Communication-based motorized micro-grid master-slave-free parallel control method

Abstract

The invention relates to a communication-based motorized micro-grid master-slave-free parallel control method, and belongs to the technical field of power electronic equipment control. A plurality of motorized micro-grids are connected in parallel to form a network, the motorized micro-grids are interconnected through a communication bus, and periodically sample and report voltage feedback values to other motorized micro-grids in a power supply network; calculating a mean value based on all reported voltage feedback, calculating voltage deviation based on a voltage feedback set value, generating adjustment power through a voltage inner ring and a current inner ring, outputting the adjustment power to a load, and when the load changes or the voltage set value of the maneuvering micro-grid changes, adjusting the adjustment power to load balance under the condition of ensuring stable power supply. The problem that power supply quality and power supply network reliability cannot be considered in the prior art is solved.

Description

Technical Field

[0001] This invention relates to the field of power electronic equipment control technology, and in particular to a communication-based masterless parallel control method for mobile microgrids. Background Technology

[0002] At present, new power supply equipment represented by mobile microgrids, UPS, and inverters are being used more and more widely. Compared with traditional power supply equipment such as diesel power stations, these power supply equipment can monitor and manage all power supply units in the power grid based on communication technology. They have many advantages such as modularity, flexible networking, uninterrupted power supply, and better environmental adaptability. However, due to factors such as cost and mobile transportation, the capacity of these equipment is generally not large. In practical applications, since the load power is often large, multiple power supply equipment are usually connected in parallel to increase the power supply capacity.

[0003] Taking mobile microgrids as an example, there are several existing parallel connection methods for mobile microgrids, including communication-based master-slave parallel connection and droop control parallel connection. Among them, the communication-based master-slave parallel connection is the most common and mature, with good power quality. However, if the mobile microgrid acting as the master fails or goes offline, it will cause the power supply system to fail and shut down, resulting in low parallel reliability. The droop control method without communication does not have a master, and it can continue to supply power when any one or more devices fail, resulting in high parallel reliability. However, the power supply voltage will change according to the load, resulting in poor power quality.

[0004] In summary, the inability of existing technologies to balance power quality and power network reliability has become a common problem for power supply equipment such as mobile microgrids, UPS, and inverters. Summary of the Invention

[0005] Based on the above analysis, the embodiments of the present invention aim to provide a communication-based masterless parallel control method for mobile microgrids, in order to solve the problem that the existing technology cannot solve in terms of balancing power supply quality and power network reliability.

[0006] On one hand, embodiments of the present invention provide a communication-based masterless parallel control method for mobile microgrids. A power supply network is formed by multiple mobile microgrids connected in parallel. Each mobile microgrid generates output power based on its received voltage setpoint and supplies power to the load based on the output power. The mobile microgrids are interconnected via a communication bus, reporting voltage feedback values ​​to other mobile microgrids within the power supply network through the communication bus. Each microgrid continuously adjusts its output power by periodically iteratively executing the following process, which specifically includes:

[0007] Read its own voltage deviation threshold and current limit threshold, and sample the current cycle voltage feedback value and current feedback value;

[0008] The current period voltage feedback value is reported through the communication bus, and the voltage feedback values ​​reported by other mobile microgrids in the power supply network in the current period are obtained.

[0009] The current cycle voltage feedback setpoint is calculated based on the current cycle voltage feedback value and the current cycle voltage feedback values ​​reported by other mobile microgrids in the power supply network.

[0010] The voltage deviation is calculated based on the current cycle voltage feedback setpoint and the voltage setpoint.

[0011] Determine whether the absolute value of the voltage deviation is less than the voltage deviation threshold; if so, set the voltage deviation to 0.

[0012] Otherwise, after adjusting the power based on the voltage deviation and outputting it, the next iteration is executed after a one-cycle interval.

[0013] The beneficial effects of the above technical solution are as follows: In a power supply network composed of multiple parallel mobile microgrids, each mobile microgrid periodically iterates through the process described in the above technical solution. Based on the communication bus, it obtains the voltage feedback values ​​of other mobile microgrids within the power supply network and calculates its own current-cycle voltage feedback setpoint with its own current-cycle voltage feedback value. This ensures that the voltage feedback of all mobile microgrids within the power supply network is as consistent as possible for the same cycle, avoiding instability caused by differences in the voltage feedback values ​​of each mobile microgrid. After calculating the voltage deviation, each mobile microgrid compares it with its own voltage deviation threshold. Voltage deviations less than its own voltage deviation threshold are set to 0, effectively reducing the regulation fluctuations of each mobile microgrid and improving power supply stability.

