A laboratory microgrid management system and method

Abstract

The application discloses a laboratory micro-grid management system and method, which comprises the following steps: detecting the current value of an incoming line in real time based on a current detection unit of the incoming line end of a factory; presetting a plurality of current threshold values; controlling the working states of an energy storage system and an energy consumption system according to the current threshold interval in which the current value of the incoming line is located; and performing hierarchical allocation management on the electric energy fed back by a dynamometer; and the application adopts an intelligent electric energy allocation strategy, so that the electric energy fed back by the dynamometer does not need to be fed back to a power grid, thereby fundamentally avoiding the harmonic pollution problem caused by the feedback electric energy to the power grid, and meanwhile, there is no need to apply for a power feeding approval to a relevant department.

Description

Technical Field

[0001] This application relates to the field of microgrid power management technology, and in particular to a laboratory microgrid management system and method. Background Technology

[0002] A dynamometer is a device used to measure the power of machinery. It is widely used in power system testing in the automotive, aerospace, and marine industries, and mainly includes chassis dynamometers, engine dynamometers, and motor dynamometers, all with electrical energy feedback capabilities. During operation, the object being tested drives the loading motor, generating a significant amount of feedback electrical energy. How to efficiently and environmentally manage this feedback electrical energy has always been a crucial technical challenge for dynamometer laboratories.

[0003] Traditional dynamometer laboratories typically handle the electrical energy fed back from the dynamometer using two methods. The first method involves feeding the energy back to the power grid via a four-quadrant frequency converter or energy feedback module. The second method involves dissipating the energy by converting it into heat through a resistive load.

[0004] However, both of the aforementioned traditional methods have significant drawbacks and shortcomings. The main disadvantages of feeding electrical energy back to the grid are as follows: First, many factory power supplies use a high-voltage-to-mains conversion method, and the power supply system itself does not support reverse energy feedback to the grid; second, the electrical energy fed back by the dynamometer contains a large number of harmonics, and direct feedback to the grid will cause serious harmonic pollution, affecting the grid's power quality; third, feeding electrical energy back to the grid requires reporting to and obtaining approval from the relevant power management department, and the amount of energy fed back needs to be determined. However, the usage of the dynamometer at each time period cannot be predetermined, making it impossible to accurately control and predict the amount of energy fed back, which brings great difficulties to actual operation.

[0005] The method of converting electrical energy into heat energy through resistance also has significant drawbacks: First, this method results in a huge waste of electrical energy, with a large amount of electrical energy being converted into heat energy and dissipated, significantly increasing the usage and operating costs of the dynamometer; Second, in some laboratory settings where space is limited, the resistor operates at very high temperatures and requires a large heat dissipation space, which many laboratories lack; Third, resistors operate at high temperatures for extended periods, resulting in a limited lifespan and requiring periodic replacement, further increasing maintenance costs and operational burden. Summary of the Invention

[0006] To overcome the above-mentioned shortcomings, the purpose of this application is to provide a laboratory microgrid management system and method, thereby effectively solving the above-mentioned technical problems.

[0007] To achieve the above objectives, this application adopts the following technical solution: This application provides a laboratory microgrid management method, including the following: The current detection unit at the factory's incoming line end detects the incoming current value in real time; Preset multiple current threshold levels; Based on the current threshold range of the incoming current value, the working status of the energy storage system and the energy consumption system is controlled, and the electrical energy fed back by the dynamometer is managed and distributed in a hierarchical manner.

[0008] Furthermore, The preset multi-level current thresholds include: Set three current thresholds, a, b, and c, respectively. The three current thresholds satisfy 0 <a<b<c, The values ​​of the three current thresholds a, b, and c are set and adjusted via the control unit.

[0009] Furthermore, The control of the operating status of the energy storage system and the energy consumption system based on the current threshold range of the incoming current value includes: When the incoming current value is detected to be less than the current threshold a, the energy-consuming system is controlled to start discharging, and the energy storage system is controlled to start charging until it is fully charged. When the detected incoming current value is greater than the current threshold a and less than the current threshold b, the energy-consuming system is controlled to stop discharging, and the energy storage system is controlled to start charging until it is fully charged. When the detected incoming current value is greater than the current threshold b and less than the current threshold c, the energy-consuming system is controlled to stop discharging, and the energy storage system is controlled to stop charging and discharging. When the incoming current value is detected to be greater than the current threshold c, the energy-consuming system is controlled to stop discharging, and the energy storage system is controlled to start discharging.

[0010] Furthermore, the control of the energy-consuming system to start discharging also includes: the discharge current in the energy-consuming system is dynamically adjusted by the system in real time.

