Power self-adaptive distribution method and system based on residual capacity of ports

Abstract

The invention discloses a port residual capacity-based power adaptive distribution method and system. The power adaptive distribution method comprises the following steps of: calculating the real-time power of a diesel generator port and the real-time power of an inverter port; calculating the residual capacity of the port of the diesel generator according to the real-time power of the port of the diesel generator and the rated power of the diesel generator; calculating a power matching coefficient according to the real-time power of the inverter port and the rated capacity of the inverter; dynamically generating an active power instruction of the inverter by adopting a self-adaptive adjustment algorithm according to the residual capacity of the port of the diesel generator, the power matching coefficient and a manually set lower limit threshold value of the operation interval of the diesel generator; and then changing the output power of the inverter according to the work power instruction so as to indirectly adjust the output power of the diesel generator, so that the output power of the diesel generator is maintained in a set operation interval. Power distribution can be accurately planned according to load characteristics, it is ensured that the diesel generator operates in a high-efficiency interval, and the economical efficiency and reliability of the system are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of power supply system control technology, and in particular to a power adaptive allocation method and system based on port remaining capacity. Background Technology

[0002] With the rapid development of microgrids with high renewable energy penetration, parallel power supply systems using diesel generators and inverters have become widely used. In these systems, the diesel generator provides stable base power support, while the inverter offers rapid power response to smooth power fluctuations. Simultaneously, power distribution is flexibly adjusted through control methods to achieve energy management of the parallel power supply system. However, existing power distribution methods suffer from the following technical problems: Traditional fixed droop factor allocation methods cause diesel generators to operate in an inefficient range (typically below 30% of rated capacity) under light system loads, significantly reducing power generation efficiency and increasing mechanical wear, thus affecting equipment lifespan. Furthermore, as "grey box" devices, the actual droop factor of diesel generators is uncertain, resulting in poor power allocation accuracy and hindering precise power planning. Therefore, in power supply scenarios with random and fluctuating loads, the economic efficiency and long-term reliability of diesel-reverse parallel power supply systems are difficult to guarantee. The simulated port output power curves obtained using the traditional fixed droop factor allocation method are shown below. Figure 4 As shown. Summary of the Invention

[0003] This invention provides a power adaptive allocation method and system based on port remaining capacity to solve the technical problems mentioned in the background art.

[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows: This invention provides a power adaptive allocation method based on port remaining capacity, comprising the following steps: S1. Calculate the real-time power at the diesel generator port. Real-time power at inverter port The diesel generator is connected in parallel with the inverter. S2, Based on the real-time power of the diesel generator port And combined with the rated power of the diesel generator Calculate the remaining capacity of the diesel generator port ; S3, Based on real-time power at the inverter port and inverter rated capacity Calculate the power matching coefficient ; S4. Based on the remaining capacity of the diesel generator port Power matching coefficient Manually set lower limit threshold for diesel generator operating range An adaptive adjustment algorithm is used to dynamically generate the inverter's active power command. Then, based on the power output command... Adjusting the inverter's output power indirectly adjusts the diesel generator's output power, keeping it within a set operating range.

[0005] Furthermore, the step S4 is followed by the following steps: S5. Determine if the inverter's active power command has been reached. The update cycle is set; if so, return to S1; otherwise, maintain the current inverter active power command. .

[0006] Furthermore, step S1 specifically includes the following steps: S11. Use the port power calculation module to collect the real-time voltage of the diesel generator port. Real-time current and the real-time voltage at the inverter port Real-time current ; S12. Based on the real-time voltage at the diesel generator port. Real-time current Calculate the instantaneous power of the diesel generator before port filtering. Then, a first-order inertial low-pass filter algorithm is used to filter the instantaneous power at the diesel generator port before filtering. Smoothing is performed to obtain the real-time power at the diesel generator port. ; S13. Based on the real-time voltage of the inverter port Real-time current Calculate the instantaneous power before inverter port filtering Then, a first-order inertial low-pass filter algorithm is used to filter the instantaneous power at the inverter port. Smoothing is performed to obtain the real-time power at the inverter port. .