[0014] A further improvement to the above method is that the current cycle voltage feedback setpoint is calculated based on the current cycle voltage feedback value and the current cycle voltage feedback values ​​reported by other mobile microgrids in the power supply network. Specifically, the average current cycle voltage feedback value is calculated based on the current cycle voltage feedback values ​​of all mobile microgrids as the current cycle voltage feedback setpoint.

[0015] The beneficial effect of the above-mentioned further improvement scheme is that the average value method can be used to calculate the current cycle voltage feedback setpoint based on all the current cycle voltage feedback values.

[0016] Based on a further improvement of the above method, when the mobile microgrid within the power supply network fails to report the current cycle voltage feedback value, the current cycle voltage feedback setpoint is calculated using the following formula, which is specifically expressed as follows:

[0017] In the formula, U b It is the current cycle voltage feedback setpoint, Ublast It is the voltage feedback setpoint of the previous cycle, n is the number of mobile microgrids connected in parallel to the power supply network, and U bx It is the voltage feedback value reported by any other mobile microgrid within the power supply network during the current cycle.

[0018] The beneficial effect of the above-mentioned further improvement scheme is that, in the case where not all voltage feedback values ​​for the current cycle are obtained, the voltage feedback setting value for the current cycle can be calculated by applying the first-order filtering method based on the voltage feedback setting value of the previous cycle and the voltage feedback value reported by any other mobile microgrid in the power supply network for the current cycle.

[0019] A further improvement to the above method, specifically, obtaining the adjusted power based on the voltage deviation, includes:

[0020] The current setpoint is calculated based on the voltage deviation.

[0021] The current deviation is obtained based on the given current value and the current feedback value of the current cycle.

[0022] The PWM duty cycle is calculated based on the current deviation.

[0023] The power adjustment is obtained based on the voltage deviation, the current deviation, and the PWM duty cycle.

[0024] The beneficial effects of the above-mentioned further improvement scheme are: it can obtain the adjustment power to be output in the current cycle. The current setpoint calculated based on the voltage deviation is the output current corresponding to the voltage deviation. Furthermore, based on the current setpoint and the current feedback value of the current cycle, the current deviation can be obtained, which is the current value to be adjusted in the current cycle. Then, the PWM duty cycle is calculated based on the current deviation, and the adjustment power obtained based on the PWM duty cycle is the power to be output in the current cycle, which takes into account both the stability of the power grid and the current quality during adjustment.

[0025] Based on a further improvement of the above method, the current setpoint is calculated based on the voltage deviation, specifically by using PID calculation to obtain the current setpoint through the voltage deviation.

[0026] The beneficial effect of the above-mentioned further improvement scheme is that it is possible to obtain the current setpoint based on the voltage deviation.

[0027] Based on a further improvement of the above method, the current deviation is the difference between the current feedback value of the current cycle and the current setpoint value.

[0028] The beneficial effect of the above-mentioned further improvement scheme is that it can obtain the current deviation value.

[0029] A further improvement to the above method, specifically, obtaining the PWM duty cycle based on the current deviation and the current limiting threshold, includes:

[0030] When the current deviation is greater than 0, the PWM duty cycle is reduced until the current deviation is 0, and the corresponding PWM duty cycle is obtained.

[0031] If the current deviation is less than 0, the PWM duty cycle is increased, and it is determined whether the corresponding expected current exceeds the current limiting threshold.

[0032] If so, the current limiting threshold is set to the desired current, and the corresponding PWM duty cycle is obtained.

[0033] Otherwise, increase the PWM duty cycle until the current deviation is 0, and obtain the corresponding PWM duty cycle.

[0034] The beneficial effect of the above-mentioned further improvement scheme is that it can realize the calculation of the inner current loop and obtain a reliable PWM duty cycle.

