Distributed mobile energy guarantee management device and method and vehicle

Abstract

The invention provides a distributed mobile energy guarantee management device and method and a vehicle, and a controller in the device determines a power supply for emergency power supply according to a working mode of the device in a current emergency power supply scene; if the power supply is the internal energy storage or external distributed power supply, the direct current output by the power supply is converged to the direct current bus, then the direct current is converted into alternating current by the inverter, the alternating current is boosted by the isolation transformer, and the alternating current is output to the power supply. The boosted alternating current is output to an external load through the alternating current bus; and if the power supply is an external alternating current power supply, boosting the alternating current output by the power supply through the isolation transformer, and outputting the boosted alternating current to an external load through the alternating current bus. The distributed mobile energy guarantee management device can realize uninterrupted power supply guarantee work and better adapt to various emergency power supply scenes, so that power supply can be recovered flexibly and quickly.

Description

Technical Field

[0001] The present invention relates to the technical field of distributed power distribution networks and microgrids, and in particular to a distributed mobile energy security management device, method and vehicle. Background Art

[0002] For some important conferences, events and precision equipment processing plants, once a short-term power outage occurs in the distribution line, it will cause significant impact and economic losses. Specifically, on the one hand, some important occasions such as government agencies, large hospitals, conferences, etc. have extremely high requirements for power supply continuity. Once a power outage occurs in these places, the consequences will be disastrous. On the other hand, when the distribution network line is inspected and repaired, faults and defects are handled, the method of first power outage and then power reversal is usually adopted, which will cause a long power outage and seriously affect the normal production and life of the enterprises and users involved. At the same time, when natural disasters occur, the continuous power supply capacity of the power grid will also be challenged, especially in southern my country where typhoon natural disasters often occur and earthquakes occur in some areas. If the above power supply is not guaranteed by emergency power supply, instantaneous or long-term power outages will cause great economic losses to society and individuals. Therefore, emergency power supply technology is of great significance to the safe operation of the power grid. For this reason, the emergency plan for urban distribution networks, which is mainly based on diesel-driven power supply vehicles, and the use of emergency power supply systems have become an important means for the reliable operation of distribution networks.

[0003] The disadvantages of conventional diesel generators are high pollution and noise. The time required from startup to stable power output is relatively long, making it difficult to achieve uninterrupted power supply and adapt to a variety of emergency power supply scenarios, which affects the flexible and rapid restoration of power supply. Summary of the invention

[0004] In order to overcome the above-mentioned defects that conventional diesel generators are difficult to achieve uninterrupted power supply, difficult to adapt to various emergency power supply scenarios, and affect the flexible and rapid restoration of power supply, the present invention provides a distributed mobile energy security management device, including: a controller, a DC bus, an inverter, an isolation transformer, an AC bus, and internal energy storage; the controller and the internal energy storage are connected to the DC bus, and the DC bus, the inverter, the isolation transformer and the AC bus are connected in sequence;

[0005] The controller determines the power source for emergency power supply according to the working mode of the device in the current emergency power supply scenario; if the power source is the internal energy storage or the external distributed power source, the DC power output by the power source is converged to the DC bus, and then the inverter converts the DC power into AC power, the isolation transformer boosts the AC power, and the boosted AC power is output to the external load through the AC bus; if the power source is an external AC power source, the AC power output by the power source is boosted by the isolation transformer, and the boosted AC power is output to the external load through the AC bus.

[0006] Optionally, if the working mode of the device is a standalone working mode, the power source is the internal energy storage;

[0007] If the working mode of the device is a networking working mode, the power source is an external distributed power source, and the distributed power source includes one or more of a diesel generator, a photovoltaic power source, and a hydrogen power source;

[0008] If the working mode of the device is a grid-connected working mode, the power source is an external AC power source, and the AC power source includes a power grid.

[0009] Optionally, it further comprises a plurality of diesel generator interfaces; one of the diesel generator interfaces is connected to the DC bus to form a converter main circuit;

[0010] The multiple diesel generator interfaces are used to connect to diesel generators of different power levels.

[0011] Optionally, the main circuit of the converter also includes a circuit breaker, a filter, a pre-charging unit, and a power unit; the circuit breaker, the filter, and the power unit are sequentially connected between the diesel generator interface and the DC bus, and the filter and the power unit are connected in parallel with the pre-charging unit.

[0012] Optionally, multiple load interfaces are also included;

[0013] The multiple load interfaces are used to connect loads of different levels.

[0014] Optionally, it also includes a circuit breaker and a cable winch connected between the load interface and the load.

[0015] Optionally, the controller is further used to collect operating information of the power supply and control the operating state of the power supply according to the operating state.

[0016] Optionally, the controller is specifically used to control the operating state of the power supply according to the operating state and a power dispatching instruction from the fusion terminal.

[0017] On the other hand, the present invention also provides a distributed mobile energy security management vehicle, characterized in that the distributed mobile energy security management device described in the first aspect is deployed on the vehicle.