[0007] Furthermore, the instantaneous power before filtering at the diesel generator port in S12 The formula for calculation is: ; in, , , These represent the three-phase voltages at the diesel generator terminals, respectively. , , The real-time voltage at the diesel generator port constitutes ; , , These represent the three-phase currents at the diesel generator terminals, respectively. , , The real-time current at the diesel generator port constitutes .

[0008] Furthermore, the instantaneous power before inverter port filtering in S13 The formula for calculation is: ; in, , , These represent the three-phase voltages of the inverter, respectively. , , The real-time voltage of the inverter ; , , These represent the three-phase current of the inverter, respectively. , , The real-time current of the inverter .

[0009] Furthermore, the remaining capacity of the diesel generator port in S2 The formula for calculation is: .

[0010] Furthermore, the power matching coefficient in S3 The formula for calculation is: .

[0011] Furthermore, the adaptive adjustment algorithm is expressed by the following formula: .

[0012] Furthermore, the set operating range is the high-efficiency operating range; whereby the high-efficiency operating range refers to the rated power of the diesel generator. The range is between 25% and 95%.

[0013] In another aspect, the present invention provides a power adaptive allocation system based on port remaining capacity, configured to or executing the above-described power adaptive allocation method, the power adaptive allocation system comprising: A diesel-inverter parallel power supply system, comprising a diesel generator and an inverter connected in parallel with the diesel generator; The port power calculation module is electrically connected to the diesel generator port and the inverter port, and is used to collect the real-time voltage of the diesel generator port. Real-time current and the real-time voltage at the inverter port Real-time current Then calculate the real-time power at the diesel generator port. Real-time power at inverter port ; The remaining capacity calculation module is used to calculate the real-time power of the diesel generator port. And combined with the rated power of the diesel generator Calculate the remaining capacity of the diesel generator port ; The power matching coefficient calculation module is used to calculate the real-time power of the inverter ports. and inverter rated capacity Calculate the power matching coefficient ; The power command adaptive adjustment module is used to adjust the power command based on the remaining capacity of the diesel generator port. Power matching coefficient Manually set lower limit threshold for diesel generator operating range An adaptive adjustment algorithm is used to dynamically generate the inverter's active power command. Then, based on the power output command... Adjusting the inverter's output power indirectly adjusts the diesel generator's output power, keeping it within a set operating range.

[0014] The beneficial effects of this invention are: 1. This invention discloses a power adaptive allocation method based on port remaining capacity, which introduces the remaining capacity of diesel generator ports. and power matching coefficient This paper describes the allocable power potential of a diesel-reverse parallel power supply system and proposes an adaptive adjustment algorithm based on real-time operating data. This algorithm enables power allocation to be automatically optimized according to the system state, ensuring the power generation efficiency of the diesel generator and avoiding mechanical wear in the inefficient range. It effectively solves the problem that traditional allocation methods cannot balance economy and reliability.

[0015] Furthermore, the power adaptive allocation method provided by this invention can quickly adjust the power allocation ratio through an adaptive adjustment algorithm when the load changes abruptly or the distributed energy power fluctuates, which significantly enhances the anti-disturbance capability and operational stability of the diesel-reverse parallel power supply system. At the same time, this invention improves the operational economy of the diesel-reverse parallel power supply system and avoids the diesel generator from operating in the inefficient range, thereby improving the mechanical life of the diesel generator. Attached Figure Description

[0016] Figure 1 This is a control block diagram of the power adaptive allocation method in this invention; Figure 2 This is a flowchart of the power adaptive allocation method in this invention; Figure 3 This is a schematic diagram of the port output power curves under different power allocation methods in an embodiment of the present invention; Figure 4 The simulation curve of port output power obtained by using the traditional fixed droop coefficient allocation method; Figure 5 The image shows a simulated output power curve of the port obtained using the power adaptive allocation method of this invention. Detailed Implementation