[0035] On the other hand, embodiments of the present invention provide a power supply network, which is composed of multiple power supply units connected in parallel. Each power supply unit includes a power conversion unit, a power management unit, a power output interface, and a communication bus.

[0036] The power management unit is used to send voltage setpoints to the power conversion unit, and also obtains voltage feedback values ​​reported by other power supply units in the power supply network through the communication bus, and stores voltage feedback setting values ​​for each cycle.

[0037] The power conversion unit reads the voltage feedback values ​​reported by other power supply units in the power supply network and the voltage feedback set value of the previous cycle obtained by the power management unit. It also obtains the current cycle voltage feedback value and current feedback value of the power supply unit itself through the power supply output interface. The power conversion unit includes a voltage feedback calculator, a voltage regulator, a current regulator, and a power conversion unit.

[0038] The voltage feedback calculator calculates the current cycle voltage feedback setpoint based on the current cycle voltage feedback value and the voltage feedback values ​​reported by other power supply units in the power supply network.

[0039] The voltage regulator is used to calculate the current setpoint based on the voltage setpoint and the voltage deviation calculated from the current cycle voltage feedback value.

[0040] The current regulator is used to calculate the PWM duty cycle based on the current deviation calculated from the current setpoint and the current feedback value of the current cycle, and outputs it to the power conversion unit.

[0041] The power conversion unit is used to obtain and output adjusted power based on the duty cycle.

[0042] The beneficial effects of the above technical solution are as follows: It provides a system composition and corresponding functions of each component that can realize parallel networking power supply of multiple power supply units and take into account power supply quality and stability when adjusting output power.

[0043] This invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor executes a communication-based masterless parallel control method for mobile microgrids provided in this invention.

[0044] The beneficial effects of the above technical solution are as follows: the electronic device can be applied to a power grid composed of multiple power supply units and execute the communication-based masterless parallel control method for mobile microgrids provided in the embodiments of the present invention and obtain the corresponding beneficial effects.

[0045] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements a communication-based masterless parallel control method for mobile microgrids provided in this invention.

[0046] The beneficial effects of the above technical solution are as follows: the computer-readable storage medium can be set in a power grid composed of multiple power supply units. When the power grid needs it, it can execute the computer program stored in the computer-readable storage medium to implement the communication-based masterless parallel control method for mobile microgrids provided in this embodiment of the invention and obtain the corresponding beneficial effects.

[0047] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from the description and drawings, which are particularly pointed out. Attached Figure Description

[0048] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0049] Figure 1 This is a flowchart of the method in Embodiment 1 of the present invention.

[0050] Figure 2 This is a schematic diagram of a mobile microgrid structure as exemplified in Embodiment 2 of the present invention.

[0051] Figure 3 This is a schematic diagram of the power conversion unit structure as exemplified in Embodiment 2 of the present invention. Detailed Implementation

[0052] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0053] Example 1:

[0054] A specific embodiment of the present invention discloses a communication-based masterless parallel control method for mobile microgrids, such as... Figure 1 As shown.

[0055] A power supply network is formed by multiple mobile microgrids connected in parallel. Each mobile microgrid generates output power based on its received voltage setpoint and supplies power to the load based on the output power. The mobile microgrids are interconnected via a communication bus, and report voltage feedback values ​​to other mobile microgrids in the power supply network through the communication bus. Each microgrid continuously adjusts its output power by periodically iteratively executing the following process, which specifically includes:

[0056] Read its own voltage deviation threshold and current limit threshold, and sample the current cycle voltage feedback value and current feedback value;

[0057] The current period voltage feedback value is reported through the communication bus, and the voltage feedback values ​​reported by other mobile microgrids in the power supply network in the current period are obtained.

[0058] The current cycle voltage feedback setpoint is calculated based on the current cycle voltage feedback value and the current cycle voltage feedback values ​​reported by other mobile microgrids in the power supply network.

[0059] The voltage deviation is calculated based on the current cycle voltage feedback setpoint and the voltage setpoint.

[0060] Determine whether the absolute value of the voltage deviation is less than the voltage deviation threshold; if so, set the voltage deviation to 0.

[0061] After adjusting the power based on the voltage deviation and outputting it, the next iteration is executed after a one-cycle interval.