[0018] Optionally, the load interface of the distributed mobile energy security management device is connected to the load through a circuit breaker and a cable winch.

[0019] Optionally, a copper busbar is deployed on the vehicle, and the copper busbar is used to connect the diesel generator to the distributed mobile energy security management device;

[0020] The wiring copper busbar includes an AC three-phase ABC lead, a neutral line N lead and a grounding PE lead.

[0021] On the other hand, the present invention further provides a distributed mobile energy security management method, which is applied to the distributed mobile energy security management device described in the first aspect, and the method includes:

[0022] The controller determines the power source for emergency power supply according to the working mode of the device in the current emergency power supply scenario;

[0023] If the power source is an internal energy storage or an external distributed power source, the controller converges the DC power output by the power source to the DC bus, so that the inverter converts the DC power into AC power, the isolation transformer boosts the AC power, and the boosted AC power is output to the external load through the AC bus;

[0024] If the power source is an external AC power source, the controller boosts the AC power output by the power source through an isolation transformer, so as to output the boosted AC power to an external load through an AC bus.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention provides a distributed mobile energy security management device and method, comprising: a controller determines the power supply for emergency power supply according to the working mode of the device in the current emergency power supply scenario; if the power supply is the internal energy storage or external distributed power supply, the DC power output by the power supply is converged to the DC bus, and then the inverter converts the DC power into AC power, the isolation transformer boosts the AC power, and the boosted AC power is output to an external load through the AC bus; if the power supply is an external AC power supply, the AC power output by the power supply is boosted through the isolation transformer, and the boosted AC power is output to an external load through the AC bus. The distributed mobile energy security management device of the present invention uses multiple types of power supplies that are compatible with the working mode in the current emergency power supply scenario for emergency power supply, which can achieve uninterrupted power supply work, better adapt to various emergency power supply scenarios, and thus flexibly and quickly restore power supply.

[0027] The present invention provides a distributed mobile energy security management vehicle, on which the above-mentioned distributed mobile energy security management device is deployed. The vehicle uses a variety of power sources that are compatible with the working mode in the current emergency power supply scenario through the distributed mobile energy security management device for emergency power supply, thereby achieving uninterrupted power supply and better adapting to various emergency power supply scenarios, thereby flexibly and quickly restoring power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the distributed mobile energy security management device of the present invention;

[0029] Figure 2 It is a structural schematic diagram of the distributed mobile energy security management device of the present invention;

[0030] Figure 3 It is a structural schematic diagram of the distributed mobile energy security management device of the present invention;

[0031] Figure 4 It is a schematic diagram of the internal layout of the distributed mobile energy security management device of the present invention;

[0032] Figure 5 A topological connection diagram of a distributed mobile energy security management device of the present invention;

[0033] Figure 6 It is a schematic diagram of internal communication of the distributed mobile energy security management device of the present invention;

[0034] Figure 7 A schematic diagram of the control flow of the distributed mobile energy security management device of the present invention;

[0035] Figure 8This is a schematic diagram of the structure of the distributed mobile energy security management vehicle of the present invention;

[0036] Fig. 9 It is a flow chart of the distributed mobile energy security management method of the present invention. DETAILED DESCRIPTION

[0037] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings.

[0038] Embodiment 1:

[0039] The present invention provides a distributed mobile energy security management device, such as Figure 1 As shown, it includes: a controller, a DC bus, an inverter, an isolation transformer, an AC bus, and internal energy storage; the controller and the internal energy storage are connected to the DC bus, and the DC bus, the inverter, the isolation transformer, and the AC bus are connected in sequence;

[0040] The controller determines the power source for emergency power supply according to the working mode of the device in the current emergency power supply scenario; if the power source is internal energy storage or external distributed power source, the DC power output by the power source is converged to the DC bus, and then the inverter converts the DC power into AC power, the isolation transformer boosts the AC power, and the boosted AC power is output to the external load through the AC bus; if the power source is an external AC power source, the AC power output by the power source is boosted through the isolation transformer, and the boosted AC power is output to the external load through the AC bus.

[0041] Emergency power supply technology is of great significance to the safe operation of the power grid. Whether it is disaster prevention and relief for natural disasters, rapid rescue, temporary power supply for special needs, or power supply guarantee for major events and other scenarios, requirements are put forward for rapid response, flexible power supply, and stable and durable emergency guarantee under the new power system. However, the traditional emergency power supply represented by diesel generators is difficult to meet the current emergency guarantee needs in multiple scenarios. First, the diesel energy source is single and the power supply durability is insufficient. Second, the response speed, load capacity, stability and flexibility of the generator set are poor. Third, the unit noise and emission pollution are large. Therefore, in an embodiment of the present invention, a distributed mobile energy security management device is provided. The device uses multiple types of power supplies that are compatible with the working mode in the current emergency power supply scenario for emergency power supply, which can achieve uninterrupted power supply work and better adapt to various emergency power supply scenarios, so as to flexibly and quickly restore power supply.