[0017] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many other different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0018] Reference Figure 1 and Figure 2 This application provides a power adaptive allocation method based on port remaining capacity, including the following steps: S1. First, initialize the power adaptive distribution system, and then calculate the real-time power at the diesel generator port. Real-time power at inverter port The diesel generator is connected in parallel with the inverter. S2, Based on the real-time power of the diesel generator port And combined with the rated power of the diesel generator Calculate the remaining capacity of the diesel generator port ; S3, Based on real-time power at the inverter port and inverter rated capacity Calculate the power matching coefficient ; S4. Based on the remaining capacity of the diesel generator port Power matching coefficient Manually set lower limit threshold for diesel generator operating range An adaptive adjustment algorithm is used to dynamically generate the inverter's active power command. Then, based on the power output command... Adjusting the inverter's output power indirectly regulates the diesel generator's output power, keeping it within its high-efficiency operating range, where the high-efficiency operating range refers to the diesel generator's rated power. The range is between 25% and 95%.

[0019] This invention introduces the remaining capacity of the diesel generator port. and power matching coefficient This paper describes the allocable power potential of a diesel-reverse parallel power supply system and proposes an adaptive adjustment algorithm based on real-time operating data. This algorithm enables power allocation to be automatically optimized according to the system state, ensuring the power generation efficiency of the diesel generator and avoiding mechanical wear in the inefficient range. It effectively solves the problem that traditional allocation methods cannot balance economy and reliability.

[0020] Furthermore, the power adaptive allocation method provided by this invention can quickly adjust the power allocation ratio through an adaptive adjustment algorithm when the load changes abruptly or the distributed energy power fluctuates, which significantly enhances the anti-disturbance capability and operational stability of the diesel-reverse parallel power supply system. At the same time, this invention improves the operational economy of the diesel-reverse parallel power supply system and avoids the diesel generator from operating in the inefficient range, thereby improving the mechanical life of the diesel generator.

[0021] In some embodiments, after step S4, the following steps are further included: S5, Inverter active power command The update cycle is input into the inverter controller to determine whether the inverter active power command has been reached. The update cycle is set; if so, return to S1; otherwise, maintain the current inverter active power command. .

[0022] In some embodiments, S1 specifically includes the following steps: S11. First, initialize the power adaptive distribution system by configuring the initial preset parameters for the power adaptive distribution system, including the rated power of the diesel generator. Lower threshold of diesel generator's high-efficiency operating range Inverter rated capacity and inverter active power command The update cycle; Real-time voltage at the diesel generator port is collected using a port power calculation module. Real-time current and the real-time voltage at the inverter port Real-time current ; S12. Based on the real-time voltage at the diesel generator port. Real-time current Calculate the instantaneous power of the diesel generator before port filtering. Then, a first-order inertial low-pass filter algorithm is used to filter the instantaneous power at the diesel generator port before filtering. Smoothing is performed to eliminate high-frequency noise, and the real-time power at the diesel generator port is obtained. ; S13. Based on the real-time voltage of the inverter port Real-time current Calculate the instantaneous power before inverter port filtering Then, a first-order inertial low-pass filter algorithm is used to filter the instantaneous power at the inverter port. Smoothing is performed to eliminate high-frequency noise and obtain the real-time power at the inverter port. .

[0023] In some embodiments, the instantaneous power before filtering at the diesel generator port in S12 The formula for calculation is: ; in, , , These represent the three-phase voltages at the diesel generator terminals, respectively. , , The real-time voltage at the diesel generator port constitutes ; , , These represent the three-phase currents at the diesel generator terminals, respectively. , , The real-time current at the diesel generator port constitutes .

