Diesel storage intelligent micro-grid system

Abstract

The invention discloses a diesel-storage intelligent micro-grid system. A diesel generator charges an energy storage unit or cooperatively supplies power when power supply is insufficient; the battery energy storage unit stores electric energy and supplies power to a load; the micro-grid energy management system dynamically coordinates the output proportion, and a harmonic suppression module suppresses harmonic interference; the load prediction module predicts load power change; the transient response control module deals with transient power impact; the power distribution system is connected to a main power supply and is switched to a diesel generator power supply mode when power supply of the main power supply does not meet requirements; when the diesel generator supplies power, the bidirectional converter converts electric energy into charging current of the energy storage unit and inhibits harmonic interference; when the energy storage unit supplies power, the direct current is converted into the alternating current required by the load. According to the invention, seamless switching of multiple energy sources, active stabilization of power fluctuation, flexible conversion of electric energy forms, optimization of energy distribution efficiency and comprehensive improvement of the survivability of the micro-grid can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of energy storage technology optimization, and particularly relates to a diesel storage intelligent microgrid system. BACKGROUND

[0002] Microgrid systems often rely on diesel generators as backup power sources, but their operation has significant defects: harmonic interference seriously pollutes the power grid, dynamic response is slow and difficult to respond to load mutations, fuel efficiency is low and maintenance is frequent. When renewable energy such as wind power and photovoltaic power is used as the main power source, natural volatility is easy to cause power supply interruption; and the impact load in the industrial scene will cause voltage flicker and even system collapse. In the prior art, the diesel generator and the energy storage unit lack real-time optimization capability, the multi-energy switching has the risk of power supply interruption, and the harmonic suppression and transient response modules often run independently, which cannot guarantee the power supply quality and continuity of critical loads, and need to be solved. SUMMARY

[0003] To solve the technical problems in the background art, the present application provides a diesel storage intelligent microgrid system, comprising:

[0004] A diesel generator, as a backup power source, is connected to a battery energy storage unit through a bidirectional converter, used to charge the energy storage unit or to cooperate with power supply when power supply is insufficient;

[0005] A battery energy storage unit is connected to a load through a bidirectional converter, used to store electrical energy and supply power to the load;

[0006] A microgrid energy management system is used to dynamically coordinate the output proportion of the diesel generator and the energy storage unit,

[0007] The microgrid energy management system integrates:

[0008] A harmonic suppression module is used to suppress the harmonic interference generated by the diesel generator;

[0009] A load prediction module is used to predict the load power change trend;

[0010] A transient response control module is used to respond to the transient power impact of the load;

[0011] A power distribution system is configured with a multi-source input switching interface, used to access city power, wind power or photovoltaic power as the main power source, and switch to diesel generator power supply mode when the main power supply does not meet the requirements;

[0012] The bidirectional converter can realize the following functions:

[0013] When the diesel generator supplies power, the electrical energy is converted into a charging current for the energy storage unit, and the harmonic interference is suppressed;

[0014] When the energy storage unit is powered, direct current is converted into alternating current required by the load, and the power demand of the load is dynamically adapted.

[0015] Further, the harmonic suppression module comprises: a harmonic analysis unit that monitors the harmonic components of the diesel generator and the load in real time; a reverse harmonic injection unit that generates a reverse signal with the same amplitude and opposite phase as the harmonic component through a bidirectional converter to offset the harmonic interference of the diesel generator; the harmonic suppression module is activated in the following scenarios: when the diesel generator is powered alone; when the diesel generator and the energy storage unit are cooperatively powered and the harmonic distortion rate is detected to exceed the preset threshold.

[0016] Further, the load prediction module comprises: an AI algorithm unit that predicts the load power change trend in the future period based on historical load data, real-time working condition data and environmental parameters; an energy storage pre-scheduling unit that generates the charging and discharging strategy of the energy storage unit according to the prediction result, and increases the state of charge of the energy storage unit before the load power rises, or reduces the charging power before the load power drops; the load prediction module is activated in the following scenarios: when the system accesses the main power supply of city power / wind and light power, for optimizing the scheduling of the energy storage unit; when the load type is detected to be a nonlinear or impact device, for predicting the instantaneous power demand.

