Digital direct current transmission system and method based on communication channel cooperative scheduling

Abstract

The invention discloses a digital direct current transmission system and method based on communication channel collaborative scheduling, and relates to the cross technical field of communication and novel power systems, and the system comprises a direct current source, an energy base station, an intelligent load, a power transmission line and a communication channel. The direct current source is used for providing direct current power; the energy base station is used for receiving the direct current power and generating and scheduling an energy packet; the intelligent load is used for receiving and processing the transmitted energy packet, performing communication interaction with the energy base station, and proposing an energy supply request or feeding back a load state; the power transmission line is used for transmitting energy packets between the energy base stations; and the communication channel is used for coordinating scheduling and transmission of the energy packets among the energy base stations, and a wired or wireless communication mode can be adopted. According to the invention, the energy packet is transmitted in a digital discrete mode, and the source side can obtain the request information of the load through the communication channel and send the corresponding energy packet, so that accurate and timed scheduling of electric energy is realized, and the power flow is flexibly managed.

Description

Technical Field

[0001] The present invention belongs to the cross-technical field of communication and novel power systems, and in particular relates to a digital direct current transmission system and method based on coordinated dispatching of communication channels. Background Art

[0002] At present, DC power transmission technology has been widely used in the fields of high-voltage DC transmission, microgrids, and renewable energy generation. However, the traditional DC transmission method still faces problems such as unstable energy transmission, difficult power scheduling, and large power loss. In recent years, discrete power transmission based on energy packets has become a research hotspot. It divides electricity into independent energy packets for transmission, thereby improving transmission efficiency and enhancing scheduling flexibility. The existing technology attaches transmission information to the effective energy in the form of fixed byte pulses, which reduces the effective energy ratio of the transmitted energy packet, and the reliability of the system is also affected by information recognition. High-frequency square wave signals are also not suitable for long-distance transmission and have great limitations. In addition, the existing transmission system cannot meet the information interaction between the load and the source side, which makes it impossible for the source side to autonomously perform corresponding energy transmission according to the needs of the load side. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a digital DC transmission system and method based on collaborative scheduling of communication channels, which transmits information through communication channels so that the energy packet accounts for 100%. The source side can send the corresponding energy packet according to the load request information to achieve accurate and timely scheduling of electric energy.

[0004] On the one hand, to achieve the above-mentioned purpose, the present invention provides a digital DC transmission system based on communication channel coordinated scheduling, comprising: DC sources, energy base stations, smart loads, power transmission lines and communication channels; The DC source is used to provide DC power; The energy base station is used to receive DC power and generate and dispatch energy packets; The smart load is used to receive and process the transmitted energy packets, communicate and interact with the energy base station, make energy supply requests or feedback load status; The power transmission line is used to transmit energy packets between the energy base stations; The communication channel is used to coordinate the scheduling and transmission of energy packets between the energy base stations.

[0005] Optionally, the energy base station includes an energy distributor and an energy packet scheduling controller; The energy distributor is used to select a transmission path of the energy packet according to the control signal and transmit the energy packet to a designated location; The energy packet scheduling controller is used to issue control instructions for generating or scheduling energy packets according to power demand and transmission status.

[0006] Optionally, the energy distributor is composed of a multi-port power electronic converter based on fully-controlled power electronic devices, and the fully-controlled power electronic devices include but are not limited to devices made of silicon carbide and gallium nitride wide bandgap materials.

[0007] Optionally, the energy packet scheduling controller includes a sampler, a first communication module and a controller; The sampler is used to collect the transmission status of the power grid in real time and assist in the accurate dispatch of energy packets; The first communication module is used for information communication between the energy base station and the smart load, the energy base station and the DC source, and the energy base stations and the energy base stations; The controller is used to issue control instructions for generating or scheduling energy packets according to the information returned by the sampler and the first communication module.

[0008] Optionally, the intelligent load includes a buffer, a second communication module and a load device; The buffer is used for smooth reception of energy packets; The second communication module is used for interaction between the smart load and the energy base station and real-time feedback of load demand information; The load device is used to receive the energy packet.

[0009] Optionally, the buffer may be, but is not limited to, a supercapacitor, a battery or other energy storage devices.

[0010] Optionally, the communication channel includes but is not limited to communicating by wired transmission or wireless transmission.

