic quantities through mathematical operations such as multiplication, division, differentiation, or integration.
[0028] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0029] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0030] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0031] A flexible interconnection system for low-voltage distribution areas, such as Figure 1As shown, the system includes a first microgrid 1 and a second microgrid 2. The first microgrid 1 is located in the upstream area of any service area on the highway, and the second microgrid 2 is located in the downstream area of the same service area on the highway. The first microgrid 1 includes a first photovoltaic power generation module 1-1, a first transformer 1-2, a first fixed charging pile 1-3, and a first load 1-4. The output of the first photovoltaic power generation module 1-1 is connected to the first load 1-4 and the first fixed charging pile 1-3 via the first transformer 1-2. The second microgrid 2 includes a second photovoltaic power generation module 2-1, a second transformer 2-2, a second fixed charging pile 2-3, and a second load 2-4. The output of the second photovoltaic power generation module 2-1 is connected to the second load 2-4 and the second fixed charging pile 2-3 via the second transformer 2-2. The first microgrid 1 also includes a first variable charging pile 1-5 and a first switching switch K1. The second microgrid 2 includes a second variable charging pile 2-5 and a second switching switch K2. Figure 2 As shown, the power input terminal of the first variable charging pile 1-5 is selectively connected to either the first transformer 1-2 or the second transformer 2-2 via the first switching switch K1, and the power input terminal of the second variable charging pile 2-5 is selectively connected to either the second transformer 2-2 or the first transformer 1-2 via the second switching switch K2.
[0032] By adding a first variable charging pile 1-5 and a second variable charging pile 2-5 to the up and down areas of the same service area, and switching their power input sources through the first switching switch K1 and the second switching switch K2, on the one hand, the power of the two areas that are already complementary in load can be coordinated to form a offset, thereby reducing investment costs. On the other hand, power balancing is achieved through switching switches and charging piles, without the need for complex software and hardware control, resulting in higher reliability.
[0033] In most embodiments, both the first switching switch K1 and the second switching switch K2 are single-pole double-throw switches. The common terminal of the first switching switch K1 is connected to the power input terminal of the first variable charging pile 1-5, the normally closed terminal is connected to the first transformer 1-2, and the normally open terminal is connected to the second transformer 2-2. Similarly, the common terminal of the second switching switch K2 is connected to the power input terminal of the second variable charging pile 2-5, the normally closed terminal is connected to the second transformer 2-2, and the normally open terminal is connected to the first transformer 1-2. This configuration allows for the retention of a scheme where the first variable charging pile 1-5 is powered by the first photovoltaic power generation module 1-1 and the second variable charging pile 2-5 is powered by the second photovoltaic power generation module 2-1. Of course, in other embodiments, ... The first switching switch K1 and the second switching switch K2 can be integrated into a double-pole double-throw switch, thereby enabling the first variable charging pile 1-5 and the second variable charging pile 2-5 to switch between being simultaneously powered by the first photovoltaic power generation module 1-1 and simultaneously powered by the second photovoltaic power generation module 2-1. Specifically, the wiring connection scheme can be as follows: the two contacts of the common terminal of the double-pole double-throw switch are respectively connected to the power input terminals of the first variable charging pile 1-5 and the second variable charging pile 2-5; the two normally open contacts are each connected to one of the first transformer 1-2 and the second transformer 2-2; and the two normally closed contacts are each connected to the other of the first transformer 1-2 and the second transformer 2-2.
[0034] In most embodiments that use single-pole double-throw switches, the single-pole double-throw switch is a relay. Switching is performed using a relay, which results in higher reliability and lower cost.
[0035] Furthermore, in some embodiments, the system also includes a controller for controlling whether the relay is engaged or not. The controller's first output pin is connected to the coil of the first switching switch K1, and its second output pin is connected to the coil of the second switching switch K2. When the output pin is high, the coil is activated. Generally, the controller can be a microcontroller, such as... Figure 3 As shown, O1.1 and O1.2 represent the first output pin and the second output pin, respectively.