[0017] Further, the transient response control module comprises: an impact load detection unit that identifies the trigger of the impact load by collecting the current change rate and device control signal at the load end in real time; a super-fast charging and discharging unit that increases the output power of the energy storage unit to a preset excess power greater than the rated power during the action of the impact load, and limits the duration to prevent overload; the transient response control module is activated in the following scenarios: when the instantaneous power change rate is detected to exceed the preset threshold; when the device emergency stop or high energy release instruction is received.

[0018] Further, the harmonic suppression module, the load prediction module and the transient response control module are cooperatively controlled through the micro-grid energy management system, specifically including: when the load prediction module predicts that the impact load is about to start, the transient response control module is activated in standby state in advance, and the harmonic suppression module is started synchronously to offset the harmonic distortion possibly caused by the diesel generator and the load; when the main power supply of city power / wind and light power is switched to the diesel generator power supply, the load prediction module and the harmonic suppression module are linked to dynamically adjust the output proportion of the energy storage unit to suppress voltage fluctuation.

[0019] Further, the cooperative work of the harmonic suppression module and the transient response control module includes: during the action of the impact load, while the transient response control module improves the output power of the energy storage unit, the harmonic suppression module suppresses the harmonic components caused by the power mutation in real time, ensuring the stability of the voltage and frequency at the load end; when the diesel generator causes output distortion due to load mutation, the harmonic suppression module and the energy storage unit cooperatively compensate the reactive power, reducing the harmonic emission of the diesel generator.

[0020] Further, the cooperative work of the load prediction module and the transient response control module includes: the load prediction module predicts the trigger time point of the impact load according to the AI algorithm, and sends a preloading instruction to the transient response control module in advance, so that the SOC (or more accurately, the output power capability) of the energy storage unit is improved to a preset threshold; after the impact load ends, the load prediction module optimizes the power recovery rate of the transient response control module in combination with historical data, avoiding secondary power impact.

[0021] Further, the micro-grid energy management system further includes: a dynamic priority allocation unit, which marks key loads and non-key loads according to load types; when the system power supply capacity is insufficient, the non-key loads are preferentially cut off, and through the cooperative control of the harmonic suppression module, the load prediction module and the transient response control module, the power supply quality and continuity of the key loads are guaranteed.

[0022] The present application realizes multiple technical breakthroughs through intelligent cooperation of diesel generators and battery energy storage units and integrated control of micro-grid energy management systems. Firstly, the harmonic suppression module analyzes the harmonic spectrum of the diesel generator and the load in real time, and precisely cancels the interference by injecting reverse harmonic signals through the bidirectional converter, eliminating voltage waveform distortion and protecting precision equipment from harmonic damage. Secondly, the load prediction module predicts future load trends based on artificial intelligence algorithms that integrate historical data and environmental parameters, and adjusts the charging and discharging strategy of the energy storage unit in advance to improve the state of charge before the load rises and reduce the charging power before the load drops, significantly reducing the number of diesel generator start-stop cycles to extend its life. Thirdly, the transient response control module detects load current mutations or equipment emergency stop signals within milliseconds, instantly increases the energy storage output to an excess power mode, strictly limits the time to support impact loads, prevents diesel generator overload and shutdown, and ensures continuous operation of critical equipment. Fourthly, the three core modules work together: the load prediction module predicts impact loads and wakes up the transient response standby, simultaneously activates the harmonic suppression module; the main power supply is switched to adjust the energy storage output to smooth voltage fluctuations; the harmonic suppression and transient response modules work together to cancel harmonics and power surges during impact loads; after the load is completed, the power is intelligently optimized to avoid secondary impact. Fifthly, the dynamic priority allocation unit marks critical loads and automatically cuts off non-critical loads when power is insufficient, and the three modules work together to ensure the purity of critical load voltage and uninterrupted power supply. Finally, it realizes seamless switching of multiple energy sources, active power fluctuation suppression, flexible conversion of energy forms, optimization of energy distribution efficiency, and overall improvement of micro-grid survival ability. DETAILED DESCRIPTION