[0024] In some embodiments, the instantaneous power before inverter port filtering in S13 The formula for calculation is: ; in, , , These represent the three-phase voltages of the inverter, respectively. , , The real-time voltage of the inverter ; , , These represent the three-phase current of the inverter, respectively. , , The real-time current of the inverter .

[0025] In some embodiments, the remaining capacity of the diesel generator port in S2 The formula for calculation is: .

[0026] In some embodiments, the power matching coefficient in S3 The formula for calculation is: .

[0027] In some embodiments, the adaptive adjustment algorithm is expressed by the following formula: .

[0028] Among them, the lower limit threshold of the high-efficiency operating range of diesel generators The setting depends on the actual situation and is usually set to the rated power of the diesel generator. 25%~35%. Inverter active power command. The positive and negative signs correspond to the power flow direction of the inverter.

[0029] In some embodiments, S4 specifically includes the following steps: S41. Based on the remaining capacity of the diesel generator port Power matching coefficient Lower threshold of diesel generator's high-efficiency operating range An adaptive adjustment algorithm is used to dynamically generate the inverter's active power command. ; S42, then according to the power command Adjusting the inverter's output power keeps the diesel generator's output power within its efficient operating range.

[0030] The effectiveness of this invention is verified through simulation experiments. See below. Figure 3 As shown in the figure, this diagram illustrates the simulation results of other methods compared to the present invention. The simulation results of the present invention are shown in [the figure below]. Figure 3As shown in the proposed method, the simulation results of this invention are all within the yellow area, thus ensuring the efficiency of the diesel generator. In contrast, other methods all pass through the yellow area.

[0031] Figure 4 The output power simulation curve is obtained using the traditional fixed droop coefficient allocation method. Figure 5 This is a simulated curve of the port output power obtained using the power adaptive allocation method in this invention. Figure 4 and Figure 5 The correctness of this invention has been verified.

[0032] In another aspect, the present invention provides a power adaptive allocation system based on port remaining capacity, configured to or executing the above-described power adaptive allocation method, the power adaptive allocation system comprising: The diesel-inverter parallel power supply system includes a diesel generator and an inverter connected in parallel with the diesel generator; the inverter is controlled by a virtual synchronous generator (VSG) and has bidirectional energy flow capability; The port power calculation module is electrically connected to the diesel generator port and the inverter port, and is used to collect the real-time voltage of the diesel generator port. Real-time current and the real-time voltage at the inverter port Real-time current Then calculate the real-time power at the diesel generator port. Real-time power at inverter port ; The remaining capacity calculation module is used to calculate the real-time power of the diesel generator port. And combined with the rated power of the diesel generator Calculate the remaining capacity of the diesel generator port ; The power matching coefficient calculation module is used to calculate the real-time power of the inverter ports. and inverter rated capacity Calculate the power matching coefficient ; The power command adaptive adjustment module is used to adjust the power command based on the remaining capacity of the diesel generator port. Power matching coefficient Manually set lower limit threshold for diesel generator operating range An adaptive adjustment algorithm is used to dynamically generate the inverter's active power command. Then, based on the power output command... Adjusting the inverter's output power indirectly adjusts the diesel generator's output power, keeping it within its efficient operating range.

[0033] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A power adaptive allocation method based on port remaining capacity, characterized in that, Includes the following steps: S1. Calculate the real-time power at the diesel generator port. Real-time power at inverter port The diesel generator is connected in parallel with the inverter. S2, Based on the real-time power of the diesel generator port And combined with the rated power of the diesel generator Calculate the remaining capacity of the diesel generator port ; S3, Based on real-time power at the inverter port and inverter rated capacity Calculate the power matching coefficient ; S4. Based on the remaining capacity of the diesel generator port Power matching coefficient Manually set lower limit threshold for diesel generator operating range An adaptive adjustment algorithm is used to dynamically generate the inverter's active power command. Then, based on the power output command... Adjusting the inverter's output power indirectly adjusts the diesel generator's output power, keeping it within a set operating range.