[0042] Figure 1 The blue in the middle represents direct current, and the red represents alternating current, which is an inverter DC (Direct Current) / AC (Alternating Current) converter.

[0043] In different emergency power supply scenarios, the device can use different working modes and corresponding power supplies to perform uninterrupted power supply. For example, if the working mode of the device is a stand-alone working mode, the power supply is internal energy storage. If the working mode of the device is a networking working mode, the power supply is an external distributed power supply, and the distributed power supply includes one or more of a diesel generator, a photovoltaic power supply, and a hydrogen power supply. If the working mode of the device is a grid-connected working mode, the power supply is an external AC power supply, and the AC power supply includes a power grid. Optionally, the external AC power supply may also include an external AC energy storage. In other words, the device can complete independent power supply, can be networked and aggregated with other types of power supply energy to build a power supply system to complete network power supply, and can also be connected to the power grid to complete grid-connected power supply. When independently powered, multiple forms of energy can be independently powered, which is more flexible and efficient. When networked power supply is used, multiple forms of energy can be coordinated for power supply, which is more durable and stable. In some cases, multiple systems flexibly provide networking and communication guarantees to achieve regional power restoration. The relevant content of communication guarantee will be explained later.

[0044] In the first implementation method, the diesel generator parallel operation is realized on the DC bus and the energy storage parallel operation is realized on the AC bus. The diesel generator AC parallel operation process is further simplified.

[0045] The electrical structure in this implementation has the following innovations:

[0046] (1-1) Power module configuration design:

[0047] The device may also include multiple diesel generator interfaces; one diesel generator interface is connected to the DC bus to form a converter main circuit. Multiple diesel generator interfaces are used to connect to diesel generators of different power levels. In combination with the common power levels and weight specifications of current diesel generators, the device provides multiple diesel generator interfaces for connecting to diesel generators of different power levels. Multiple diesel generator interfaces can be set as plug-and-play interfaces. Through the diesel generator interfaces, multiple diesel generators can be connected to the DC bus ( Figure 1 The example in the figure is a 750V DC bus). Optionally, the DC bus is connected to the AC grid and the AC load through an inverter (such as an inverter). This functional module configuration design method can achieve plug-and-play access and capacity expansion of diesel generators and energy storage of different models and capacities.

[0048] In addition, the device may also include an AC port for energy storage access, and external AC energy storage is connected to the device through the AC port.

[0049] For example, Figure 1As shown, when multiple diesel generators are connected through the diesel generator interface, each diesel generator interface can be connected to an AC / DC converter, such as a rectifier, to access the DC bus. Photovoltaic systems (i.e. photovoltaic power sources) and hydrogen energy systems (i.e. hydrogen power sources) can be connected to the DC bus through DC / DC converters (or DC ports). External AC energy storage can be connected to different energy storage PCS (Power Conversion System, energy storage converter) access devices. Different energy storage PCS can be connected as follows: Figure 1 The connected energy storage PCS1 and the connected energy storage PCS2 are shown in FIG. Through the configuration of the power module, the efficient coordinated utilization of distributed power sources such as photovoltaic and hydrogen energy can be achieved.

[0050] In this implementation, the device acts as a distributed mobile energy unit system, such as Figure 2 As shown, the converter main circuit also includes a circuit breaker, a filter, a pre-charging unit, and a power unit; the circuit breaker, the filter, and the power unit are sequentially connected between the diesel generator interface and the DC bus, and the filter and the power unit are connected in parallel with the pre-charging unit. Figure 2 In the system, the main circuit of the converter includes components such as circuit breakers, filters, pre-charging units, power units, and DC bus units. The circuit breaker controls the disconnection state of the main circuit, and mainly realizes the disconnection of the electrical connection between the converter system of the plug-and-play power supply system and the power grid, which is convenient for system maintenance and overhaul. The filter can be an LCL filter unit, which is a transitional filter circuit. The LCL filter unit is designed in the converter of the distributed mobile energy power supply system to effectively filter out the high-frequency harmonic current generated by the converter in the system unit, suppress the impact current in the main circuit, and improve the system operation reliability. In addition, in Figure 2 In the embodiment, a circuit breaker, a filter, and a power unit are sequentially connected between the DC / DC port of the DC load and the DC bus, and a circuit breaker, a filter, and a power unit are sequentially connected between the DC / DC port of the photovoltaic system and the DC bus.

[0051] (1-2) Interface configuration design:

[0052] The device may also include multiple load interfaces; the multiple load interfaces are used to connect loads of different levels. The load interface is an AC port, and the load is Figure 1For AC loads in the AC port, when the AC port supplies power to the load, the total power provided can be equipped with load classification function as needed. Each level of load can be connected through a controllable circuit breaker when connected to the load interface. Take the load level including primary load, secondary load and tertiary load as an example. Three controllable circuit breakers are connected to the primary load, secondary load and tertiary load respectively, and the power supply of important loads is guaranteed first. Primary loads are usually important railway hubs, communication hubs, important international event venues, important hotels, hospital operating rooms, satellite ground stations, civil airports, bank securities trading centers, important biological laboratories, etc. Secondary loads are usually such as prefecture-level and municipal government office buildings, three-star hotels, Class A cinemas, prefecture-level and municipal major libraries, museums, cultural relics and treasures warehouses, etc. Except for primary loads and secondary loads, all others belong to tertiary loads.

