Power distribution and utilization system for converting middle-high voltage three-phase alternating current transmission into low-voltage direct current power supply

Abstract

The invention relates to a medium-high voltage three-phase alternating current power transmission to low-voltage direct current power supply and distribution power utilization system, and aims to improve the energy utilization efficiency, avoid imbalance of low-voltage three-phase power utilization, enhance the stability and safety of a power grid, improve the flexibility and expandability of power distribution, and realize intelligent management, energy conservation and consumption reduction. The system mainly comprises a three-phase rectification power distribution device, a 310V direct-current power supply facility, a direct-current power distribution facility, a power taking facility, a power utilization facility and a multi-power-supply grid-connected device. According to the system, electric energy output by the middle-high voltage transformer is converted into 310V direct current through the three-phase rectifier, two-wire power supply is achieved, traditional alternating current two-wire system, three-phase four-wire system and three-phase five-wire system power supply modes are replaced, investment of electric power construction is reduced, and power supply energy loss is reduced; grid-connected power supply of various power supplies (energy sources) is facilitated, and efficient utilization of the energy sources is realized. The power transmission cost is reduced; and the operation power factor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power supply, and in particular to a medium- and high-voltage three-phase alternating current transmission to low-voltage direct current power supply and distribution system. Background Art

[0002] In traditional power supply systems, alternating current (AC) is the main form of power transmission and distribution. In order to meet the needs of different voltage levels and electrical equipment, transformers are usually required to transform and isolate the voltage to ensure the safety and stability of power transmission. However, with the continuous development of power electronics technology and the transformation of energy structure, traditional AC power supply systems are facing some challenges.

[0003] First of all, the current low-voltage power supply adopts a three-phase four-wire system, and the household generally adopts a two-wire AC 220V voltage. In order to ensure the balance of three-phase electricity consumption, the user generally adopts a dispersed phase hanging method. However, due to the serious differences in the power consumption of users, the problem of unbalanced three-phase electricity consumption has always been caused. With the increasing maturity of AC-DC conversion technology, all household appliances can achieve efficient voltage conversion with secondary power supply transformation technology, such as microcomputers, televisions, various chargers, induction cookers, etc. The working principle of the secondary power supply is to first rectify the 220V AC into 310V DC and then use high-frequency switches to rectify and filter into various required DC voltages. That is to say, the use of AC 220V and DC 310V for household appliances is equivalent. In order to solve this problem, the use of 310V AC after three-phase bridge rectification can ensure the balance of three-phase electricity consumption.

[0004] Secondly, with the rapid development of various power supply energy sources, the demand for grid connection of renewable energy sources such as wind power and solar power is increasing. However, these various power supply energy sources are often generated in the form of direct current (DC) and need to be converted before they can be connected to the traditional AC power grid. This process not only increases the complexity and cost of energy conversion, but may also affect the stability of the power grid.

[0005] Therefore, the present invention proposes a new type of DC household access system, which achieves the goals of efficient energy utilization, improved stability and security of the power grid, enhanced flexibility and scalability of power distribution, and intelligent management and energy conservation and emission reduction by adopting efficient three-phase rectifier distribution devices and ferrite transformers. Summary of the invention

[0006] In order to solve the problems of the prior art, the present invention provides a medium- and high-voltage three-phase AC power transmission to low-voltage DC power supply and distribution system. This system not only solves the problems existing in the traditional AC power supply system, but also provides strong support for building a green, low-carbon and sustainable energy system.

[0007] In order to solve the above technical problems, the present invention is implemented by the following technical solutions: a medium- and high-voltage three-phase AC power transmission to low-voltage DC power supply and distribution power system, characterized in that it includes:

[0008] Three-phase rectifier and distribution device, used to convert the input AC220V three-phase alternating current into 310V direct current distribution, and output transmission through branch lines;

[0009] The user transformer is used to convert the input medium and high voltage three-phase AC power into three-phase AC power with a line voltage of 220V, and is electrically connected to the input end of the three-phase rectifier and distribution device through a low-voltage three-phase line. The input end of the user transformer is electrically connected to the output end of the substation through a high-voltage three-phase line;

[0010] A variety of power supply energy grid-connected devices, for output 310V DC, are connected to the grid through constant voltage parallel connection.

[0011] In this embodiment, the substation outputs medium and high voltage three-phase alternating current.