[0011] On the other hand, to achieve the above-mentioned purpose, the present invention also provides a digital DC transmission method based on communication channel coordinated scheduling, comprising: S1. The smart load accesses the energy base station and uploads the corresponding load information, thereby generating a smart load request information queue and determining the transmission order of the energy packet; S2, the smart load makes an energy request; S3, the energy base station on the smart load side identifies the energy request information of the first queue, and if there is an energy request, transmits the energy request to the energy base station on the DC source side through the communication channel, and sets the request flag bit of the port corresponding to the smart load in the energy packet scheduling controller on the smart load side, which is used to subsequently determine whether the transmission channel is open. If there is no energy request, execute S8; S4, the DC source side energy base station receives the information and generates the capability package required by the smart load, and transmits it through the power transmission line; S5, the sampler in the energy base station on the smart load side monitors the power grid state. If there is no energy packet transmission or there is energy packet transmission for non-corresponding smart loads, then continue to execute S5. If there is energy packet transmission required by the corresponding smart load, then execute S6; S6, check whether the request flag bit of the port corresponding to the intelligent load is set, if not set, execute S5, if set, execute S7; S7, the energy base station on the smart load side opens the transmission channel to transmit the energy packet to the smart load at the corresponding port, and the smart load receives the energy packet after being smoothed by the buffer; S8. The sampler in the energy base station on the smart load side monitors the power grid status. If there is energy packet transmission required by the corresponding load, continue to execute S7. If there is no energy packet transmission, close the transmission channel, reset the request flag of the corresponding port of the smart load, and determine whether the request information is submitted by the last smart load in the queue. If not, execute S3 to respond to the energy request of the next load. If so, execute S2.

[0012] Optionally, the load information includes the address, voltage level and power level of the smart load.

[0013] Optionally, the energy request includes the address of the smart load, the address of the requested DC source, and the time and size of the required energy.

[0014] Technical effect of the invention: The present invention discloses a digital DC transmission system and method based on coordinated scheduling of communication channels, which improves the effective energy ratio of energy packets, adopts independent communication channels to transmit control information, avoids additional information occupying the energy packet space, and improves the energy transmission efficiency; improves the stability of energy transmission, adopts digital discrete energy packet transmission and coordinated scheduling of communication channels, reduces voltage fluctuations, and ensures stable power supply; improves the flexibility of power scheduling, introduces an energy packet scheduling controller, realizes the interaction between the load side and the source side, and improves the accuracy and response speed of energy distribution; reduces power loss, improves long-distance transmission efficiency, optimizes the energy packet modulation method, reduces high-frequency signal loss, and improves long-distance power transmission capacity; solves the information interaction problem between the source side and the load side, adopts a two-way communication mechanism, so that the source side can dynamically adjust the energy packet output according to the load demand, and realizes adaptive power supply; improves the reliability and adaptability of the system, transmits control information through independent communication channels, improves the stability of information transmission, and is suitable for various application scenarios such as microgrids and new energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings: Figure 1 This is a schematic diagram of an energy package according to an embodiment of the present invention; Figure 2 It is a structural schematic diagram of a digital DC transmission system based on communication channel coordinated scheduling according to an embodiment of the present invention; Figure 3 This is a structural diagram of an energy distributor according to an embodiment of the present invention; Figure 4 This is an overall structural diagram of an energy base station according to an embodiment of the present invention; Figure 5 This is a schematic diagram of a smart load according to an embodiment of the present invention; Figure 6 It is a flow chart of a digital direct current transmission method based on communication channel coordinated scheduling according to an embodiment of the present invention; Figure 7 A schematic diagram of a simulation of a digital DC transmission system based on collaborative scheduling of communication channels according to an embodiment of the present invention; Figure 8 A schematic diagram of simulation results of energy packets received by each smart load according to an embodiment of the present invention; Fig. 9 This is a physical picture of an energy base station according to an embodiment of the present invention; Fig.10 Schematic diagram of experimental results of energy packets received by each smart load in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0017] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0018] Figure 1 A schematic diagram of the energy packet described in this embodiment is given. The energy packet only carries effective power and does not contain any communication information. The energy size and voltage size carried by each energy packet are generated according to the load energy request information.