[0062] Generally, when a large load output is required, multiple mobile microgrids are connected in parallel to form a power grid to supply power to the load. Each mobile microgrid continuously samples its own output voltage and current to obtain voltage feedback values ​​and current feedback values, and feeds these values ​​back to itself. When the load changes, the voltage and current feedback values ​​will change, and the required output power needs to be adjusted based on these values ​​to maintain load balance. This adjustment is performed continuously and iteratively, which is determined by the structure and operating principle of the mobile microgrid. In the prior art, due to the master-slave structure, the voltage feedback values ​​also need to be reported to the master mobile microgrid. When the master mobile microgrid receives the voltage feedback values ​​reported by each slave mobile microgrid, it calculates the voltage setpoint that the slave needs to adjust and sends it to the corresponding slave. Once the master fails and crashes, the power grid will collapse.

[0063] In this embodiment, as Figure 2 As shown, the multiple mobile microgrids constituting the power supply network adopt a masterless structure, that is, the mobile microgrids are interconnected based on a communication bus and report voltage feedback values ​​to other mobile microgrids in the power supply network through the communication bus. The advantage of this design is that it avoids the power supply network from going down when the master fails due to a problem with the master.

[0064] Therefore, within the power supply network employing a masterless structure, each mobile microgrid continuously adjusts its output power by periodically iteratively executing the following process, which specifically includes:

[0065] Step 1: Read its own voltage deviation threshold and current limit threshold, and sample the current cycle voltage feedback value and current feedback value.

[0066] The self-defined voltage deviation threshold and current limiting threshold are set values ​​for each mobile microgrid. Upon initiating the control adjustment process after receiving the voltage setpoint, each mobile microgrid reads its own voltage deviation threshold and current limiting threshold. For each mobile microgrid receiving the voltage setpoint, the control adjustment process is executed in parallel. The mobile microgrid receiving the voltage setpoint samples the current cycle voltage feedback value and current feedback value. Since the process of each mobile microgrid sampling its own voltage feedback value and current feedback value within the power supply network is continuously executed periodically, within one cycle after initiating the control adjustment process, the self-sampled voltage feedback value and current feedback value of the mobile microgrid receiving the voltage setpoint are used as its current cycle voltage feedback value and current feedback value. Unless otherwise specified, the cycle in this embodiment refers to the cycle duration corresponding to the control frequency.

[0067] Step 2: Report the current period voltage feedback value through the communication bus, and obtain the voltage feedback values ​​reported by other mobile microgrids in the power supply network in the current period.

[0068] In this embodiment, each mobile microgrid within the power supply network periodically reads and obtains its own voltage feedback value, and reports its obtained voltage feedback value to other mobile microgrids outside the power supply network via a communication bus. From the moment the mobile microgrid receives the issued voltage setpoint and initiates the control process, step 2 is executed once per cycle, thus obtaining a voltage feedback value that reflects the real-time voltage output of all mobile microgrids in the power supply network.

[0069] Step 3: Calculate the current cycle voltage feedback setpoint based on the current cycle voltage feedback value and the current cycle voltage feedback values ​​reported by other mobile microgrids in the power supply network.

[0070] Once the current cycle voltage feedback value and the current cycle voltage feedback values ​​reported by other mobile microgrids in the power supply network have been obtained, the current cycle voltage feedback setpoint can be calculated using the average method. Specifically, the average value of the current cycle voltage feedback is calculated based on the current cycle voltage feedback values ​​of all mobile microgrids and used as the current cycle voltage feedback setpoint.

[0071] When the mobile microgrid within the power supply network fails to report the current cycle voltage feedback value, a first-order filtering method is used. Furthermore, the current cycle voltage feedback setpoint is calculated using the following formula, which is specifically expressed as follows:

[0072] In the formula, U b It is the current cycle voltage feedback setpoint, U blast It is the voltage feedback setpoint of the previous cycle, n is the number of mobile microgrids connected in parallel to the power supply network, and U bx It is the voltage feedback value reported by any other mobile microgrid within the power supply network during the current cycle.