[0053] Optionally, the device further comprises a circuit breaker and a cable winch connected between the load interface and the load.

[0054] (1-3) Port function design to achieve AC / DC hybrid power supply:

[0055] 1) AC port isolation transformer:

[0056] The device can be configured in the form of a mobile energy storage box, and the internal space of the device (such as the inside of the box) is equipped with a low-voltage distribution cabinet, a PCS converter cabinet, a diesel generator access inverter cabinet, and an AC port isolation transformer. The low-voltage distribution cabinet may include Figure 1 The DC power distribution interface module, namely the DC / DC port, supplies power to the DC load. The PCS converter cabinet may include Figure 1 The diesel generator connected to the inverter cabinet can include: Figure 1 The AC / DC converter (i.e., AC / DC converter) shown in FIG. is used to connect multiple diesel generators. The AC port isolation transformer may include Figure 1 The isolation transformer shown is used to connect multiple AC loads of different levels.

[0057] 2) Energy storage port:

[0058] An energy storage battery cabinet is provided, including a charging and discharging DC / DC module, a lithium-ion battery system, a BMS (Battery Management System), a temperature control system and a fire protection system, a UPS (Uninterruptible Power Supply), etc. UPS can be an example of internal energy storage.

[0059] 3) DC charging interface:

[0060] A unidirectional isolated DC charging interface is provided. The input side of the DC charging interface is connected to a 750V DC bus, and the output side voltage is dynamically controllable. A unidirectional isolated DC charging pile is provided, and a single gun is connected. The DC charging interface can be a DC / DC port, which is used to connect a DC load and supply power to the DC load.

[0061] 4) Mobile photovoltaic power supply vehicle interface (also called distributed photovoltaic interface):

[0062] Distributed photovoltaic interface access system, including DC / DC module access to 750V DC bus, photovoltaic communication access interface. This interface is used to access photovoltaic power supply as a distributed power supply for emergency power supply.

[0063] In the second implementation, Figure 3 As shown, the device includes a control area 1 and an energy storage area 2. The control area 1 is provided with a control cabinet 11, a junction cabinet 12, a PCS inverter 13, an isolation transformer 14, and a heat sink 15 (optional). The junction cabinet 12 includes a DC / DC port 121 and an AC / DC converter 122, and the control area 2 is provided with a battery cabinet 21. The schematic diagram and topological connection diagram of the device in this implementation are shown in FIG. Figure 4 and 5 As shown, the control cabinet 11 is connected to the combiner cabinet 12 through a line, the combiner cabinet 12 is connected to the input end of the PCS inverter 13 through a line, and the battery cabinet 21 in the energy storage area 2 is connected to the combiner cabinet 12 through a line.

[0064] In this implementation, the diesel generator or diesel generator car only needs to be connected to the junction box 12 through the AC / DC converter 122 to convert the AC power output by the diesel generator or diesel generator car into DC power and merge it into the junction box 12. After the power is merged through the junction box 12 by the control cabinet 11, it reaches the PCS inverter 13 through the line, and then the PCS inverter 13 converts the power and outputs it in the form of AC power. Finally, the voltage is increased to 400V through the isolation transformer 14 to provide temporary power for the user load of the community. That is, in this implementation, the PCS inverter 13 has the same function as the AC / DC converter in the first implementation, the AC / DC converter 122 in this implementation has the same function as the DC / AC converter in the first implementation, and the junction box 12 in this implementation has the same function as the DC bus in the first implementation. It can be seen that the electrical structure complexity of the first implementation is lower than the electrical structure of the diesel generator AC parallel machine in the second implementation.

[0065] In some scenarios, if it is impossible to dispatch energy storage vehicles, battery vehicles and hydrogen fuel cell vehicles during power grid maintenance operations, Figure 3 to Figure 5The device shown (which can be embodied in the form of a mobile energy storage vehicle) and a diesel generator or a diesel generator vehicle are combined into a DC power system, and the mobile energy storage vehicle is used as the control center of the AC and DC. When the device is powered alone, it can form an isolated network and provide a constant voltage to the load to ensure the normal operation of the load until the maintenance work is completed. In addition, considering the variability of the on-site situation, a cable cabinet 15 can be placed in the control area 1, so that the operator can use the cables in the cable cabinet 15 according to the situation. If the battery cabinet 21 adopts the form of an air-cooled battery cabinet, the battery cabinet 21 and all the equipment in the control area 1 can be assembled into a container; if the battery cabinet 21 adopts the form of a liquid-cooled battery cabinet, since the liquid-cooled battery cabinet is self-contained and its own waterproof and sun-proof properties have reached outdoor standards, it can be installed separately from all the equipment in the control area 1, and all the equipment in the control area 1 can be assembled into a container, and the battery cabinet 21 can be placed between the container and the front of the vehicle. Alternatively, all the equipment in the control area 1 of the battery cabinet 21 can be assembled into a container. The battery in the battery cabinet 21 is a lithium iron phosphate battery because the lithium iron phosphate battery has a long service life, high temperature resistance, fast charging, and is green and environmentally friendly. The control cabinet 11 is equipped with an RTU (Remote Terminal Unit) device to monitor and control the energy storage vehicle also equipped with an RTU device for easy management.