[0023] The diesel storage intelligent micro-grid system proposed by the present application comprises: a diesel generator, a battery energy storage unit, a micro-grid energy management system, a bidirectional converter, and a power distribution system. The diesel generator serves as a backup power supply. The diesel generator is connected to the battery energy storage unit through the bidirectional converter and is used to charge the energy storage unit or provide power in conjunction with the battery energy storage unit when the power supply is insufficient. The battery energy storage unit is connected to the load through the bidirectional converter and is used to store and supply power to the load. The micro-grid energy management system dynamically coordinates the output ratio of the diesel generator and the energy storage unit. The micro-grid energy management system integrates a harmonic suppression module, a load prediction module, and a transient response control module. The harmonic suppression module is used to suppress harmonic interference generated by the diesel generator. The load prediction module is used to predict the trend of load power changes. The transient response control module is used to respond to transient power surges of the load. The power distribution system is configured with a multi-source input switching interface. The power distribution system is used to connect to the mains, wind power, or solar power as the main power supply. When the main power supply does not meet the requirements, the power distribution system switches to the diesel generator power supply mode. The bidirectional converter can perform the following functions: when the diesel generator supplies power, it converts the power into a charging current for the energy storage unit and suppresses harmonic interference; when the energy storage unit supplies power, it converts direct current into alternating current required by the load and dynamically adapts to the load power demand.

[0024] The diesel generator is connected to the battery energy storage unit as a backup power supply, and bidirectional conversion is realized through a bidirectional converter. The battery energy storage unit supplies power to the load through the bidirectional converter. The micro-grid energy management system integrates a harmonic suppression module, a load prediction module and a transient response control module, and dynamically adjusts the power supply proportion of the diesel generator and the energy storage unit. The power distribution system accesses the mains, wind power or photovoltaic power as the main power supply, and switches to the diesel generator power supply mode when the main power supply fails. The bidirectional converter performs power conversion: when the diesel generator supplies power, it converts alternating current into direct current suitable for the energy storage unit; when the energy storage unit supplies power, it converts direct current into alternating current required by the load. The specific embodiment of the present application can realize seamless switching of multiple energy sources, the energy storage unit can suppress power fluctuations, the bidirectional converter can ensure flexible conversion of power forms, the micro-grid energy management system can optimize energy distribution efficiency, and the power supply reliability can be improved.

[0025] In a further embodiment of the present application: the harmonic suppression module includes: a harmonic analysis unit, a reverse harmonic injection unit. The harmonic analysis unit is used to monitor the harmonic components of the diesel generator and the load in real time; the reverse harmonic injection unit is used to generate a reverse signal with the same amplitude and opposite phase as the harmonic component through the bidirectional converter to offset the harmonic interference of the diesel generator. The harmonic suppression module is activated in the following scenarios: when the diesel generator supplies power alone; when the diesel generator and the energy storage unit supply power cooperatively and the harmonic distortion rate is detected to exceed the preset threshold. The harmonic suppression module continuously monitors the harmonic spectrum of the diesel generator and the load through the harmonic analysis unit. The reverse harmonic injection unit generates a reverse harmonic signal through the bidirectional converter to accurately offset the original harmonic component. The harmonic suppression module can be activated when the diesel generator operates independently or cooperatively or when the harmonic distortion rate exceeds the standard. The specific embodiment of the present application can eliminate the inherent harmonic interference of the diesel generator, avoid damage to the load equipment due to harmonics, and maintain the purity of the grid voltage waveform.

[0026] In a further embodiment of the present application: the load prediction module comprises: an AI algorithm unit, an energy storage pre-scheduling unit. The AI algorithm unit can predict the load power trend in the future time period based on historical load data, real-time working condition data and environmental parameters. The energy storage pre-scheduling unit can generate the charging and discharging strategy of the energy storage unit according to the prediction result, and increase the state of charge of the energy storage unit before the load power rises, or reduce the charging power before the load power drops. When the system is connected to the main power supply of municipal power / wind and light, the load prediction module can be activated and used to optimize the scheduling of the energy storage unit; when it is detected that the load type is a nonlinear or impact device, the load prediction module can also be activated and used to predict the instantaneous power demand. The AI algorithm unit of the load prediction module can fuse historical load curve, real-time working condition and temperature and humidity parameters to predict the future load power trend. The energy storage pre-scheduling unit can develop a charging and discharging plan based on the prediction result, increase the state of charge of the energy storage before the load rises, and reduce the charging power before the load drops. The module is activated when the main power supply is connected or the impact load is detected. The specific embodiment of the present application can predict the load trend, optimize the energy storage charging and discharging time, reduce the start-stop frequency of the diesel generator, and prolong the service life of the equipment.