[0073] Specifically, based on the voltage feedback setpoint U of the previous cycle blast The average of ×(n-1) and the current cycle voltage feedback value reported by any mobile microgrid is used as the current cycle voltage feedback setpoint. The purpose of this process is to find a value that is closest to the current cycle real-time voltage feedback setpoint, based on the voltage feedback setpoint of the previous cycle combined with any reported voltage feedback setpoint of the current cycle. This is determined by the characteristics of mobile microgrids. The current cycle voltage feedback setpoint calculated based on this value has minimal impact on the power supply quality and stability of the power grid in subsequent calculations.

[0074] The purpose of calculating the current cycle voltage feedback value in step 3 or step 4 is to ensure that the voltage feedback of all mobile microgrids in the same cycle is as consistent as possible before proceeding with subsequent steps, thereby avoiding instability caused by different voltage feedback values ​​of each mobile microgrid.

[0075] Step 5: Calculate the voltage deviation based on the current cycle voltage feedback setting value and the voltage setpoint.

[0076] Specifically, the voltage deviation is the difference between the voltage setpoint and the current cycle voltage feedback setting, reflecting the amount of voltage output change that needs to be adjusted based on the voltage setpoint and the current cycle voltage feedback setting.

[0077] Next, step 6: Determine whether the absolute value of the voltage deviation is less than the voltage deviation threshold. If it is, terminate the process.

[0078] Otherwise, after adjusting the power based on the voltage deviation and outputting it, the next iteration is executed after a one-cycle interval.

[0079] Specifically, the iterative process in this embodiment involves each controller obtaining and outputting adjusted power based on the voltage deviation to achieve regulation, specifically including:

[0080] The current setpoint is calculated based on the voltage deviation.

[0081] The current deviation is obtained based on the given current value and the current feedback value of the current cycle.

[0082] The PWM duty cycle is calculated based on the current deviation.

[0083] The adjusted power is obtained based on the voltage deviation, the current deviation, and the duty cycle.

[0084] Furthermore, the current setpoint is calculated based on the voltage deviation, specifically by using PID calculation to obtain the current setpoint from the voltage deviation.

[0085] Specifically, the current setpoint is obtained by PID calculation based on the voltage deviation, which is the operation of voltage inner loop control. The corresponding current value is calculated based on the set load resistance and the voltage deviation, and then the adjustment amount is calculated by PID to finally obtain the current setpoint.

[0086] The current deviation is then obtained based on the current setpoint and the current feedback value of the current cycle.

[0087] Specifically, the current deviation is the difference between the current feedback value of the current cycle and the current setpoint value.

[0088] Furthermore, the step of obtaining the PWM duty cycle based on the current deviation and the current limiting threshold specifically includes:

[0089] When the current deviation is greater than 0, the PWM duty cycle is reduced until the current deviation is 0, and the corresponding PWM duty cycle is saved.

[0090] If the current deviation is less than 0, the PWM duty cycle is increased, and it is determined whether the corresponding expected current exceeds the current limiting threshold.

[0091] If so, the current limiting threshold is set to the desired current, and the corresponding PWM duty cycle is saved.

[0092] Otherwise, increase the PWM duty cycle until the current deviation is 0, and save the corresponding PWM duty cycle.

[0093] Generally, a mobile microgrid increases or decreases the desired output current by adjusting the PWM duty cycle through an inner current loop. The current deviation is the difference between the current feedback value of the current cycle and the current setpoint, representing the amount of current change to be adjusted. When the current deviation is greater than 0, it means the current feedback value of the current cycle is greater than the current setpoint, and the PWM duty cycle needs to be lowered to reduce the output current. Conversely, when the current feedback value of the current cycle is less than the current setpoint, the PWM duty cycle needs to be increased to increase the desired current. The increase in desired current by increasing the PWM duty cycle cannot exceed the current limiting threshold to ensure that the current change caused by the final output does not exceed the limit. Once the PWM duty cycle is obtained, the regulated power is further generated and output based on the PWM duty cycle. The mobile microgrid, after receiving the given voltage value, outputs regulated power in the current cycle, then after a one-cycle interval, iteratively executes the process again, outputs the next regulated power, and then after another one-cycle interval, repeating this cycle. The one-cycle interval after each iteration is intended to allow the output regulated power a one-cycle stabilization time, further ensuring power supply quality and stability. The cycle duration is determined by the control frequency; for example, when the control frequency is 10kHz, the cycle duration is 100µs.