[0012] The input end of the user transformer is electrically connected to the output end of the substation through a high-voltage three-phase line to receive this high-voltage three-phase alternating current.

[0013] Voltage conversion (user transformer):

[0014] The user transformer converts the input medium and high voltage three-phase AC power into 220V three-phase AC power.

[0015] The converted line voltage 220V three-phase alternating current is electrically connected to the input end of the three-phase rectification and distribution device through a low-voltage three-phase line.

[0016] Conversion of three-phase AC to DC (three-phase rectifier and distribution device):

[0017] The three-phase rectifier and distribution device receives 220V three-phase AC power from the user's transformer.

[0018] The device converts three-phase AC power into 310V DC power.

[0019] The converted 310V DC power is output and transmitted through branch lines for subsequent use.

[0020] Integration of multiple power supply energy devices (optional step):

[0021] If there are multiple power supply energy devices (such as solar power generation, wind power generation, etc.) output 310V DC.

[0022] The direct current generated by these various power supply energy devices can be electrically connected to the three-phase rectifier and distribution device through a high-voltage branch line, and integrated or backed up with the direct current output by the rectifier device.

[0023] In a specific implementation, the branch lines are arranged in multiple groups, and each group of branch lines may be provided with multiple groups of household branch lines with parallel outputs, so as to achieve flexibility and scalability of power distribution and meet the power demand of different users;

[0024] When multiple groups of users need to access electricity, the corresponding household branch lines can be connected in parallel to the branch lines to achieve power distribution. Due to the characteristics of the parallel circuit, each group of household branch lines can obtain the same voltage, and the current can be divided according to their respective load requirements to meet the power needs of different users. Through multiple groups of household branch lines with parallel output, power distribution can be flexibly adjusted according to actual power demand. When a user needs to increase the power supply, just connect the corresponding household branch line in parallel to the branch line.

[0025] In a specific implementation, the multiple power supply energy grid-connected devices include but are not limited to wind energy, solar energy, hydropower and tidal energy, batteries, and oil-powered generators. The power output specification of the multiple power supply energy grid-connected devices is AC220V or 310V direct current, which is directly connected to the distribution box;

[0026] The electricity generated by the various power supply energy devices (which may be AC ​​or DC, and the voltage and current may vary) is first processed by their respective power conversion systems.

[0027] The power conversion system usually includes components such as rectifiers, inverters, and transformers, which are used to convert raw electricity into 310V DC power that meets the requirements.

[0028] The converted direct current is connected to the main power system through high-voltage branches to achieve parallel operation with the power grid.

[0029] In a specific embodiment, the three-phase rectifier and distribution device is internally integrated with safety mechanisms including but not limited to overvoltage protection, overcurrent protection and short-circuit protection to ensure the stability and safety of the rectification process;

[0030] The overvoltage, overcurrent and short-circuit protection mechanisms can detect and handle abnormal situations in a timely manner, preventing the power electronic devices inside the rectifier from being damaged due to overvoltage, overcurrent or short circuit.

[0031] In a specific implementation, it further includes an energy management algorithm, which can dynamically adjust the output voltage and current of the three-phase rectifier and distribution device according to the grid load, the input of the clean energy device and the power demand of the user, so as to achieve the optimal configuration and efficient utilization of energy;

[0032] By dynamically adjusting the output of the three-phase rectifier and distribution device, the energy management algorithm can ensure the balance between power supply and demand, reduce energy waste, and improve the utilization efficiency of multiple power supply energy sources;

[0033] The algorithm can monitor the grid load and various power supply energy inputs in real time, and adjust the power output in time to cope with grid fluctuations and emergencies, thereby enhancing the stability and reliability of the grid.

[0034] In a specific embodiment, it further includes the formulation of DC310V metering instruments, switches, plugs, and socket standards, which are different from AC 220V power distribution and electrical appliances, and provide adapters for AC220V and DC310V universal electrical appliances.

