Alternating current and direct current interconnected micro power system based on same power transmission cable

Abstract

The invention discloses an alternating current and direct current interconnected micro power system based on the same power transmission cable, and relates to the technical field of power generation and transmission and distribution of power systems. A direct-current power generation device of the system converts direct current into alternating current through an inversion device and then accesses an alternating-current and direct-current power transmission cable, or accesses the direct current into the alternating-current and direct-current power transmission cable through a direct-current adjusting device; the alternating current power generation device converts alternating current into direct current through the rectifying device and then accesses the direct current to the alternating current and direct current transmission cable, or accesses the alternating current to the alternating current and direct current transmission cable through the alternating current adjusting device. The AC / DC power transmission cable transmits AC and DC simultaneously; the alternating current and direct current transmission cable filters alternating current through the first direct current filtering device and transmits direct current to the direct current load; the direct current is filtered through the first alternating current filtering device, and the alternating current is transmitted to an alternating current load. According to the application, the alternating current and the direct current can be simultaneously transmitted by using one power transmission cable, and the alternating current and the direct current are respectively transmitted to the alternating current load and the direct current load.

Description

Technical Field

[0001] The present application relates to the technical field of power generation, transmission and distribution of power systems, and in particular to an AC / DC interconnected micro power system based on the same transmission cable. Background Art

[0002] With the rapid development of new energy sources such as photovoltaic power generation and wind power generation, these power sources have generated a large amount of DC power or can be converted into DC power after simple conversion. The existing technology requires that these DC powers be incorporated into the AC distribution network after being inverted; on the other hand, new loads such as data centers and electric vehicles have rapidly emerged. These loads are DC loads. In the AC distribution network, the AC power needs to be rectified into DC power before it can be used; there are also energy storage power stations. The existing technology is to rectify the AC power of the AC grid into DC power for charging, and then invert the DC power and incorporate it into the AC distribution network when it is used; and with the development of power electronics technology, frequency conversion technology has been widely used in products such as air conditioners, washing machines, and refrigerators. The existing technology is to rectify the AC power into DC power and then invert the DC power into AC power with adjustable frequency and adjustable amplitude.

[0003] Therefore, the existing power system cannot directly deliver DC power to users for use, nor can it use the same transmission cable to simultaneously deliver AC and DC power to users for use. Summary of the invention

[0004] The purpose of this application is to provide an AC / DC interconnected micro power system based on the same transmission cable, which can use one transmission cable to simultaneously transmit AC and DC power, and deliver the AC and DC power to AC loads and DC loads respectively.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] The present application provides an AC / DC interconnected micro power system based on the same transmission cable, comprising: an AC / DC transmission cable, at least one DC power generation component, at least one AC power generation component, at least one first DC filter device, at least one first AC filter device, at least one DC load and at least one AC load.

[0007] One of the DC power generation components includes a DC power generation device, an inverter device and a DC regulation device; one of the AC power generation components includes an AC power generation device, a rectifier device and an AC regulation device.

[0008] The DC power generation device converts the generated DC power into AC power through an inverter device and then connects it to an AC / DC transmission cable; or the DC power generation device regulates the generated DC power through a DC regulation device and then connects it to an AC / DC transmission cable.

[0009] The AC power generation device converts the generated AC power into DC power through a rectifier and then connects it to an AC / DC transmission cable; or the AC power generation device regulates the generated AC power through an AC regulator and then connects it to an AC / DC transmission cable.

[0010] The AC / DC transmission cable is used to transmit AC and DC power simultaneously; the AC power transmitted by the AC / DC transmission cable has the same frequency and phase as the power grid and has a voltage amplitude; the DC power transmitted by the AC / DC transmission cable has a direction and a voltage value.

[0011] The AC / DC transmission cable is also used to filter out AC power through a first DC filter device and transmit the filtered DC power to a DC load; the AC / DC transmission cable is also used to filter out DC power through a first AC filter device and transmit the filtered AC power to an AC load.