[0011] Furthermore, when the energy storage system is fully charged and can no longer consume the electrical energy generated by the dynamometer, causing the incoming current to decrease to below the current threshold a, it automatically switches to the working mode when the incoming current value is less than the current threshold a.

[0012] Furthermore, the electrical energy fed back by the dynamometer is output as DC power through the energy feedback unit. After being processed by a filter, the DC power is sent to the DC bus to charge the energy storage system or be consumed by the energy consumption system.

[0013] This application also provides a laboratory microgrid management system, which is implemented based on the above-described laboratory microgrid management method, and the management system includes: Control unit, dynamometer system, energy feedback unit, energy storage system and energy consumption system.

[0014] Furthermore, the dynamometer system includes any one or more devices with electrical energy feedback, such as a chassis dynamometer, an engine dynamometer, and a motor dynamometer.

[0015] Beneficial effects Compared with the prior art, the present invention has the following beneficial technical effects: This invention employs an intelligent power distribution strategy, eliminating the need for dynamometer feedback to the power grid. This fundamentally avoids harmonic pollution caused by feedback power and eliminates the need for approval from relevant authorities for power supply. Furthermore, this invention does not rely solely on resistor heating to consume energy. Instead, it prioritizes energy storage through an energy storage system, releasing power to supplement supply when there is a significant power shortage in the plant area. This significantly improves energy utilization efficiency and effectively reduces the operating and usage costs of the dynamometer. Simultaneously, this invention reduces the usage time and power consumption of resistor-based energy-consuming equipment, lowers space requirements, and extends the lifespan of related equipment. Attached Figure Description

[0016] The accompanying drawings are provided to illustrate the technical solutions of this disclosure and form part of the specification. They are used together with the embodiments of this disclosure to explain the technical solutions of this disclosure and do not constitute a limitation on the technical solutions of this disclosure. The shapes and sizes of the components in the drawings do not reflect actual proportions and are only intended to illustrate the content of this application.

[0017] Figure 1 A schematic diagram of the topology of the laboratory microgrid management system provided in this application embodiment. Detailed Implementation

[0018] The above-described solution will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of this application. The implementation conditions used in the embodiments may be further adjusted according to the conditions of specific manufacturers, and the implementation conditions not specified are generally those in routine experiments.

[0019] Unless otherwise defined, the technical or scientific terms used in the embodiments of this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. In this document, "electrical connection" includes the situation where constituent elements are connected together by an element having some electrical function. There is no particular limitation on the "electrically functioning element," as long as it enables the transmission and reception of electrical signals between the connected constituent elements. An "electrically functioning element" can be, for example, an electrode or wiring, a switching element such as a transistor, or other functional elements such as a resistor, inductor, or capacitor. "Up," "down," "left," and "right" are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0020] In this application, the terms "upper," "lower," "inner," "middle," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0021] Example like Figure 1 As shown, the laboratory microgrid management system provided in this embodiment of the invention mainly includes: a power grid, a transformer, a current sensor, a controller, a driver, an energy feedback unit, a filter, an energy storage system, an energy consumption system, multiple electrical devices, a loading motor, and a test object.

[0022] The power grid supplies power to the entire laboratory system via transformers. A current sensor is installed at the incoming line terminal in the plant area to monitor the magnitude of the incoming current in real time. The detection signal from the current sensor is fed back to the controller, serving as the basis for the controller's decision-making. The controller is the core control unit of the entire system, responsible for receiving the feedback signal from the current sensor and issuing control signals to the energy storage and energy consumption systems according to the preset control strategy.

[0023] The dynamometer system mainly includes a driver, a loading motor and a test object. The test object drives the loading motor to operate during the test process, and the generated alternating current is converted into direct current output through the driver and the energy feedback unit. The direct current output by the energy feedback unit is filtered by a filter and then transmitted to the DC bus. An energy storage system and an energy consumption system are connected to the DC bus, for storing or consuming the electric energy fed back by the dynamometer. At the same time, the DC bus is also connected to the plant AC bus, and the electric energy generated by the dynamometer can be directly supplied to the electric equipment 1 to electric equipment n in the plant for use.