[0066] The second implementation method can be used to expand the capacity of the same emergency power supply system in parallel to meet different emergency power supply needs. However, due to the diversity of emergency power supply scenarios and the different manufacturers and models of the current stock of diesel generators, the plug-and-play emergency power supply system that can integrate multiple capacity levels provided by the first implementation method can adapt to the flexible access of various distributed energy sources for power supply. Compared with the second implementation method, the first implementation method can adapt to a variety of emergency scenarios, and can not only realize the plug-and-play of different types of existing diesel generator sets to improve utilization, but also realize the function of flexible and rapid access of various distributed emergency power supplies to the distribution network to restore power supply.

[0067] In addition to providing the above electrical structure, the embodiment of the present invention also provides a communication solution, which can realize regional power restoration, specifically, it can realize functions such as mobile fast self-organizing network, high real-time emergency communication, remote dispatch command, etc. The controller is also used to collect the operation information of the power supply and control the operation status of the power supply according to the operation status. Figure 6As shown, the energy management system can provide RS-485 interface and Ethernet interface to collect data from all energy storage (such as energy storage PCS) and diesel generator interface units, and unify real-time control. Inside the device, the controller as the power supply system controller can collect the operating status of the inverter device (such as DC / AC port or AC / DC port) and the diesel generator unit through the 485 bus, and input and output voltage, current, power and other operating information.

[0068] Since the existing diesel generator communication schemes and protocols are not unified, it is difficult to communicate with the diesel generator to control the output power of the diesel generator. Therefore, the diesel generator can be used as a voltage source and the AC / DC module as the load of the diesel generator. By controlling the power of the AC / DC module, the power of the diesel generator can be controlled without communicating with the diesel generator.

[0069] In addition Figure 6 In the example, the controller can specifically control the operating state of the power supply according to the operating state and the power dispatching instructions from the fusion terminal. The power dispatching instructions of the fusion terminal can be sent by the energy management system. The energy management system responds to the instructions of the power dispatching system and forwards the instructions to the fusion terminal through the server, the Internet, and GPRS (General Packet Radio Service). After receiving the control instructions from the fusion terminal, the controller controls the diesel generator unit and the energy storage to act accordingly. The GPRS example can include 5G+ satellite communication functions. When extreme disaster events cause damage to power supply and communication facilities, this communication method can accept remote dispatching management of the power grid, and can quickly ensure power supply and restore communications.

[0070] In order to achieve distributed mobile energy security and management, the embodiment of the present invention further provides a flexible system operation strategy, which can be implemented by the controller.

[0071] The plug-and-play system AC / DC bidirectional conversion power electronic device (i.e., the device) can realize AC / DC bidirectional conversion, and can operate under the required working conditions by selecting the working mode, setting the voltage, current, and power parameters, so as to meet the user's control requirements for DC voltage, operating power, and output current. Specifically, the controller controls the voltage, power, and current of the power supply output for emergency power supply by controlling converters such as inverters or rectifiers according to the current working mode and the various target parameters required in the current emergency power supply scenario, so as to meet the target parameters and obtain the user's control requirements.

[0072] In one possible way, the device has multiple control modes such as reactive / active control, power factor control, V / F (voltage / frequency, voltage-frequency ratio control), that is, the grid-connected port converter of energy storage and diesel generator connected to the AC power grid should have PQ (Power-Quality, active and reactive) mode, VF mode (droop or VSG (Virtual Synchronous Generator, virtual synchronous machine)) and power quality management function, among which the PQ mode is used for grid-connected conditions, and the active and reactive power are dispatched by the energy management system; the VF mode is mainly used for off-grid conditions, simulating the voltage / frequency characteristics of the actual power grid to make the system more stable. In this way, the controller can realize the output parameters of the power supply by adopting the control method corresponding to the current emergency power supply scenario, thereby realizing emergency power supply for the current emergency power supply scenario. Specifically, the remaining capacity of the grid-connected port can also be used for power quality management to improve the utilization rate of equipment capacity.

[0073] The device can realize multi-machine parallel operation without communication and cluster parallel operation with communication.

[0074] The device also has complete protection functions such as AC / DC leakage current, overcurrent, anti-islanding protection, power module failure, overtemperature, lightning protection, reverse polarity of DC input, DC overvoltage / undervoltage, etc. It can communicate with the master station to realize remote control, and realize adjustable working mode and operating parameters at the master station. The communication method is realized in the form of corresponding port conversion RS-485.