[0019] like Figure 2 As shown, in this embodiment, a digital DC transmission system based on communication channel coordinated scheduling is provided, including: a DC source, an energy base station, a smart load, a power transmission line and a communication channel; The DC source is used to provide DC power; The energy base station is used to receive DC power and generate and dispatch energy packets; The smart load is used to receive and process the transmitted energy packets, communicate and interact with the energy base station, make energy supply requests or feedback load status; The power transmission line is used to transmit energy packets between the energy base stations; The communication channel is used to coordinate the scheduling and transmission of energy packets between the energy base stations.

[0020] Furthermore, the DC source includes a renewable energy DC power supply, an energy storage system DC power supply, a DC microgrid power supply system, and a traditional DC power supply.

[0021] Further, such as Figure 4 As shown, the energy base station includes an energy distributor and an energy packet scheduling controller; The energy distributor is used to select the transmission path of the energy packet according to the control signal and transmit the energy packet to the specified location; the fully controlled power electronic devices include but are not limited to devices made of wide bandgap semiconductor materials such as silicon carbide (SiC) and gallium nitride (GaN), such as SiC MOSFET and GaN HEMT.

[0022] The energy packet scheduling controller is used to issue control instructions for generating or scheduling energy packets according to power demand and transmission status.

[0023] Specifically, in this embodiment, the energy base station is composed of an energy distributor and an energy packet scheduling controller, wherein the energy distributor is composed of a multi-port power electronic converter based on a wide bandgap device, and the structure is as follows: Figure 3 As shown, port 3 is connected in parallel with a switch tube made of a wide bandgap device to connect the power transmission channel and serve as the energy packet receiving or sending port shared by port 1 and port 2. Port 1 and port 2 can be connected to different DC sources or smart loads, and a set of reverse series switch tubes made of wide bandgap devices are connected in series on their respective transmission channels to achieve bidirectional power flow. By controlling the driving signal of each switch tube, the transmission path of the energy packet can be selected and the energy packet can be accurately delivered to the specified location; the energy packet scheduling controller is used to issue control instructions for generating or scheduling energy packets according to power demand and transmission status.

[0024] Further, the energy packet scheduling controller includes a sampler, a first communication module and a controller; The sampler is used to collect the transmission status of the power grid in real time and return the real-time voltage value of the power grid to the controller to determine whether there is energy packet transmission and assist in the accurate scheduling of energy packets; The first communication module is used for information communication between the energy base station and the smart load, the energy base station and the DC source, and the energy base stations and the energy base stations; The controller is used to issue control instructions for generating or scheduling energy packets according to the information returned by the sampler and the first communication module, control the on and off of the switch tube in the energy distributor, and realize energy packet transmission.

[0025] Further, such as Figure 5 As shown, the intelligent load includes a buffer, a second communication module and a load device; The buffer is used for smooth reception of energy packets; The second communication module is used for interaction between the smart load and the energy base station and real-time feedback of load demand information; The load device is used to receive a capability packet.

[0026] Furthermore, the load device may be, but is not limited to, a DC air conditioner, a DC LED lighting system, a server rack, and a smart home appliance.

[0027] Furthermore, the buffer may be, but is not limited to, a supercapacitor, a battery or other energy storage devices.

[0028] Furthermore, power transmission lines are used to transport discrete energy packets in the form of overhead lines, cable transmission and busbar transmission, with low loss, high stability and electromagnetic compatibility, and are suitable for DC microgrids, high-voltage DC transmission and new energy systems.

[0029] Furthermore, the communication channel may be, but is not limited to, wired transmission (optical fiber) or wireless transmission for communication, wherein the wired communication method may be, but is not limited to, optical fiber communication, Ethernet communication, and CAN bus communication, and the wireless communication method may be, but is not limited to, Zigbee, Wi-Fi, and 5G / 4G LTE.