[0012] According to the specific embodiments provided in this application, this application has the following technical effects:

[0013] The present application provides an AC / DC interconnected micro power system based on the same transmission cable, wherein the DC power and AC power generated by the DC power generation component and the AC power generation component can both be connected to the AC / DC transmission cable, and the AC / DC transmission cable simultaneously transmits the connected AC power and DC power, and the DC load filters out the AC power through a first DC filter device and can obtain DC power from the AC / DC transmission cable, and the AC load filters out the DC power through the first AC filter device and can obtain AC power from the AC / DC transmission cable, thereby achieving the goal of delivering AC power and DC power to the AC load and the DC load respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 A schematic diagram of the structure of an AC / DC interconnected micro power system based on the same transmission cable provided in one embodiment of the present application;

[0016] Figure 2 A schematic structural diagram of a two-core cable provided in another embodiment of the present application;

[0017] Figure 3 A schematic diagram of the structure of a four-core cable provided in another embodiment of the present application;

[0018] Figure 4A schematic diagram of the connection between a filter device and a two-core cable provided in another embodiment of the present application;

[0019] Figure 5 A schematic diagram of the connection between a filtering device and a four-core cable provided in another embodiment of the present application. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0021] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0022] In an exemplary embodiment, Figure 1 As shown, an AC / DC interconnected micro power system based on the same transmission cable is provided, comprising: an AC / DC transmission cable, at least one DC power generation component, at least one AC power generation component, at least one first DC filter device, at least one first AC filter device, at least one DC load and at least one AC load.

[0023] One of the DC power generation components includes a DC power generation device, an inverter device and a DC regulator device; one of the AC power generation components includes an AC power generation device, a rectifier device and an AC regulator device; the DC power generation device converts the generated DC power into AC power through the inverter device and then connects it to the AC / DC transmission cable; or the DC power generation device adjusts the generated DC power through the DC regulator device and then connects it to the AC / DC transmission cable; the AC power generation device converts the generated AC power into DC power through the rectifier device and then connects it to the AC / DC transmission cable; or the AC power generation device converts the generated AC power into DC power through the rectifier device and then connects it to the AC / DC transmission cable After adjustment by the AC adjustment device, the AC / DC transmission cable is connected; the AC / DC transmission cable is used to transmit AC and DC simultaneously; the AC transmitted by the AC / DC transmission cable has the same frequency and phase as the power grid and has a voltage amplitude; the DC transmitted by the AC / DC transmission cable has a direction and a voltage value; the AC / DC transmission cable is also used to filter out the AC through a first DC filter device and transmit the filtered DC to a DC load; the AC / DC transmission cable is also used to filter out the DC through a first AC filter device and transmit the filtered AC to an AC load.

[0024] Exemplarily, the AC / DC transmission cable can carry both AC and DC power at the same time, and the voltage level is preferably low voltage.

[0025] Exemplarily, the DC regulating device may be a DC voltage regulating device for regulating DC voltage. The AC regulating device may be an AC voltage frequency regulating device for regulating AC voltage and frequency. The AC regulating device and the DC regulating device may also be other devices capable of regulating AC and DC.

[0026] In another exemplary embodiment of the present application, the DC power generation device is a photovoltaic power generation system, a DC wind power generation system or an energy storage power station. The AC power generation device is an AC wind power generation system that generates industrial frequency or an AC wind power generation system that generates medium and low frequencies; the frequency of the medium and low frequencies is less than the frequency threshold. When the DC power generation device is an energy storage power station, and the energy storage power station is charged: the AC power in the AC and DC transmission cables is converted into DC power by a rectifier and then charged into the energy storage power station; or the DC power in the AC and DC transmission cables is charged into the energy storage battery through a DC regulating device.

[0027] Reference Figure 1 , the DC power of the distributed photovoltaic power generation system can be converted into AC power through an inverter device, and then connected to the transmission cable (AC / DC transmission cable) after filtering by a filter device; or the DC power can be connected to the transmission cable after being adjusted by a DC regulator after passing through a filter device. The DC power of the distributed DC wind power generation system can be converted into AC power through an inverter device, and then connected to the transmission cable after filtering by a filter device; or the DC power can be connected to the transmission cable after being adjusted by an AC regulator after passing through a filter device. The AC power of the distributed AC (industrial frequency) wind power generation system can be connected to the transmission cable after filtering by a filter device. The AC power of the distributed AC (medium frequency, low frequency) wind power generation system can be converted into DC power through a rectifier device, and then connected to the transmission cable after filtering by a filter device. When the distributed energy storage power station is discharged, the DC power can be converted into AC power through an inverter device, and then connected to the transmission cable after filtering by a filter device; or the DC power can be connected to the transmission cable after being adjusted by a DC regulator after passing through a filter device. When the distributed energy storage power station is charging, the AC power in the transmission cable can be filtered by the filter device and then converted into DC power through the rectifier device and charged into the energy storage battery; or the DC power can be adjusted by the DC regulator through the filter device and then charged into the energy storage battery.