[0075] The controller can adopt DSP (Digital Signal Processing) + FPGA (Field Programmable Gate Array) control unit. The system has fast response speed, high accuracy, diversified measurement parameters, and plug-and-play power supply system converter. It uses power electronic conversion technology to realize bidirectional energy flow, absorb energy from the power grid and transmit it to the DC side to realize controllable rectification; when the DC side of the microgrid converter is connected to the photovoltaic system and energy storage system, the AC power that meets the national standards is fed back to the AC grid after being inverted and output by the microgrid converter.

[0076] The device is installed outdoors as a plug-and-play power supply system converter, and the cable inlet and outlet must be down-inlet and down-outlet. This part will be explained in the subsequent embodiments.

[0077] As a diesel generator parallel system, the device has a 750V DC bus and a rectifier that connects the diesel generator to the 750V DC bus in addition to the grid-connected port. The rectifier adopts a modular design and can be applied to diesel generators of various power levels. The rectifier works like an AC electronic load, absorbing controllable active power from the diesel generator and transferring the energy to the DC bus. The power size is controlled by the energy management system. This solution avoids the complex process of traditional diesel generator AC paralleling and innovatively proposes a solution to achieve diesel generator paralleling from the DC bus.

[0078] The energy storage converter (PCS) has a faster dynamic response than the diesel generator. The energy storage and its PCS connected to the 380V AC grid can expand the capacity and quickly stabilize the 380V AC bus voltage.

[0079] The 750V DC bus is a key link in the diesel generator parallel system. Maintaining the basic stability of its voltage is the basic premise for the stable operation of the entire system. In PQ mode, the 750V DC bus voltage is mainly controlled by the inverter of the diesel generator part; in VF mode, the 750V DC bus voltage is mainly controlled by the rectifier connecting the diesel generator and the 750V DC bus; the 750V DC bus is also connected to the energy storage, which uses its fast dynamic response characteristics to assist in stabilizing the 750V DC bus voltage.

[0080] For example, the control flow of the device is as follows Figure 7 As shown, it is possible to realize functions such as planned islanding judgment, grid fault judgment, grid recovery judgment, planned islanding process, fault islanding process, grid recovery process, grid-connected operation mode and expected islanding operation mode, so as to provide high-quality power supply services, including the following processes:

[0081] Step 1: The controller determines whether an island is planned; if yes, it goes to step 4; if no, it goes to step 2;

[0082] Step 2: Determine whether there is a power grid fault; if yes, go to step 5; if no, go to step 3;

[0083] Step 3: Execute the grid-connected operation mode and return to step 1 to continue the judgment.

[0084] Step 4: Execute the planning island process and proceed to step 6;

[0085] Step 5: Execute the fault process and proceed to step 6;

[0086] Step 6: Execute the island operation mode and proceed to step 7:

[0087] Step 7: Determine whether the power grid has recovered; if so, proceed to step 8; if not, return to step 6 to continue the island operation mode;

[0088] Step 8: Execute the grid-connected recovery process and return to step 3 to continue the grid-connected operation mode.

[0089] Combined with the above Figure 7 The specific implementation process of the above steps is shown in the following description:

[0090] (1) Normal grid-connected operation mode of the mains:

[0091] The basic idea of ​​hierarchical control is adopted.

[0092] The inverter and energy storage PCS of the diesel generator part mainly operate in PQ mode, and the active and reactive power are dispatched by the upper energy management system. The local energy management system makes reasonable power distribution based on the remaining diesel, the power of the energy storage battery pack and its power.

[0093] The local energy management system relies on historical data and current data information provided by the grid current sensor to smooth out grid current fluctuations and reduce peak loads; and the power quality management function uses the remaining capacity of the grid-connected port to manage power quality.

[0094] The energy management system has SOC management for the energy storage battery. When the SOC of the energy storage battery is lower than 30%, discharging is stopped; when the SOC of the energy storage battery is higher than 90%, charging is stopped.

[0095] The VF mode control code is also always running, and when a mains power fluctuation is detected, it is used to immediately stabilize the voltage and frequency of the local power grid.

[0096] (2) Mains failure process:

[0097] If the city power fails due to a fault, the local energy management system will immediately operate the load switch group after detecting the grid fault, disconnect it from the grid in time, and give priority to ensuring the power supply of the primary load. The secondary and tertiary loads will be reasonably arranged according to the remaining capacity and the power supply plan.

[0098] During this process, the inverter device and energy storage PCS of the diesel generator part are mainly controlled in VF mode to ensure the basic stability of the internal 380V AC bus. The local energy management system allocates the output power of each device according to its capacity.

[0099] (3) Planned islanding process for city power maintenance:

[0100] If the city power needs to be shut down for maintenance, the local energy management system has a load transfer function for planned maintenance. According to the current size of the grid-connected current, it automatically adjusts the active and reactive output of the inverter device of the diesel generator part and the energy storage PCS, gradually reducing the current of the grid. The energy consumption of the load will be mainly provided by this system. At this time, if the grid is shut down, a smooth switching of the system operation mode can be achieved.