[0024] The specific implementation process of the laboratory microgrid management method of the present invention is described in detail below: First, perform system parameter configuration: three current thresholds a, b, and c are preset in the controller, satisfying the relationship of 0<a<b<c. The specific values of these three thresholds can be set and adjusted according to factors such as the actual power consumption situation of the laboratory, the power level of the dynamometer, and the capacity of the energy storage system, so as to adapt to different application scenarios. For example, for a dynamometer system with a relatively small power, the thresholds can be set to be relatively small; for a dynamometer system with a relatively large power, the thresholds need to be increased accordingly. The principle for setting the thresholds is to ensure that the system can reasonably distribute electric energy under various working conditions, not only ensuring the full utilization of electric energy, but also avoiding adverse impacts on the power grid.

[0025] After the system is started, the current sensor detects the current value at the incoming line end of the plant in real time, and continuously feeds the detection result back to the controller. The controller judges which threshold interval the detected real-time incoming line current value falls into, and then executes the corresponding control strategy. The entire control process is real-time and dynamic, and the controller will continuously monitor the current change and adjust the control strategy in time.

[0026] The first working mode: when the controller detects that the incoming line current value is less than the current threshold a, it indicates that the generated power of the dynamometer at this time is far greater than the total power consumption of all electric equipment in the plant, and the dynamometer generates a large amount of excess electric energy. In this case, the controller sends control instructions to both the energy storage system and the energy consumption system at the same time. On the one hand, the energy storage system is controlled to start the charging mode, so as to store the excess electric energy fed back by the dynamometer into the energy storage system; on the other hand, the energy consumption system is controlled to start the discharging mode, so as to consume the remaining electric energy that cannot be fully absorbed by the energy storage system. Under this working mode, the discharging current of the energy consumption system is not a fixed value, but is dynamically adjusted in real time by the system according to factors such as the current generated power, power consumption, and the charging state of the energy storage system, so as to ensure reasonable distribution of electric energy and stable operation of the system. After the energy storage system is fully charged, if there is still excess electric energy, all of it will be consumed by the energy consumption system.

[0027] The second operating mode: When the controller detects that the incoming current value is greater than the current threshold 'a' but less than the current threshold 'b', it indicates that the dynamometer's power generation is greater than the power consumption in the plant area, but the difference is not significant, resulting in relatively little excess energy. In this case, the controller sends a command to the energy-consuming system to stop discharging and simultaneously sends a command to the energy storage system to start charging. At this time, the energy fed back by the dynamometer first meets the needs of the plant's electrical equipment, and the remaining energy is used to charge the energy storage system until it is fully charged. In this mode, because there is little excess energy, there is no need to start the energy-consuming system, thus avoiding unnecessary energy waste. It should be noted that during the operation of the second operating mode, if the dynamometer continues to generate electricity after the energy storage system is fully charged, the energy storage system will be unable to absorb more energy, leading to a further decrease in the incoming current. When the incoming current decreases below the current threshold 'a', the system will automatically determine and switch to the first operating mode, starting the energy-consuming system to consume the excess energy and ensure stable system operation.

[0028] The third operating mode: When the controller detects that the incoming current value is greater than the current threshold b but less than the current threshold c, it indicates that the dynamometer's power generation is less than the power consumption within the plant area. The electrical energy generated by the dynamometer is insufficient to meet the needs of all electrical equipment in the plant area, requiring supplemental power from the grid. In this case, the controller sends a command to the energy-consuming system to stop discharging, and simultaneously sends commands to the energy storage system to stop charging and discharging. At this time, all the electrical energy generated by the dynamometer is directly supplied to the electrical equipment within the plant area, with the shortfall supplemented by the grid through the incoming line. The energy storage system is in standby mode, neither charging nor discharging, waiting for a more suitable charging and discharging opportunity. In this operating mode, the dynamometer's electrical energy is directly utilized, and the energy storage system avoids unnecessary charging and discharging cycles, which helps extend the lifespan of the energy storage system.

[0029] The fourth operating mode: When the controller detects that the incoming current value is greater than the current threshold c, it indicates that the dynamometer's power generation is far less than the plant's power consumption, resulting in a significant power shortage and requiring a large amount of electricity to be drawn from the grid. In this situation, the controller sends a command to the energy-consuming system to stop discharging, and simultaneously sends a command to the energy storage system to start discharging. At this time, the electricity generated by the dynamometer and the electricity released by the energy storage system are jointly supplied to the electrical equipment in the plant, thereby reducing the amount of electricity drawn from the grid, lowering peak electricity consumption, and achieving peak shaving and valley filling. This operating mode fully utilizes the electricity previously stored in the energy storage system, improving overall energy utilization efficiency and also helping to reduce electricity costs.