[0027] In a further embodiment of the present application: the transient response control module comprises: an impact load detection unit, an ultra-fast charging and discharging unit. The impact load detection unit is used to identify the trigger of the impact load by real-time acquisition of the current rate of change at the load end and the device control signal. The ultra-fast charging and discharging unit is used to increase the output power of the energy storage unit to a preset excess power greater than the rated power during the action of the impact load, and limit the duration to prevent overload. The transient response control module will be activated when the instantaneous power change rate exceeds the preset threshold or the device emergency stop or high energy release instruction is received. The transient response control module identifies the impact load trigger through the current rate of change and the device control signal. The ultra-fast charging and discharging unit increases the output power of the energy storage unit to above the rated value when the load mutates, and strictly limits the duration. The transient response control module is activated when the power change rate exceeds the standard or the emergency stop instruction is received. The specific embodiment of the present application can quickly respond to the power demand of the impact load, prevent the diesel generator from overloading and shutting down, and ensure the continuous operation of the key equipment.

[0028] In further embodiments of the application: the harmonic suppression module, the load prediction module and the transient response control module are cooperatively controlled by the micro-grid energy management system, specifically including: when the load prediction module predicts that the impact load is about to start, the transient response control module is activated in advance to enter the standby state, and the harmonic suppression module is started synchronously to offset the harmonic distortion that may be caused by the diesel generator and the load. When the main power supply of the mains / wind / solar power is switched to the diesel generator for power supply, the load prediction module and the harmonic suppression module are linked to dynamically adjust the output proportion of the energy storage unit to suppress voltage fluctuation. When the load prediction module predicts the start of the impact load, the transient response control module is awakened in advance to standby, and the harmonic suppression module is started synchronously. When the main power supply is switched to the diesel generator, the load prediction module and the harmonic suppression module are linked to adjust the output proportion of the energy storage. The specific embodiments of the application can avoid voltage flicker, shorten the power supply switching interruption time, and maintain the stability of sensitive load power supply.

[0029] In further embodiments of the application: the cooperative work of the harmonic suppression module and the transient response control module includes: during the action of the impact load, the transient response control module increases the output power of the energy storage unit, while the harmonic suppression module suppresses the harmonic components caused by power mutation in real time, ensuring the stability of the voltage and frequency at the load end; when the diesel generator is distorted due to load mutation, the harmonic suppression module and the energy storage unit are cooperatively compensated for reactive power to reduce the harmonic emission of the diesel generator. During the action of the impact load, the transient response control module increases the energy storage power output, and the harmonic suppression module synchronously offsets the harmonics caused by power mutation. When the diesel generator is distorted due to load mutation, the harmonic suppression module and the energy storage unit jointly compensate for reactive power. The specific embodiments of the application can double control and suppress frequency oscillation, reduce the harmonic emission intensity of the diesel generator, and are beneficial to environmental protection.

[0030] In a further embodiment of the present application: the cooperation of the load prediction module and the transient response control module includes: the load prediction module predicts the triggering time point of the impact load according to the AI algorithm, and sends a preloading instruction to the transient response control module in advance, so that the SOC (or more accurately, the output power capability) of the energy storage unit is improved to a preset threshold. After the impact load ends, the load prediction module optimizes the power recovery rate of the transient response control module in combination with historical data to avoid secondary power impact. The load prediction module sends a preloading instruction to the transient response control module, so that the output capability of the energy storage unit is improved to a preset threshold. After the impact load ends, the power recovery rate is optimized based on historical data. The specific embodiment of the present application can avoid sudden rise and fall of the power of the energy storage unit, reduce the loss of battery life, and prevent secondary impact from causing system instability. In a further embodiment of the present application: the microgrid energy management system further includes a dynamic priority allocation unit, which marks critical loads and non-critical loads according to load types. When the system power supply capacity is insufficient, the non-critical load is cut off first, and through the cooperative control of the harmonic suppression module, the load prediction module and the transient response control module, the power supply quality and continuity of the critical load are guaranteed. The dynamic priority allocation unit marks the core equipment as a critical load and the lighting system as a non-critical load. When the power supply is insufficient, the non-critical load is cut off, and the three modules cooperate to guarantee the voltage waveform and power supply continuity of the critical load. The specific embodiment of the present application can realize the hierarchical power protection of the load, the power supply quality of the core equipment is not affected by system fluctuations, and the survival ability of the microgrid is improved.