2. The power adaptive allocation method based on port remaining capacity according to claim 1, characterized in that, The following steps are included after step S4: S5. Determine if the inverter's active power command has been reached. The update cycle is set; if so, return to S1; otherwise, maintain the current inverter active power command. .

3. The power adaptive allocation method based on port remaining capacity according to claim 1, characterized in that, S1 specifically includes the following steps: S11. Use the port power calculation module to collect the real-time voltage of the diesel generator port. Real-time current and the real-time voltage at the inverter port Real-time current ; S12. Based on the real-time voltage at the diesel generator port. Real-time current Calculate the instantaneous power of the diesel generator before port filtering. Then, a first-order inertial low-pass filter algorithm is used to filter the instantaneous power at the diesel generator port before filtering. Smoothing is performed to obtain the real-time power at the diesel generator port. ; S13. Based on the real-time voltage of the inverter port Real-time current Calculate the instantaneous power before inverter port filtering Then, a first-order inertial low-pass filter algorithm is used to filter the instantaneous power at the inverter port. Smoothing is performed to obtain the real-time power at the inverter port. .

4. The power adaptive allocation method based on port remaining capacity according to claim 3, characterized in that, The instantaneous power of the diesel generator port before filtering in S12 The formula for calculation is: ； in, , , These represent the three-phase voltages at the diesel generator terminals, respectively. , , The real-time voltage at the diesel generator port constitutes ; , , These represent the three-phase currents at the diesel generator terminals, respectively. , , The real-time current at the diesel generator port constitutes .

5. The power adaptive allocation method based on port remaining capacity according to claim 3, characterized in that, The instantaneous power before filtering at the inverter port in S13 The formula for calculation is: ； in, , , These represent the three-phase voltages of the inverter, respectively. , , The real-time voltage of the inverter ; , , These represent the three-phase current of the inverter, respectively. , , The real-time current of the inverter .

6. The power adaptive allocation method based on port remaining capacity according to claim 1, characterized in that, The remaining capacity of the diesel generator port in S2 The formula for calculation is: 。 7. The power adaptive allocation method based on port remaining capacity according to claim 1, characterized in that, The power matching coefficient in S3 The formula for calculation is: 。 8. The power adaptive allocation method based on port remaining capacity according to claim 1, characterized in that, The adaptive adjustment algorithm is expressed by the following formula: 。 9. The power adaptive allocation method based on port remaining capacity according to claim 1, characterized in that, The set operating range is the high-efficiency operating range; where the high-efficiency operating range refers to the rated power of the diesel generator. The range is between 25% and 95%.

10. A power adaptive allocation system based on port remaining capacity, characterized in that, The power adaptive allocation system is configured to perform the power adaptive allocation method according to any one of claims 1 to 9, and includes: A diesel-inverter parallel power supply system, comprising a diesel generator and an inverter connected in parallel with the diesel generator; The port power calculation module is electrically connected to the diesel generator port and the inverter port, and is used to collect the real-time voltage of the diesel generator port. Real-time current and the real-time voltage at the inverter port Real-time current Then calculate the real-time power at the diesel generator port. Real-time power at inverter port ; The remaining capacity calculation module is used to calculate the real-time power of the diesel generator port. And combined with the rated power of the diesel generator Calculate the remaining capacity of the diesel generator port ; The power matching coefficient calculation module is used to calculate the real-time power of the inverter ports. and inverter rated capacity Calculate the power matching coefficient ; The power command adaptive adjustment module is used to adjust the power command based on the remaining capacity of the diesel generator port. Power matching coefficient Manually set lower limit threshold for diesel generator operating range An adaptive adjustment algorithm is used to dynamically generate the inverter's active power command. Then, based on the power output command... Adjusting the inverter's output power indirectly adjusts the diesel generator's output power, keeping it within a set operating range.

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