[0094] After multiple iterations of the control process, the current cycle voltage feedback setpoint will gradually change. During each iteration, it is necessary to determine whether the adjustment is complete based on the voltage deviation threshold read in step 1. Specifically, if the absolute value of the voltage deviation is less than the voltage deviation threshold, it means the adjustment is complete, and the voltage deviation is set to 0. When the voltage deviation is 0, the current deviation is 0, thus maintaining the stable power output of the previous cycle's PWM duty cycle.

[0095] In this embodiment, the process that is periodically and iteratively executed by each mobile microgrid is continuously running. When the load changes or the voltage setpoint of the mobile microgrid in the power supply network changes, the output power can be adjusted by periodically and iteratively executing the process, while ensuring a stable power supply.

[0096] In this embodiment, all mobile microgrids within the power supply network are interconnected via a communication bus. Each mobile microgrid generates output power based on its received voltage setpoint and supplies power to the load based on the output power. It reports voltage feedback values ​​to other mobile microgrids within the power supply network via the communication bus. Each microgrid periodically iterates through an adjustment process: reading its own voltage deviation threshold and current limiting threshold to obtain the current cycle voltage feedback value and current feedback value; reading the current cycle voltage feedback values ​​reported by other mobile microgrids within the power supply network via the communication bus; calculating the current cycle voltage feedback setpoint based on the current cycle voltage feedback value and the voltage setpoint; calculating the voltage deviation based on the current cycle voltage feedback setpoint and the voltage setpoint; and determining whether the absolute value of the voltage deviation is less than the voltage deviation threshold. If it is, the process terminates; otherwise, after obtaining and outputting the adjusted power based on the voltage deviation, the next iteration is executed after a one-cycle interval. Each iteration calculates the voltage feedback setpoint based on the voltage feedback of all mobile microgrids in the power grid during the current period obtained from sampling, and then adjusts and outputs the power. This not only ensures the power quality and stability of the parallel power grid structure, but also, due to the masterless structure, prevents the overall power grid from collapsing even if one of the mobile microgrids fails. This solves the problem of not being able to balance power quality and stability in existing technologies.

[0097] Although not explicitly shown in this embodiment, those skilled in the art should know that mobile microgrids include power supply and energy storage functions by default.

[0098] Example 2:

[0099] A second specific embodiment of the present invention discloses a power supply network, which is composed of multiple power supply units. Each power supply unit includes a power conversion unit, a power management unit, a power output interface, and a communication bus.

[0100] The power management unit is used to send voltage setpoints to the power conversion unit, and also obtains voltage feedback values ​​reported by other power supply units in the power supply network through the communication bus, and stores voltage feedback setting values ​​for each cycle.

[0101] The power conversion unit reads the voltage feedback values ​​reported by other power supply units in the power supply network and the voltage feedback set value of the previous cycle obtained by the power management unit. It also obtains the current cycle voltage feedback value and current feedback value of the power supply unit itself through the power supply output interface. The power conversion unit includes a voltage feedback calculator, a voltage regulator, a current regulator, and a power conversion unit.

[0102] The voltage feedback calculator calculates the current cycle voltage feedback setpoint based on the current cycle voltage feedback value and the voltage feedback values ​​reported by other power supply units in the power supply network.

[0103] The voltage regulator is used to calculate the current setpoint based on the voltage setpoint and the voltage deviation calculated from the current cycle voltage feedback value.

[0104] The current regulator is used to calculate the PWM duty cycle based on the current deviation calculated from the current setpoint and the current feedback value of the current cycle, and outputs it to the power conversion unit.

[0105] The power conversion unit is used to obtain and output adjusted power based on the duty cycle.

[0106] Optionally, the power supply unit can be a mobile microgrid, UPS, inverter, etc.

[0107] Optionally, the communication bus can be CAN communication, RS485 communication, Ethernet communication, etc.

[0108] For example, Figure 2 The diagram illustrates the overall structure of a mobile microgrid that can constitute the power supply network disclosed in this embodiment, including a power management unit, a power conversion unit, a communication bus, and a power output interface. The power output interface includes a DC bus and an AC bus, wherein the AC bus is connected to AC loads for power supply.