[0030] like Figure 6 As shown, this embodiment also provides a digital DC transmission method based on communication channel coordinated scheduling, including: S1. The smart load accesses the energy base station and uploads the corresponding load information, thereby generating a smart load request information queue and determining the transmission order of the energy packet; Specifically, in this embodiment, smart load 1 and smart load 2 are connected to the energy base station and upload corresponding load information to the energy packet scheduling controller. The load information includes the address, voltage level, power level, etc. of the load, and then a smart load request information queue is generated accordingly to determine the transmission order of the energy packet as A1, A2; S2, the smart load makes an energy request; Specifically, in this embodiment, the intelligent load proposes energy requests Q1, Q2, which include the address of the load, the address of the requested DC source, the time and size of the required energy, etc., as shown in the following Table 1; Table 1

[0031] S3, the energy base station on the smart load side identifies the energy request information of the first queue, and if there is an energy request, transmits the energy request to the energy base station on the DC source side through the communication channel, and sets the request flag bit of the port corresponding to the smart load in the energy packet scheduling controller on the smart load side, which is used to subsequently determine whether the transmission channel is open. If there is no energy request, execute S8; S4, the DC source side energy base station receives the information and generates the capability package required by the smart load, and transmits it through the power transmission line; S5, the sampler in the energy base station on the smart load side monitors the power grid state. If there is no energy packet transmission or there is energy packet transmission for non-corresponding smart loads, then continue to execute S5. If there is energy packet transmission required by the corresponding smart load, then execute S6; S6, check whether the request flag bit of the port corresponding to the intelligent load is set, if not set, execute S5, if set, execute S7; S7, the energy base station on the smart load side opens the transmission channel to transmit the energy packet to the smart load at the corresponding port, and the smart load receives the energy packet after being smoothed by the buffer; S8. The sampler in the energy base station on the smart load side monitors the power grid status. If there is energy packet transmission required by the corresponding load, continue to execute S7. If there is no energy packet transmission, close the transmission channel, reset the request flag of the corresponding port of the smart load, and determine whether the request information is submitted by the last smart load in the queue. If not, execute S3 to determine the energy request of the next load. If so, execute S2.

[0032] Furthermore, the load information in S1 includes the address, voltage level and power level of the smart load.

[0033] Furthermore, the energy request in S2 includes the address of the smart load, the address of the requested DC source, and the time and amount of the required energy.

[0034] Furthermore, the energy base station on the DC source side in S4 generates the capability package required by the smart load according to the smart load request information by controlling the transmission channel of the DC source requested by the smart load corresponding to the energy request information, and the transmission channels of the other DC sources remain closed.

[0035] Furthermore, in S5, if the grid voltage is the voltage of the DC source requested by the smart load corresponding to the energy request information, it is determined that there is energy packet transmission required by the corresponding smart load; if the grid voltage is 0 or the grid voltage is not the voltage of the DC source requested by the smart load corresponding to the energy request information, it is determined that there is no energy packet transmission or there is energy packet transmission for a non-corresponding smart load.

[0036] In this embodiment, the simulink simulation tool in MATLAB is used to build a digital DC transmission system simulation based on communication channel coordinated scheduling. Figure 7 The simulation results show that the energy packets received by each smart load are as follows: Figure 8 As shown, the energy pack voltage of smart load 1 is 25V, and the energy pack voltage of smart load 2 is 15V, both of which are consistent with the request information.

[0037] In this embodiment, a hardware circuit experimental platform is built, in which the energy base station is physically Fig. 9 As shown in the figure, the experimental results show that the energy packets received by each smart load are as follows: Fig.10 As shown, the energy pack voltage of smart load 1 is 25V, and the energy pack voltage of smart load 2 is 15V, both of which are consistent with the request information.

[0038] The present invention discloses a digital direct current transmission system and method based on coordinated scheduling of communication channels, which improves the effective energy ratio of energy packets, adopts independent communication channels to transmit control information, avoids additional information occupying energy packet space, and improves energy transmission efficiency; improves the stability of energy transmission, adopts digital discrete energy packet transmission and coordinated scheduling of communication channels, reduces voltage fluctuations, and ensures stable power supply; improves the flexibility of power scheduling, introduces an energy packet scheduling controller, realizes the interaction between the load side and the source side, and improves the accuracy and response speed of energy distribution; reduces power loss, improves long-distance transmission efficiency, optimizes energy packet modulation mode, reduces high-frequency signal loss, and improves long-distance power transmission capacity; solves the information interaction problem between the source side and the load side, adopts a two-way communication mechanism, enables the source side to dynamically adjust the energy packet output according to load demand, and realizes adaptive power supply; improves the reliability and adaptability of the system, transmits control information through independent communication channels, improves the stability of information transmission, and is suitable for various application scenarios such as microgrids and new energy.

[0039] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed in the present application should be covered within the protection scope of the present application.