[0028] Figure 1 PV in the word refers to photovoltaic power generation, which is spelled as Photovoltaic in English. The full name of PCS in English is Power Conversion System, which means "power conversion system" in Chinese. PMU refers to power management unit, which is spelled as Pressure Measuring Unit in English.

[0029] In another exemplary embodiment of the present application, when the DC power generation device is a photovoltaic power generation system or a DC wind power generation system, the inverter device is an INV inverter; when the DC power generation device is an energy storage power station, the inverter device is a PCS inverter; the DC regulation device is a DC / DC converter; the rectifier device is an AC / DC converter; and the AC regulation device is an AC / AC converter. Figure 1 INV in the figure refers to an INV inverter, and CON refers to a DC / DC converter or an AC / AC converter.

[0030] In another exemplary embodiment of the present application, a DC power generation component further includes: a first power management unit, a second AC filter device, and a second DC filter device. The first power management unit is connected to the inverter device and the DC regulator device respectively; the first power management unit is used to control the working state of the inverter device and the working state of the DC regulator device; the second AC filter device is connected to the inverter device and the AC / DC transmission cable respectively; the second AC filter device is used to filter out the DC power under the control of the first power management unit, connect the AC power converted by the inverter device to the AC / DC transmission cable, and prevent the DC power on the AC / DC transmission cable from invading the inverter device; the second DC filter device is connected to the DC regulator device and the AC / DC transmission cable respectively; the second DC filter device is used to filter out the AC power, connect the DC power regulated by the DC regulator device to the AC / DC transmission cable, and prevent the AC power on the AC / DC transmission cable from invading the DC regulator.

[0031] AC filter device( Figure 1 C2 and C3 in the figure have the function of filtering the DC component in the system in the forward or reverse direction. Figure 1 RL2 and RL3 in the figure have the function of filtering the AC components in the system in the forward or reverse direction.

[0032] In another exemplary embodiment of the present application, an AC power generation component further includes: a second power management unit, a third AC filter device, and a third DC filter device. The second power management unit is connected to the rectifier device and the AC regulator device respectively; the second power management unit is used to control the working state of the rectifier device and the working state of the AC regulator device; the third DC filter device is connected to the rectifier device and the AC / DC transmission cable respectively; the third DC filter device is used to filter out the AC power, connect the DC power converted by the rectifier device to the AC / DC transmission cable, and prevent the AC power on the AC / DC transmission cable from invading the rectifier device; the third AC filter device is connected to the AC regulator device and the AC / DC transmission cable respectively; the third AC filter device is used to filter out the DC power, connect the AC power regulated by the AC regulator device to the AC / DC transmission cable, and prevent the DC power on the AC / DC transmission cable from invading the AC regulator device.

[0033] In another exemplary embodiment of the present application, the AC / DC interconnected micro power system based on the same transmission cable further includes: a central power management module. The central power management module is connected to the first power management unit and the second power management unit respectively. The central power management module is used to centrally and uniformly manage and dispatch the first power management unit and the second power management unit.

[0034] The central power management module and the power management unit realize the controlled output of DC and AC power of the distributed photovoltaic power generation system by controlling the inverter device. The central power management module and the PMU realize the controlled output of DC and AC power of the distributed DC wind power generation system by controlling the inverter device. The central power management module and the PMU realize the controlled output of DC and AC power of the distributed three-phase AC (industrial frequency) wind power generation system by controlling the converter device. The central power management module and the PMU realize the controlled output of DC and AC power of the distributed three-phase AC (medium frequency, low frequency) wind power generation system by controlling the converter device. The central power management module and the PMU realize the controlled output or input of DC and AC power of the distributed energy storage power station by controlling the converter device.

[0035] In an exemplary embodiment, the central power management module coordinates and controls the dispersed power generation and supply objects through the system's power flow constraints, frequency constraints, overload constraints, etc., so that the AC and DC loads are automatically balanced.

[0036] In another exemplary embodiment of the present application, when the inverter device converts DC power into single-phase AC power, the AC / DC transmission cable is a two-core cable, such as Figure 2 When the inverter converts DC power into three-phase AC power, the AC / DC transmission cable is a four-core cable, as shown in Figure 3 shown. Figure 3 The -0 in refers to the zero line.