[0109] The power management unit is connected to the communication bus and the power conversion unit. It receives voltage feedback values ​​reported by other mobile microgrids in the power supply network through the communication bus and also stores the voltage feedback setting values ​​for each cycle.

[0110] The power conversion unit obtains the current cycle voltage feedback value and current feedback value of the mobile microgrid itself through the AC bus, and also reads the voltage feedback value and the previous cycle voltage feedback setting value reported by other mobile microgrids in the power supply network obtained by the power management unit.

[0111] Figure 3 The composition of the power conversion unit is further illustrated, specifically including: a voltage feedback calculator, a voltage regulator, a current regulator, and a power conversion unit, wherein...

[0112] The voltage feedback calculator calculates the current cycle voltage feedback setpoint based on the current cycle voltage feedback value and the voltage feedback values ​​reported by other mobile microgrids in the power supply network. Figure 3 Although the communication bus is directly connected to the voltage feedback calculator, this is only to indicate that the voltage feedback values ​​reported by other mobile microgrids in the power supply network are transmitted through the communication bus, and is not intended to illustrate the actual connection structure. In practice, the voltage feedback calculator obtains the voltage feedback values ​​reported by other mobile microgrids in the power supply network through the power management unit and calculates the current cycle voltage feedback setting value and the previous cycle voltage feedback setting value.

[0113] The voltage regulator is used to calculate the current setpoint based on the voltage deviation calculated from the voltage setpoint and the current cycle voltage feedback value. The voltage setpoint and the current cycle voltage feedback value are calculated by the power conversion unit to obtain the voltage deviation, and then input to the voltage regulator to complete the voltage inner loop control.

[0114] The current regulator is used to calculate the current deviation based on the current setpoint and the current feedback value of the current cycle, and to calculate the PWM duty cycle based on the current deviation and output it to the power conversion unit. The current setpoint and the current feedback value of the current cycle are used by the power conversion unit to calculate the current deviation and then input to the current regulator to obtain the PWM duty cycle, thereby completing the inner loop current control.

[0115] The power conversion unit is used to obtain and output adjusted power based on the duty cycle.

[0116] Figure 2 The diagram also shows the default energy supply and energy storage components of a mobile microgrid, such as an energy storage system and a distributed power system. The power management unit is connected to the energy storage system, and the power conversion unit is connected to the energy storage system and the distributed power system via the DC bus.

[0117] Furthermore, in the example, in the power supply network formed by parallel mobile microgrids, all mobile microgrids have no master-slave relationship and are interconnected through the communication bus. When the power management unit of a mobile microgrid in the power supply network issues a voltage setpoint, it calculates the current cycle voltage feedback setpoint through its own voltage feedback calculator. The current cycle voltage feedback setpoint then passes through the voltage inner loop, the current inner loop, and the power conversion unit in sequence to output the adjusted power, thereby realizing a masterless, simple, and efficient power supply network.

[0118] Example 3

[0119] A third specific embodiment of the present invention discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes a communication-based masterless parallel control method for mobile microgrids disclosed in Embodiment 1.

[0120] Example 4

[0121] A fourth specific embodiment of the present invention discloses a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements a communication-based masterless parallel control method for mobile microgrids disclosed in Embodiment 1.

[0122] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0123] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A communication-based masterless parallel control method for mobile microgrids, characterized in that, A power supply network is formed by multiple mobile microgrids connected in parallel. Each mobile microgrid generates output power based on its received voltage setpoint and supplies power to the load based on the output power. The mobile microgrids are interconnected via a communication bus, and report voltage feedback values ​​to other mobile microgrids in the power supply network through the communication bus. Each microgrid continuously adjusts its output power by periodically iteratively executing the following process, which specifically includes: Read its own voltage deviation threshold and current limit threshold, and sample the current cycle voltage feedback value and current feedback value; The current period voltage feedback value is reported through the communication bus, and the voltage feedback values ​​reported by other mobile microgrids in the power supply network in the current period are obtained. The current cycle voltage feedback setpoint is calculated based on the current cycle voltage feedback value and the current cycle voltage feedback values ​​reported by other mobile microgrids in the power supply network. The voltage deviation is calculated based on the current cycle voltage feedback setpoint and the voltage setpoint. Determine whether the absolute value of the voltage deviation is less than the voltage deviation threshold; if so, set the voltage deviation to 0. After adjusting the power based on the voltage deviation and outputting it, the next iteration is executed after a one-cycle interval.