[0035] The beneficial effects of the present invention are:

[0036] 1. The present invention efficiently converts AC 220V into DC 310V through a three-phase rectifier and distribution device, which reduces the energy loss in the AC-DC conversion process and improves the energy utilization efficiency. The ferrite transformer is used to adjust the DC voltage. Compared with the traditional 50Hz transformer, it is smaller in size and lighter in weight, further reducing the energy loss in the transmission process, while reducing material consumption and manufacturing costs;

[0037] 2. The DC household system reduces AC fluctuations in the power grid, making the power supply more stable, which is conducive to protecting the stable operation of electrical equipment. DC voltage has advantages over AC voltage in terms of electric shock safety, because DC current is not easy to cause ventricular fibrillation, reducing the risk of electric shock. At the same time, the three-phase rectifier and distribution device in the present invention integrates multiple safety protection mechanisms, such as overvoltage protection, overcurrent protection and short-circuit protection, which further improves the safety of the system;

[0038] 3. The various power supply energy devices in the invention are converted into 310V DC power through their own power conversion systems and connected to the power grid, thus achieving efficient grid connection and utilization of various power supply energy sources, and providing strong support for building a green and low-carbon energy system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the system structure of the present invention.

[0040] Figure 2 It is a physical connection schematic diagram of the present invention.

[0041] Figure 3 It is a schematic diagram of an adapter for AC220V and DC310V universal electrical appliances of the present invention.

[0042] Figures 1 to 3In: 1. Substation; 11. High-voltage three-phase electricity; 2. User transformer; 21. Low-voltage three-phase electricity; 3. Three-phase rectifier and distribution device; 31. 310V DC main branch line; 311. Household branch line; 4. Clean energy device; 41. 310V DC incorporated branch line. DETAILED DESCRIPTION

[0043] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0044] Embodiment 1: Figures 1 to 3 The medium- and high-voltage three-phase AC transmission to low-voltage DC power supply and distribution system shown includes: a three-phase rectifier and distribution device for converting the input AC220V three-phase AC power into 310V DC power distribution, and outputting it through a branch line for transmission; a user transformer for converting the input medium- and high-voltage three-phase AC power into three-phase AC power with a line voltage of 220V, which is electrically connected to the input end of the three-phase rectifier and distribution device through a low-voltage three-phase line, and the input end of the user transformer is electrically connected to the output end of the substation through a high-voltage three-phase line; a multi-power supply energy grid-connected device, which is connected to the grid through a constant voltage parallel connection method for the output 310V DC power.

[0045] The branch lines are arranged in multiple groups, and each group of branch lines can be provided with multiple groups of household branch lines with parallel outputs, so as to realize the flexibility and scalability of power distribution and meet the power needs of different users. The various power supply energy grid-connected devices include but are not limited to wind energy, solar energy, hydropower and tidal energy, batteries, and oil generators. The power output specification of the various power supply energy grid-connected devices is AC220V or 310V direct current, which is directly connected to the distribution box. The three-phase rectifier distribution device is internally integrated with safety mechanisms including but not limited to overvoltage protection, overcurrent protection and short-circuit protection to ensure the stability and safety of the rectification process.

[0046] Further, it includes the formulation of standards for DC310V meters, switches, plugs and sockets, which are different from AC 220V power distribution and electrical appliances, and provides adapters for electrical appliances that are common to AC220V and DC310V.

[0047] In this embodiment: three-phase rectifier and power distribution device:

[0048] Function: Efficiently convert the input 220V three-phase AC power into 310V DC power and distribute it to meet the needs of specific electrical equipment.

[0049] Features: Multiple safety mechanisms such as overvoltage protection, overcurrent protection and short-circuit protection are integrated to ensure the stability and safety of the rectification process. These safety mechanisms can monitor parameters such as voltage and current in real time. Once an abnormal situation is detected, protective measures will be taken immediately to prevent equipment damage or safety accidents.

[0050] User transformer:

[0051] Function: Convert the 380V standard three-phase AC power of the city electricity into 220V three-phase AC power, and provide the three-phase rectifier with power equivalent to AC220V household power.

[0052] Connection method: The output end of the mains transformer is regulated to a line voltage of AC220V and connected to the distribution box, where it is rectified into DC310V and then transmitted to each user via two lines.

[0053] Multi-energy direct grid-connected device:

[0054] Type: including but not limited to wind energy, solar energy, hydropower and tidal energy, batteries, and oil-generator generators connected to the grid in a DC constant voltage parallel manner. Simple, reliable and stable. Convenient for charging piles and other high current loads to be connected.

[0055] Embodiment 2: It further includes an energy management algorithm, which can dynamically adjust the output voltage and current of the three-phase rectifier device according to the grid load, the input conditions of various power supply energy devices and the user's electricity demand, so as to achieve optimal configuration and efficient utilization of energy.