[0037] In an exemplary embodiment, when the AC / DC power transmission cable adopts a two-core cable, the second AC filter device is a single-phase AC filter device, and the second DC filter device is a single-phase DC filter device; one end of the single-phase AC filter device is connected to the L1 terminal and the N' terminal of the inverter device, and the other end of the single-phase AC filter device is connected to the +L line and -N line of the two-core cable; one end of the single-phase DC filter device is connected to the L+ terminal and the L- terminal of the DC regulating device, and the other end of the single-phase DC filter device is connected to the +L line and -N line of the two-core cable.

[0038] like Figure 4 As shown, when the AC and DC power transmission cables use a two-core cable, the second AC filtering device includes a first capacitor and a second capacitor, and the second DC filtering device includes a first RL filter and a second RL filter.

[0039] One end of the first capacitor is connected to the L1 terminal of the inverter device, and the other end of the first capacitor is connected to the +L line of the two-core cable; one end of the second capacitor is connected to the N' terminal of the inverter device, and the other end of the second capacitor is connected to the -N line of the two-core cable. One end of the first RL filter is connected to the L+ terminal of the DC power generation device, and the other end of the first RL filter is connected to the +L line of the two-core cable; one end of the second RL filter is connected to the L- terminal of the DC power generation device, and the other end of the second RL filter is connected to the -N line of the two-core cable.

[0040] Reference Figure 4 The DC power of the distributed photovoltaic power generation system is converted into single-phase AC power through an inverter device, and connected to the filter device through terminals L1 and N' and then connected to the transmission cable after filtering; or the DC power is connected to the filter device through terminals L+ and L- and then connected to the transmission cable after filtering.

[0041] The DC power of the distributed DC wind power generation system is converted into single-phase AC power through an inverter device, and connected to a filter device through terminals L1 and N' for filtering and then connected to a transmission cable; or the DC power is connected to a filter device through terminals L+ and L- for filtering and then connected to a transmission cable.

[0042] The AC power of the distributed single-phase AC (industrial frequency) wind power generation system is connected to the filter device through terminals L1 and N' and then connected to the transmission cable after filtering; or the single-phase AC (industrial frequency) power is converted into DC power through a rectifier device and connected to the filter device through terminals L+ and L- and then connected to the transmission cable after filtering.

[0043] The AC power of the distributed single-phase AC (medium frequency, low frequency) wind power generation system is converted into industrial frequency single-phase AC power through a converter, connected to a filter device via terminals L1 and N' and then connected to the transmission cable after filtering; or the single-phase AC (medium frequency, low frequency) power is converted into DC power through a rectifier device, connected to a filter device via terminals L+ and L- and then connected to the transmission cable after filtering.

[0044] When the distributed energy storage power station discharges, the DC power is converted into single-phase AC power through the inverter device, and connected to the filter device through terminals L1 and N' for filtering and then connected to the transmission cable; or the DC power is connected to the filter device through terminals L+ and L- for filtering and then connected to the transmission cable.

[0045] When the distributed energy storage power station is charging, the single-phase AC power in the transmission cable is filtered by the filter device, converted into DC power through the terminals L+ and L- through the rectification device, and charged into the energy storage battery; or the DC power is charged into the energy storage battery through the filter device through the terminals L+ and L- through the DC / DC converter.

[0046] The DC load is connected to the terminals L+ and L-, and uses the DC power filtered by the filter device in the transmission cable. The single-phase AC load is connected to the terminals L1 and N', and uses the single-phase AC power filtered by the filter device in the transmission cable.

[0047] In another exemplary embodiment, when the AC / DC power transmission cable adopts a four-core cable, the third AC filter device is a three-phase AC filter device, and the third DC filter device is a three-phase DC filter device; one end of the three-phase AC filter device is connected to the L1 terminal, L2 terminal, L3 terminal and N' terminal of the inverter device, and the other end of the three-phase AC filter device is connected to the +c line, -b line, +a line and -0 line of the four-core cable; one end of the three-phase DC filter device is connected to the L+ terminal, L- terminal, L+ terminal and L- terminal of the DC regulation device, and the other end of the three-phase DC filter device is connected to the +c line, -b line, +a line and -0 line of the four-core cable.