Claims

1. A digital DC transmission system based on coordinated scheduling of communication channels, characterized in that: include: DC sources, energy base stations, smart loads, power transmission lines and communication channels; The DC source is used to provide DC power; The energy base station is used to receive DC power and generate and dispatch energy packets; The smart load is used to receive and process the transmitted energy packets, communicate and interact with the energy base station, make energy supply requests or feedback load status; The power transmission line is used to transmit energy packets between the energy base stations; The communication channel is used to coordinate the scheduling and transmission of energy packets between the energy base stations.

2. The digital DC transmission system based on communication channel coordinated scheduling according to claim 1 is characterized in that: The energy base station includes an energy distributor and an energy packet scheduling controller; The energy distributor is used to select a transmission path of the energy packet according to the control signal and transmit the energy packet to a designated location; The energy packet scheduling controller is used to issue control instructions for generating or scheduling energy packets according to power demand and transmission status.

3. The digital DC transmission system based on communication channel coordinated scheduling as claimed in claim 2, characterized in that: The energy distributor is composed of a multi-port power electronic converter based on a fully-controlled power electronic device, wherein the fully-controlled power electronic device includes a device made of silicon carbide and gallium nitride wide bandgap materials.

4. The digital DC transmission system based on communication channel coordinated scheduling as claimed in claim 3, characterized in that: The energy packet scheduling controller includes a sampler, a first communication module and a controller; The sampler is used to collect the transmission status of the power grid in real time and assist in the accurate dispatch of energy packets; The first communication module is used for information communication between the energy base station and the smart load, the energy base station and the DC source, and the energy base stations and the energy base stations; The controller is used to issue control instructions for generating or scheduling energy packets according to the information returned by the sampler and the first communication module.

5. The digital DC transmission system based on communication channel coordinated scheduling according to claim 1, characterized in that: The intelligent load includes a buffer, a second communication module and a load device; The buffer is used for smooth reception of energy packets; The second communication module is used for interaction between the smart load and the energy base station and real-time feedback of load demand information; The load device is used to receive the energy packet.

6. The digital DC transmission system based on communication channel coordinated scheduling as claimed in claim 5, characterized in that: The buffer is a super capacitor or a battery.

7. The digital DC transmission system based on communication channel coordinated scheduling according to claim 1 is characterized in that: The communication channel is carried out by wired transmission or wireless transmission.

8. A method for a digital DC transmission system based on coordinated scheduling of communication channels, characterized in that: For implementing the system according to any one of claims 1 to 7, the method comprises: S1. The smart load accesses the energy base station and uploads the corresponding load information, thereby generating a smart load request information queue and determining the transmission order of the energy packet; S2, the smart load makes an energy request; S3, the energy base station on the smart load side identifies the energy request information of the first queue, and if there is an energy request, transmits the energy request to the energy base station on the DC source side through the communication channel, and sets the request flag bit of the port corresponding to the smart load in the energy packet scheduling controller on the smart load side, which is used to subsequently determine whether the transmission channel is open. If there is no energy request, execute S8; S4, the DC source side energy base station receives the information and generates the capability package required by the smart load, and transmits it through the power transmission line; S5, the sampler in the energy base station on the smart load side monitors the power grid state. If there is no energy packet transmission or there is energy packet transmission for non-corresponding smart loads, then continue to execute S5. If there is energy packet transmission required by the corresponding smart load, then execute S6; S6, check whether the request flag bit of the port corresponding to the intelligent load is set, if not set, execute S5, if set, execute S7; S7, the energy base station on the smart load side opens the transmission channel to transmit the energy packet to the smart load at the corresponding port, and the smart load receives the energy packet after being smoothed by the buffer; S8. The sampler in the energy base station on the smart load side monitors the power grid status. If there is energy packet transmission required by the corresponding load, continue to execute S7. If there is no energy packet transmission, close the transmission channel, reset the request flag of the corresponding port of the smart load, and determine whether the request information is submitted by the last smart load in the queue. If not, execute S3 to respond to the energy request of the next load. If so, execute S2.

9. The digital direct current transmission method based on communication channel coordinated scheduling according to claim 8, characterized in that: The load information includes the address, voltage level and power level of the intelligent load.

10. The digital direct current transmission method based on communication channel coordinated scheduling according to claim 8, characterized in that: The energy request includes the address of the intelligent load, the address of the requested DC source, and the time and amount of the required energy.

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