[0031] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can make equivalent replacements or changes to the technical solutions and inventive concepts of the present application within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A diesel storage intelligent microgrid system, characterized in that, Comprise: A diesel generator as a backup power source, connected to a battery energy storage unit through a bidirectional converter, for charging the energy storage unit or providing power in case of power shortage; A battery energy storage unit connected to the load through a bidirectional converter, for storing and supplying power to the load; A micro-grid energy management system for dynamically coordinating the output ratio of the diesel generator and the energy storage unit, The micro-grid energy management system integrates: A harmonic suppression module for suppressing harmonic interference generated by the diesel generator; A load prediction module for predicting the trend of load power changes; A transient response control module for responding to transient power surges of the load; A power distribution system configured with a multi-source input switching interface for connecting to the mains, wind or solar power as the main power source, and switching to diesel generator power supply mode when the main power supply does not meet the requirements; The bidirectional converter can realize the following functions: When the diesel generator is powered, convert the power into charging current for the energy storage unit and suppress harmonic interference; When the energy storage unit is powered, convert the direct current into alternating current required by the load and dynamically adapt to the load power demand.

2. The apparatus of claim 1, wherein The harmonic suppression module includes: a harmonic analysis unit that monitors the harmonic components of the diesel generator and the load in real time; a reverse harmonic injection unit that generates a reverse signal with the same amplitude and opposite phase as the harmonic component to cancel the harmonic interference of the diesel generator; the harmonic suppression module is activated in the following scenarios: when the diesel generator is powered alone; when the diesel generator and the energy storage unit are powered together and the harmonic distortion rate is detected to exceed the preset threshold.

3. The apparatus of claim 1, wherein The load prediction module includes: an AI algorithm unit that predicts the trend of load power changes in the future time period based on historical load data, real-time operating condition data and environmental parameters; an energy storage pre-scheduling unit that generates a charging and discharging strategy for the energy storage unit based on the prediction results, and increases the state of charge of the energy storage unit before the load power rises, or reduces the charging power before the load power drops; the load prediction module is activated in the following scenarios: when the system is connected to the mains / wind-solar main power source, to optimize the scheduling of the energy storage unit; when the load type is detected to be a nonlinear or impact device, to predict the transient power demand.

4. The apparatus of claim 1, wherein The transient response control module includes: an impact load detection unit that identifies the trigger of the impact load by real-time acquisition of the current change rate at the load end and the device control signal; a super-fast charging and discharging unit that increases the output power of the energy storage unit to a preset excess power greater than the rated power during the action of the impact load, and limits the duration to prevent overload; the transient response control module is activated in the following scenarios: when the transient power change rate is detected to exceed the preset threshold; when the device emergency stop or high energy release instruction is received.

5. The apparatus of claim 1, wherein The harmonic suppression module, the load prediction module and the transient response control module are cooperatively controlled by the micro-grid energy management system, specifically including: when the load prediction module predicts that the impact load is about to start, the transient response control module is activated in advance to enter the standby state, and the harmonic suppression module is started synchronously to offset the harmonic distortion caused by the diesel generator and the load; when the city power / wind and light power main power is switched to the diesel generator power supply, the load prediction module and the harmonic suppression module are linked to dynamically adjust the output proportion of the energy storage unit to suppress voltage fluctuation.

6. The apparatus of claim 1, wherein The cooperative work of the harmonic suppression module and the transient response control module includes: during the action of the impact load, the transient response control module increases the output power of the energy storage unit, while the harmonic suppression module suppresses the harmonic component caused by the power mutation in real time, ensuring the stability of the voltage and frequency at the load end; when the diesel generator causes output distortion due to load mutation, the harmonic suppression module and the energy storage unit cooperatively compensate the reactive power to reduce the harmonic emission of the diesel generator.

7. The apparatus of claim 1, wherein The cooperative work of the load prediction module and the transient response control module includes: the load prediction module predicts the trigger time point of the impact load according to the AI algorithm, and sends a preloading instruction to the transient response control module in advance, so that the SOC (or more accurately, the output power capability) of the energy storage unit is increased to a preset threshold; after the impact load ends, the load prediction module optimizes the power recovery rate of the transient response control module combined with historical data to avoid secondary power impact.

8. The apparatus of claim 1, wherein The micro-grid energy management system further includes: a dynamic priority allocation unit that marks key loads and non-key loads according to load types; when the system power supply capacity is insufficient, the non-key loads are preferentially cut off, and the power supply quality and continuity of the key loads are guaranteed through the cooperative control of the harmonic suppression module, the load prediction module and the transient response control module.