[0048] like Figure 5 As shown, when the AC and DC transmission cables use four-core cables, the third AC filtering device includes a third capacitor, a fourth capacitor, a fifth capacitor and a sixth capacitor, and the third DC filtering device includes a third RL filter, a fourth RL filter, a fifth RL filter and a sixth RL filter.

[0049] One end of the third capacitor is connected to the L1 terminal of the AC generator, and the other end of the third capacitor is connected to the +c phase line of the four-core cable; one end of the fourth capacitor is connected to the L2 terminal of the AC generator, and the other end of the fourth capacitor is connected to the -b phase line of the four-core cable; one end of the fifth capacitor is connected to the L3 terminal of the AC generator, and the other end of the fifth capacitor is connected to the +a phase line of the four-core cable; one end of the sixth capacitor is connected to the N' terminal of the AC generator, and the other end of the sixth capacitor is connected to the neutral line of the four-core cable.

[0050] One end of the third RL filter is connected to the L+ terminal of the rectifier, and the other end of the third capacitor is connected to the +c phase line of the four-core cable; one end of the fourth capacitor is connected to the L- terminal of the rectifier, and the other end of the fourth capacitor is connected to the -b phase line of the four-core cable; one end of the fifth capacitor is connected to the L+ terminal of the rectifier, and the other end of the fifth capacitor is connected to the +a phase line of the four-core cable; one end of the sixth capacitor is connected to the L- terminal of the rectifier, and the other end of the sixth capacitor is connected to the neutral line of the four-core cable.

[0051] The DC power of the distributed photovoltaic power generation system is converted into three-phase AC power through an inverter device, and connected to the filter device through terminals L1, L2, L3, and N' for filtering and then connected to the transmission cable; or the DC power is connected to the filter device through terminals L+ and L- for filtering and then connected to the transmission cable.

[0052] The DC power of the distributed DC wind power generation system is converted into three-phase AC power through an inverter device, and connected to the filter device through terminals L1, L2, L3, and N' for filtering and then connected to the transmission cable; or the DC power is connected to the filter device through terminals L+ and L- for filtering and then connected to the transmission cable.

[0053] The AC power of the distributed three-phase AC (industrial frequency) wind power generation system is connected to the filter device through terminals L1, L2, L3, and N' and then connected to the transmission cable after filtering; or the AC (industrial frequency) power is converted into DC power through a rectifier device and connected to the filter device through terminals L+ and L- and then connected to the transmission cable after filtering.

[0054] The AC power of the distributed three-phase AC (medium frequency, low frequency) wind power generation system is converted into industrial frequency three-phase AC power through a converter, connected to a filter device via terminals L1, L2, L3, and N', and then connected to the transmission cable after filtering; or the AC (medium frequency, low frequency) power is converted into DC power through a rectifier device, connected to a filter device via terminals L+ and L-, and then connected to the transmission cable after filtering.

[0055] When the distributed energy storage power station discharges, the DC power is converted into three-phase AC power through the inverter device, and connected to the filter device through terminals L1, L2, L3, and N', and then connected to the transmission cable after filtering; or the DC power is connected to the filter device through terminals L+ and L-, and then connected to the transmission cable after filtering.

[0056] When the distributed energy storage power station is charging, the three-phase AC power in the transmission cable is filtered by the filter device and then converted into DC power through the rectifier device, and then charged into the energy storage battery through the terminals L+ and L-; or the DC power is charged into the energy storage battery through the filter device, through the terminals L+ and L-, and through the DC / DC converter.

[0057] The DC load connection terminals L+ and L- use the DC power filtered by the filter device in the transmission cable. The three-phase AC load connection terminals L1, L2, L3, and N' use the three-phase AC power filtered by the filter device in the transmission cable.

[0058] The DC load uses the DC power filtered by the filter device RL1 in the transmission cable. The AC load uses the AC power filtered by the filter device C1 in the transmission cable.

[0059] In another exemplary embodiment of the present application, please refer to Figure 1 The AC / DC interconnected micro power system based on the same transmission cable also includes: an isolation transformer and a fourth AC filter device. The isolation transformer is connected to the fourth AC filter device and the power grid respectively; the fourth AC filter device is connected to the AC / DC transmission cable. The AC power of the power grid is transmitted to the AC / DC transmission cable after passing through the isolation transformer and the fourth AC filter device. The AC power of the AC / DC transmission cable is transmitted to the power grid after passing through the fourth AC filter device and the isolation transformer.