[0036] In addition, the controller's actions can be timed, that is, the switching time is pre-configured. Of course, in some embodiments, other methods can also be used, such as using indicators such as traffic flow detection, power and charging pile occupancy rate to achieve automatic control.
[0037] In almost all embodiments, the first power transformer 1-2 and the second power transformer 2-2 have the same structure. Specifically, the first power transformer 1-2 includes an inverter and a transformer. The transformer outputs AC power of about 380V or 1KV, depending on the site conditions.
[0038] Generally, the first microgrid 1 also includes a first energy storage battery, and the second microgrid 2 also includes a second energy storage battery. Both the first and second energy storage batteries are lithium batteries with appropriate capacity, such as around 300 kWh.
[0039] Of course, in some embodiments, both the first switching switch K1 and the second switching switch K2 are manual switches, which are switched manually during holidays. For example, for the G60 expressway, the upstream direction is from west to east and the downstream direction is from east to west. On the first day of the holiday, the downstream traffic flow is large. Therefore, the power generation of the first microgrid 1 is excessive, and the second variable charging pile 2-5 needs to be switched to be powered by the first transformer 1-2 of the first microgrid 1. Conversely, on the last day of the holiday, the upstream traffic flow is large. Therefore, the power generation of the second microgrid 2 is excessive, and the first variable charging pile 1-5 needs to be switched to be powered by the first transformer 1-2 of the second microgrid 2.
Claims
1. A low-voltage distribution area flexible interconnection system, comprising a first microgrid and a second microgrid, wherein the first microgrid is arranged in the upstream area of any service area of a highway, and the second microgrid is arranged in the downstream area of the same service area of the highway, the first microgrid comprising a first photovoltaic power generation module, a first substation, a first fixed charging pile, and a first load, wherein the output terminal of the first photovoltaic power generation module is connected to the first load and the first fixed charging pile respectively via the first substation, and the second microgrid comprising a second photovoltaic power generation module, a second substation, a second fixed charging pile, and a second load, wherein the output terminal of the second photovoltaic power generation module is connected to the second load and the second fixed charging pile respectively via the second substation, characterized in that, The first microgrid also includes a first variable charging pile and a first switching switch. The second microgrid includes a second variable charging pile and a second switching switch. The power input terminal of the first variable charging pile is selectively connected to either the first substation or the second substation through the first switching switch. The power input terminal of the second variable charging pile is selectively connected to either the second substation or the first substation through the second switching switch.
2. The low-voltage distribution area flexible interconnection system according to claim 1, characterized in that, Both the first and second switching switches are single-pole double-throw switches. The common terminal of the first switching switch is connected to the power input terminal of the first variable charging pile, the normally closed terminal is connected to the first substation, and the normally open terminal is connected to the second substation. The common terminal of the second switching switch is connected to the power input terminal of the second variable charging pile, the normally closed terminal is connected to the second substation, and the normally open terminal is connected to the first substation.
3. The low-voltage distribution area flexible interconnection system according to claim 2, characterized in that, The single-pole double-throw switch is a relay.
4. A low-voltage distribution area flexible interconnection system according to claim 3, characterized in that, The system also includes a controller for controlling whether the relay is engaged or not. The first output pin of the controller is connected to the coil of the first switching switch, and the second output pin is connected to the coil of the second switching switch. When the output pin outputs a high level, the coil is turned on.
5. A low-voltage distribution area flexible interconnection system according to claim 4, characterized in that, The controller is a microcontroller.
6. A low-voltage distribution area flexible interconnection system according to claim 1, characterized in that, The first and second transformers have the same structure.
7. A low-voltage distribution area flexible interconnection system according to claim 6, characterized in that, The first power conversion device includes an inverter and a transformer.
8. A low-voltage distribution area flexible interconnection system according to claim 1, characterized in that, The first microgrid also includes a first energy storage battery, and the second microgrid also includes a second energy storage battery.
9. A low-voltage distribution area flexible interconnection system according to claim 8, characterized in that, Both the first and second energy storage batteries are lithium batteries.
10. A low-voltage distribution area flexible interconnection system according to claim 1, characterized in that, Both the first and second switching switches are manual switches.