[0101] (4) Island operation mode when the mains power is cut off:

[0102] After the mains power is cut off due to failure or maintenance, the inverter device of the diesel generator part and the energy storage PCS maintain VF mode control, and the two work together to supply power to the load; the energy management system makes reasonable power distribution based on the remaining diesel, the power of the energy storage battery pack and its power size.

[0103] (5) Grid connection recovery process after the mains power supply is restored:

[0104] When the mains power returns to normal, the energy management system restores the grid connection through system pre-synchronization adjustment, and switches the diesel generator and energy storage to different working modes as needed. During the switching process of different modes, the modules inside the system can coordinate well, and the DC bus voltage remains stable. The diesel generator or inverter device must keep at least one line online to maintain the stability of the bus voltage.

[0105] In the embodiment of the present invention, a mobile energy storage emergency power supply system based on the combination of mains power and energy storage battery realizes pollution-free and uninterrupted power supply for emergency power supply. For example, a lithium iron phosphate battery can be selected, and a lithium battery mathematical model can be established based on the Thevenin circuit characteristics of the lithium battery, and a three-stage charging and an overall charging and discharging control scheme of the energy storage battery based on the working range of the battery charge state are adopted. The mains side converter adopts constant power control. The load side converter directly provides electrical energy to the load, and adopts constant voltage and constant frequency control to ensure that the system provides stable and high-quality electrical energy. It also provides energy management and coordinated control processes based on system power balance, and energy management and control processes under mains operation, mains failure and comprehensive modes.

[0106] The embodiments of the present invention can effectively solve the plug-and-play problem of existing diesel generators of different manufacturers and models, and flexibly expand the capacity and network. In addition, it integrates plug-and-play interfaces for energy storage vehicles of different capacities and models, other distributed energy sources, and AC / DC hybrid power supply, so that the system can be adapted to the needs of various emergency scenarios, effectively extend the power supply time and quality, enable the idle diesel generators to be flexibly combined and operated, improve utilization, and realize emergency power supply guarantee work with high quality.

[0107] The embodiment of the present invention can be adapted to different models of diesel generators and energy storage vehicles of different capacities, with modular power unit design, flexible expansion, and plug-and-play interface design for flexible networking. The integrated energy security and energy management system can access a variety of distributed energy sources, integrate AC / DC hybrid power supply, accept remote control and management of the power grid, and improve the quality of power supply.

[0108] Embodiment 2:

[0109] Based on the same inventive concept, the present invention also provides a distributed mobile energy security management vehicle, on which the distributed mobile energy security management device described in the above embodiment is deployed.

[0110] In one possible implementation, the vehicle selects a standard truck and matches it with a distributed mobile energy security management device based on the size of the entire system, the types of related vehicles currently on the market, and economic considerations. The device can be a distributed mobile energy system deployed in the vehicle in the form of a modular unit.

[0111] The vehicle interior includes the incoming line cabinet, the converter cabinet of the distributed system, and the inverter cabinet for diesel generator access. Figure 8 For example, the vehicle includes multiple inverter cabinets (inverter cabinets 1 to 5), a PCS cabinet, a distribution cabinet and an electric wire take-up device.

[0112] The inverter cabinet may be integrated with the inverter and isolation transformer in the above-mentioned distributed mobile energy security management device; the PCS cabinet may be integrated with the distributed power supply and DC energy storage outside the above-mentioned distributed mobile energy security management device; the power distribution cabinet may be integrated with the controller and internal energy storage in the above-mentioned distributed mobile energy security management device; the electric wire collector may be integrated with the lines between the various parts of the above-mentioned distributed mobile energy security management device, as well as optional reserved interfaces / reserved ports. It can be understood that in addition to being able to realize emergency power supply in the distributed mobile energy security management scenario, the line can also be used for other electronic devices other than the distributed mobile energy security management device, for example, it can power other electronic devices such as user terminals. Specifically, in order to adapt to different application scenarios, the line can include AC cables (usually 4 to 5 cable cores) and can also include DC cables (such as two positive and negative cable cores).

[0113] The load interface of the distributed mobile energy security management device is connected to the load through a circuit breaker and a cable winch. Specifically, the port of the inverter cabinet can be connected to the AC load, and the cable winch is connected between the AC load and the inverter cabinet. One end of the cable winch is connected to the intelligent circuit breaker, and the other end is connected to the load for output. The other end of the intelligent circuit breaker is connected to the load interface. The diesel generator access adopts a fast interface form, and the protection level after plugging is IP67.