[0060] That is, the isolation transformer connects the micro power system to the AC power grid, and inputs electric energy from the grid to the micro power system, or outputs electric energy from the micro power system to the grid.

[0061] The present application discloses an AC / DC interconnected micro power system based on the same transmission cable, which has the following characteristics:

[0062] Wind power generation, photovoltaic power generation and energy storage stations are the main suppliers of electric energy. All kinds of energy are interconnected and can be converted to each other. AC and DC share the same transmission cable. Most of the electric energy is consumed within the system. The source, grid, load and storage interact with each other, and the decentralized power generation, supply and use objects are coordinated and controlled. Under the condition of a certain total power load, the AC and DC loads are automatically balanced. The micro power system is connected to the large industrial frequency power grid.

[0063] The transmission mechanisms of alternating current and direct current in cables are different: alternating current moves back and forth through the electrons in the conductor, and the direction and size of these electrons are constantly changing, which causes changes in the electromagnetic field. The alternating magnetic field formed in the cable will generate an alternating electric field around the conductor. This alternating electromagnetic field will constantly change with the change of current, thereby generating induced electromotive force and eddy current, resulting in energy loss. In contrast, the electrons in direct current only move in one direction and do not change direction and size like alternating current. Therefore, the electromagnetic field formed in the cable is static, and no induced electromotive force and eddy current will be generated, thereby reducing energy loss.

[0064] In order to be able to transmit AC and DC simultaneously in the same cable, the AC and DC transmission cables of the present application have a higher voltage resistance level, special insulation materials, and a structural design that can withstand different current properties to ensure the safe transmission of the two currents.

[0065] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0066] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. An AC / DC interconnected micro power system based on the same transmission cable, characterized in that: The AC / DC interconnected micro power system based on the same transmission cable comprises: an AC / DC transmission cable, at least one DC power generation component, at least one AC power generation component, at least one first DC filter device, at least one first AC filter device, at least one DC load and at least one AC load; One of the DC power generation components includes a DC power generation device, an inverter device and a DC regulator device; one of the AC power generation components includes an AC power generation device, a rectifier device and an AC regulator device; The DC power generation device converts the generated DC power into AC power through an inverter device and then connects it to an AC / DC transmission cable; or the DC power generation device regulates the generated DC power through a DC regulation device and then connects it to an AC / DC transmission cable; The AC power generation device converts the generated AC power into DC power through a rectifying device and then connects the generated AC power to an AC / DC transmission cable; or the AC power generation device regulates the generated AC power through an AC regulating device and then connects the generated AC power to an AC / DC transmission cable; The AC / DC transmission cable is used to transmit AC and DC power simultaneously; the AC power transmitted by the AC / DC transmission cable has the same frequency and phase as the power grid and has a voltage amplitude; the DC power transmitted by the AC / DC transmission cable has a direction and a voltage value; The AC / DC power transmission cable is also used to filter the AC power through a first DC filter device and transmit the filtered DC power to a DC load; The AC / DC power transmission cable is also used to filter out DC power through a first AC filter device and transmit the filtered AC power to an AC load.

2. The AC / DC interconnected micro power system based on the same transmission cable according to claim 1, characterized in that: The DC power generation device is a photovoltaic power generation system, a DC wind power generation system or an energy storage power station; The AC power generation device is an AC wind power generation system that generates industrial frequency or an AC wind power generation system that generates medium or low frequency; the frequency of the medium or low frequency is less than the frequency threshold; When the DC power generation device is an energy storage power station, and the energy storage power station is charging: The AC power in the AC / DC transmission cables is converted into DC power by a rectifier and then charged into the energy storage power station; Alternatively, the DC power in the AC / DC transmission cables is charged into the energy storage battery through a DC regulating device.

3. The AC / DC interconnected micro power system based on the same transmission cable according to claim 2, characterized in that: When the DC power generation device is a photovoltaic power generation system or a DC wind power generation system, the inverter device is an INV inverter; when the DC power generation device is an energy storage power station, the inverter device is a PCS inverter; The DC regulating device is a DC / DC converter; The rectifier is an AC / DC converter; The AC regulating device is an AC / AC converter.