2. The communication-based masterless parallel control method for mobile microgrids according to claim 1, characterized in that, The calculation of the current cycle voltage feedback setpoint based on the current cycle voltage feedback value and the current cycle voltage feedback values ​​reported by other mobile microgrids in the power supply network specifically refers to calculating the average current cycle voltage feedback value based on the current cycle voltage feedback values ​​of all mobile microgrids as the current cycle voltage feedback setpoint.

3. The communication-based masterless parallel control method for mobile microgrids according to claim 2, characterized in that, When the mobile microgrid within the power supply network fails to report the current cycle voltage feedback value, the current cycle voltage feedback setpoint is calculated using the following formula, which is specifically expressed as follows: In the formula, U b It is the current cycle voltage feedback setpoint, U blast It is the voltage feedback setpoint of the previous cycle, n is the number of mobile microgrids connected in parallel to the power supply network, and U bx It is the voltage feedback value reported by any other mobile microgrid within the power supply network during the current cycle.

4. The communication-based masterless parallel control method for mobile microgrids according to claim 3, characterized in that, The process of obtaining the adjusted power based on the voltage deviation specifically includes: The current setpoint is calculated based on the voltage deviation. The current deviation is obtained based on the given current value and the current feedback value of the current cycle. The PWM duty cycle is calculated based on the current deviation. The adjusted power is obtained based on the PWM duty cycle.

5. The communication-based masterless parallel control method for mobile microgrids according to claim 4, characterized in that, The current setpoint is calculated based on the voltage deviation, specifically by using PID calculation based on the voltage deviation.

6. The communication-based masterless parallel control method for mobile microgrids according to claim 5, characterized in that, The current deviation is the difference between the current feedback value of the current cycle and the current setpoint value.

7. A communication-based masterless parallel control method for mobile microgrids according to claim 6, characterized in that, The process of obtaining the PWM duty cycle based on the current deviation and the current limiting threshold specifically includes: When the current deviation is greater than 0, the PWM duty cycle is reduced until the current deviation is 0, and the corresponding PWM duty cycle is obtained. If the current deviation is less than 0, the PWM duty cycle is increased, and it is determined whether the corresponding expected current exceeds the current limiting threshold. If so, the current limiting threshold is set to the desired current, and the corresponding PWM duty cycle is obtained. Otherwise, increase the PWM duty cycle until the current deviation is 0, and obtain the corresponding PWM duty cycle.

8. A power supply network, wherein the power supply network is composed of multiple power supply units connected in parallel, characterized in that, Each of the power supply units includes a power conversion unit, a power management unit, a power output interface, and a communication bus, wherein... The power management unit is used to send voltage setpoints to the power conversion unit, and also obtains voltage feedback values ​​reported by other power supply units in the power supply network through the communication bus, and stores voltage feedback setting values ​​for each cycle. The power conversion unit reads the voltage feedback values ​​reported by other power supply units in the power supply network and the voltage feedback set value of the previous cycle obtained by the power management unit. It also obtains the current cycle voltage feedback value and current feedback value of the power supply unit itself through the power supply output interface. The power conversion unit includes a voltage feedback calculator, a voltage regulator, a current regulator, and a power conversion unit. The voltage feedback calculator calculates the current cycle voltage feedback setpoint based on the current cycle voltage feedback value and the voltage feedback values ​​reported by other power supply units in the power supply network. The voltage regulator is used to calculate the current setpoint based on the voltage setpoint and the voltage deviation calculated from the current cycle voltage feedback value. The current regulator is used to calculate the PWM duty cycle based on the current deviation calculated from the current setpoint and the current feedback value of the current cycle, and outputs it to the power conversion unit. The power conversion unit is used to obtain and output adjusted power based on the duty cycle.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor executes the communication-based masterless parallel control method for mobile microgrids as described in claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements a communication-based masterless parallel control method for mobile microgrids as described in any one of claims 1-7.

Images