[0114] The vehicle is equipped with a copper busbar, which is used to connect the diesel generator to the distributed mobile energy security management device; the copper busbar includes AC three-phase ABC leads, N (neutral) leads and PE (Protective Earth) leads. For example, the diesel generator is connected to the inverter cabinet using the lower inlet / lower outlet inlet and outlet method; the AC side cabinet is used as an inverter cabinet and is provided with a copper busbar; the cabinet is designed with the copper busbar inlet and outlet as follows: the AC side main circuit wiring is a three-phase A / B / C / N (neutral) and PE five-way lead access quick interface, and the PE line is connected to the cabinet as a protective grounding copper busbar inside the cabinet and connected to the shell; the DC side main circuit wiring is positive and negative two-way leads, and each lead cable is connected to the copper busbar; the DC side main circuit wiring is positive and negative two-way leads, and each lead is connected to the copper busbar by a cable.

[0115] Embodiment 3:

[0116] Based on the same inventive concept, the present invention also provides a distributed mobile energy security management method, which is applied to the distributed mobile energy security management device of the above embodiment. The flow chart is as follows: Fig. 9 As shown, including:

[0117] Step 901: The controller determines the power source for emergency power supply according to the working mode of the device in the current emergency power supply scenario.

[0118] Step 902: If the power supply is an internal energy storage or an external distributed power supply, the controller converges the DC power output by the power supply to the DC bus, so that the inverter converts the DC power into AC power, the isolation transformer boosts the AC power, and outputs the boosted AC power to the external load through the AC bus; if the power supply is an external AC power supply, the controller boosts the AC power output by the power supply through the isolation transformer, so as to output the boosted AC power to the external load through the AC bus.

[0119] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0120] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0121] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0122] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, but these changes, modifications or equivalent substitutions are all within the protection scope of the claims to be approved.

Claims

1. A distributed mobile energy security management device, characterized in that: include: Controller, DC bus, inverter, isolation transformer, AC bus, internal energy storage; the controller and the internal energy storage are connected to the DC bus, and the DC bus, the inverter, the isolation transformer and the AC bus are connected in sequence; The controller determines the power source for emergency power supply according to the working mode of the device in the current emergency power supply scenario; if the power source is the internal energy storage or the external distributed power source, the DC power output by the power source is converged to the DC bus, and then the inverter converts the DC power into AC power, the isolation transformer boosts the AC power, and the boosted AC power is output to the external load through the AC bus; if the power source is an external AC power source, the AC power output by the power source is boosted by the isolation transformer, and the boosted AC power is output to the external load through the AC bus.

2. The device according to claim 1, characterized in that If the working mode of the device is the independent working mode, the power source is the internal energy storage; If the working mode of the device is a networking working mode, the power source is an external distributed power source, and the distributed power source includes one or more of a diesel generator, a photovoltaic power source, and a hydrogen power source; If the working mode of the device is a grid-connected working mode, the power source is an external AC power source, and the AC power source includes a power grid.

3. The device according to claim 2, characterized in that It also includes a plurality of diesel generator interfaces; one of the diesel generator interfaces is connected to the DC bus to form a converter main circuit; The multiple diesel generator interfaces are used to connect to diesel generators of different power levels.

4. The device according to claim 3, characterized in that The inverter main circuit also includes a circuit breaker, a filter, a pre-charging unit, and a power unit; the circuit breaker, the filter, and the power unit are sequentially connected between the diesel generator interface and the DC bus, and the filter and the power unit are connected in parallel with the pre-charging unit.

5. The device according to any one of claims 1 to 6, characterized in that: Also includes multiple load interfaces; The multiple load interfaces are used to connect loads of different levels.

6. The device according to claim 5, characterized in that Also included is a circuit breaker and a cable winch connected between the load interface and the load.

7. The device according to claim 1, characterized in that The controller is further used to collect operating information of the power supply and control the operating state of the power supply according to the operating state.

8. The device according to claim 7, characterized in that The controller is specifically used to control the operating state of the power supply according to the operating state and the power dispatching instruction from the fusion terminal.

9. A distributed mobile energy security management vehicle, characterized in that: The vehicle is deployed with the distributed mobile energy security management device described in any one of claims 1 to 8.

10. The vehicle according to claim 9, characterized in that The load interface of the distributed mobile energy security management device is connected to the load through a circuit breaker and a cable winch.

11. The vehicle according to claim 10, characterized in that A copper busbar is deployed on the vehicle, and the copper busbar is used to connect the diesel generator to the distributed mobile energy security management device; The wiring copper busbar includes an AC three-phase ABC lead, a neutral line N lead and a grounding PE lead.

12. A distributed mobile energy security management method, characterized in that: Applied to the distributed mobile energy security management device according to any one of claims 1 to 8, the method comprises: The controller determines the power source for emergency power supply according to the working mode of the device in the current emergency power supply scenario; If the power source is an internal energy storage or an external distributed power source, the controller converges the DC power output by the power source to the DC bus, so that the inverter converts the DC power into AC power, the isolation transformer boosts the AC power, and the boosted AC power is output to the external load through the AC bus; If the power source is an external AC power source, the controller boosts the AC power output by the power source through an isolation transformer, so as to output the boosted AC power to an external load through an AC bus.

Images