4. The AC / DC interconnected micro power system based on the same transmission cable according to claim 3, characterized in that: One of the DC power generation components also includes: a first power management unit, a second AC filter device, and a second DC filter device; The first power management unit is connected to the inverter device and the DC regulator device respectively; the first power management unit is used to control the working state of the inverter device and the working state of the DC regulator device; The second AC filter device is connected to the inverter device and the AC / DC transmission cable respectively; the second AC filter device is used to filter out DC power under the control of the first power management unit, connect the AC power converted by the inverter device to the AC / DC transmission cable, and prevent the DC power on the AC / DC transmission cable from invading the inverter device; The second DC filtering device is connected to the DC regulating device and the AC / DC transmission cable respectively; the second DC filtering device is used to filter out AC power, connect the DC power regulated by the DC regulating device to the AC / DC transmission cable, and prevent the AC power on the AC / DC transmission cable from invading the DC regulating device.

5. The AC / DC interconnected micro power system based on the same transmission cable according to claim 4, characterized in that: One of the AC power generation components also includes: a second power management unit, a third AC filter device and a third DC filter device; The second power management unit is connected to the rectifier device and the AC regulator device respectively; the second power management unit is used to control the working state of the rectifier device and the working state of the AC regulator device; The third DC filter device is connected to the rectifier device and the AC / DC transmission cable respectively; the third DC filter device is used to filter out the AC power, connect the DC power converted by the rectifier device to the AC / DC transmission cable, and prevent the AC power on the AC / DC transmission cable from invading the rectifier device; The third AC filtering device is connected to the AC regulating device and the AC and DC transmission cables respectively; the third AC filtering device is used to filter out DC power, connect the AC power regulated by the AC regulating device to the AC and DC transmission cables, and prevent the DC power on the AC and DC transmission cables from invading the AC regulating device.

6. The AC / DC interconnected micro power system based on the same transmission cable according to claim 5, characterized in that: The AC / DC interconnected micro power system based on the same transmission cable also includes: a central power management module; The central power management module is connected to the first power management unit and the second power management unit respectively; the central power management module is used to centrally and uniformly manage and schedule the first power management unit and the second power management unit.

7. The AC / DC interconnected micro power system based on the same transmission cable according to claim 1 or 3, characterized in that: When the inverter device converts direct current into single-phase alternating current, the AC / DC transmission cable is a two-core cable; When the inverter device converts direct current into three-phase alternating current, the AC / DC transmission cable is a four-core cable.

8. The AC / DC interconnected micro power system based on the same transmission cable according to claim 7, characterized in that: When the AC / DC power transmission cable adopts a two-core cable, the second AC filter device is a single-phase AC filter device, and the second DC filter device is a single-phase DC filter device; One end of the single-phase AC filter device is connected to the L1 terminal and the N' terminal of the inverter device, and the other end of the single-phase AC filter device is connected to the +L line and the -N line of the two-core cable; One end of the single-phase DC filter device is connected to the L+ terminal and the L- terminal of the DC regulator, and the other end of the single-phase DC filter device is connected to the +L line and the -N line of the two-core cable.

9. The AC / DC interconnected micro power system based on the same transmission cable according to claim 7, characterized in that: When the AC / DC power transmission cable adopts a four-core cable, the third AC filter device is a three-phase AC filter device, and the third DC filter device is a three-phase DC filter device; One end of the three-phase AC filter device is connected to the L1 terminal, L2 terminal, L3 terminal and N' terminal of the inverter device, and the other end of the three-phase AC filter device is connected to the +c line, -b line, +a line and -0 line of the four-core cable; One end of the three-phase DC filter device is connected to the L+ terminal, L- terminal, L+ terminal and L- terminal of the DC regulator, and the other end of the three-phase DC filter device is connected to the +c line, -b line, +a line and -0 line of the four-core cable.

10. The AC / DC interconnected micro power system based on the same transmission cable according to claim 1, characterized in that: The AC / DC interconnected micro power system based on the same transmission cable also includes: an isolation transformer and a fourth AC filter device; The isolation transformer is connected to the fourth AC filter device and the power grid respectively; the fourth AC filter device is connected to the AC and DC power transmission cables; The AC power of the power grid is transmitted to the AC and DC power transmission cables after passing through the isolation transformer and the fourth AC filter device; The AC power of the AC / DC transmission cable is transmitted to the power grid after passing through the fourth AC filter device and the isolation transformer. Meanwhile, the fourth AC filter device prevents the DC power on the AC / DC transmission cable from invading the isolation transformer.

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