[0056] Power distribution system:

[0057] Branch line setting: The system is set up with multiple branches, each of which can output multiple sets of household branches in parallel. This design improves the flexibility and scalability of power distribution and can meet the power needs of different users.

[0058] Intelligent management: Through smart meters and distribution management systems, power usage can be monitored in real time, power distribution can be optimized, and energy efficiency can be improved.

[0059] In this embodiment: Energy management algorithm:

[0060] Function: Dynamically adjust the output voltage and current of the three-phase rectifier according to the grid load, the input of various energy devices and the user's electricity demand.

[0061] Implementation method: Through real-time monitoring and analysis of power grid data, power generation data of various power supply energy sources, and user power consumption data, the algorithm calculates the optimal power output strategy and controls the three-phase rectifier device to make corresponding adjustments.

[0062] Algorithm advantages:

[0063] Improve energy efficiency: By dynamically adjusting power output, ensure the balance between power supply and demand and reduce energy waste.

[0064] Enhance grid stability: The algorithm can monitor grid load and multiple power supply energy inputs in real time, and adjust power output in a timely manner to cope with grid fluctuations and emergencies.

[0065] Optimize user experience: Based on the user's electricity demand, the algorithm can intelligently adjust the power output to ensure that users have a stable and reliable power supply.

[0066] System scalability:

[0067] With the continuous development of various power supply energy sources and the continuous changes in user electricity demand, the system can further improve energy utilization efficiency and the flexibility of power distribution by upgrading algorithms and optimizing hardware configuration.

[0068] At the same time, the system can also be combined with other smart grid technologies, such as energy storage technology, demand response technology, etc., to jointly build a more efficient and intelligent power supply system.

[0069] In summary, the first embodiment and the second embodiment together constitute an efficient, intelligent, and scalable high-voltage three-phase AC power transformation system that converts three-phase AC power with a line voltage of AC220 into DC310V DC power supply and distribution. The system not only improves energy utilization efficiency, but also enhances the stability and reliability of the power grid, providing users with better quality power services.

[0070] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A medium- and high-voltage three-phase AC transmission system that converts to low-voltage DC power supply and distribution, characterized in that: include: Three-phase rectifier and distribution device, used to convert the input AC220V three-phase alternating current into 310V direct current distribution, and output transmission through branch lines; The user transformer is used to convert the input medium and high voltage three-phase AC power into three-phase AC power with a line voltage of 220V, and is electrically connected to the input end of the three-phase rectifier and distribution device through a low-voltage three-phase line. The input end of the user transformer is electrically connected to the output end of the substation through a high-voltage three-phase line; A variety of power supply energy grid-connected devices, for output 310V DC, are connected to the grid through constant voltage parallel connection.

2. The medium- and high-voltage three-phase AC power transmission to low-voltage DC power supply and distribution system according to claim 1 is characterized in that: The branch lines are arranged in multiple groups, and each group of branch lines can be provided with multiple groups of household branch lines with parallel outputs, so as to achieve flexibility and scalability of power distribution and meet the power needs of different users.

3. The medium- and high-voltage three-phase AC power transmission to low-voltage DC power supply and distribution system according to claim 1 is characterized in that: The various power supply energy grid-connected devices include but are not limited to wind energy, solar energy, hydropower and tidal energy, batteries, and oil generators. The power output specification of the various power supply energy grid-connected devices is AC220V or 310V direct current, which is directly connected to the distribution box.

4. The medium- and high-voltage three-phase AC power transmission to low-voltage DC power supply and distribution system according to claim 1 is characterized in that: The three-phase rectification and distribution device has integrated safety mechanisms including but not limited to overvoltage protection, overcurrent protection and short-circuit protection to ensure the stability and safety of the rectification process.

5. The medium- and high-voltage three-phase AC power transmission to low-voltage DC power supply and distribution system according to claim 1 is characterized in that: Furthermore, it also includes an energy management algorithm, which can dynamically adjust the output voltage and current of the three-phase rectifier and distribution device according to the grid load, the input of the clean energy device and the user's electricity demand, so as to achieve the optimal configuration and efficient use of energy.

6. The medium- and high-voltage three-phase AC power transmission to low-voltage DC power supply and distribution system according to claim 1 is characterized in that: Further, it includes the formulation of standards for DC310V meters, switches, plugs and sockets, which are different from AC 220V power distribution and electrical appliances, and provides adapters for electrical appliances that are common to AC220V and DC310V.

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