[0030] It is important to emphasize that the switching between the four operating modes is automatic, smooth, and seamless. The controller continuously monitors changes in the incoming current in real time. Once the current value crosses a certain threshold boundary, the system immediately executes the corresponding control strategy without manual intervention. The entire switching process is fast and stable, and will not affect the normal operation of the electrical equipment or dynamometer.

[0031] In this invention, the dynamometer includes, but is not limited to, various testing devices with electrical energy feedback functions, such as chassis dynamometers, engine dynamometers, and motor dynamometers. Regardless of the type of dynamometer, as long as it can provide electrical energy feedback, the management method of this invention can be applied for energy management.

[0032] The energy storage system can employ various types of energy storage devices, including but not limited to lithium-ion battery packs, lead-acid battery packs, supercapacitors, and flywheel energy storage devices. The capacity of the energy storage system can be configured according to actual needs; the larger the capacity, the more electrical energy it can store, and the more significant the peak shaving and valley filling effect.

[0033] The energy-consuming system can employ various types of energy-consuming devices, including but not limited to resistive load groups and water-cooling systems. The power rating of the energy-consuming system should match the maximum power of the dynamometer to ensure that all excess electrical energy can be consumed when needed.

[0034] The filter described above is used to filter the DC power output from the energy feedback unit, removing ripple and harmonics, improving power quality, and ensuring that the power quality delivered to the DC bus meets requirements. The filter can be of various types, such as LC filter circuits or active filter circuits.

[0035] The controller can be any type of control device, such as a programmable logic controller (PLC), industrial control computer, microcontroller (MCU), or digital signal processor (DSP). The controller should have sufficient computing power and response speed to ensure real-time processing of the current sensor's feedback signal and timely issuance of control commands.

[0036] The current sensor should possess sufficient accuracy and response speed to accurately and in real-time detect changes in the incoming current. The current sensor's range should cover the maximum current range that the system may experience.

[0037] The working principle of this invention is as follows: Based on the principles of energy conservation and power balance, by monitoring the incoming current of the power grid in real time, the balance between the power generation of the dynamometer and the power consumption of the plant area is indirectly determined. Then, according to different power balance states, different power allocation strategies are adopted to achieve optimal power allocation. When the power generation is much greater than the power consumption, both energy storage and energy consumption are used to handle the excess power; when the power generation is slightly greater than the power consumption, energy storage is given priority; when the power generation is less than the power consumption, the generated power is used directly; when the power generation is much less than the power consumption, the stored energy is released to supplement the power supply. This hierarchical management strategy ensures the stability of the system while maximizing the efficiency of power utilization.

[0038] Compared with the prior art, the beneficial effects of the present invention are also reflected in the following aspects: First, the present invention completely avoids the various problems caused by feeding electrical energy back to the power grid. Since the electrical energy fed back by the dynamometer is entirely consumed in the laboratory's internal microgrid and does not need to be fed back to the public power grid, there is no problem of harmonic pollution of the power grid, nor is it necessary to apply for power supply approval from the power department, which greatly simplifies the operation process and reduces management costs.

[0039] Secondly, this invention significantly improves energy utilization efficiency. Traditional resistive energy consumption methods convert all electrical energy into heat energy, resulting in waste. In contrast, this invention stores excess electrical energy through an energy storage system, releasing it during peak electricity demand. This achieves a spatial and temporal transfer of electrical energy, turning waste into treasure and greatly reducing overall electricity costs. Actual calculations show that systems using this invention can save over 30% of energy consumption, demonstrating significant economic benefits.

[0040] Third, this invention reduces the space requirements. Since the energy-consuming system does not need to operate continuously at full power, but only starts after the energy storage system is fully charged, and the operating time and power are greatly reduced, the requirements for heat dissipation space are also reduced accordingly, making it suitable for use in laboratories with limited space.

[0041] Fourth, this invention extends the lifespan of the equipment. The operating time and power consumption of the energy-consuming system are significantly reduced, avoiding prolonged high-temperature operation, thus significantly extending its lifespan and correspondingly reducing maintenance and replacement costs. Simultaneously, the charging and discharging of the energy storage system are optimized and controlled, avoiding frequent charging and discharging, which also contributes to extending its lifespan.

[0042] Fifth, the system of this invention has good scalability and adaptability. The current threshold can be flexibly adjusted, and the capacity of the energy storage system and the energy consumption system can also be configured according to actual needs, enabling it to adapt to dynamometer laboratories of different sizes and power levels. The system adopts a modular design, with each subsystem relatively independent, facilitating maintenance and upgrades.

[0043] Sixth, the control strategy of this invention is simple, reliable, and easy to implement. The entire control system is based on a clear current threshold judgment logic, with a simple algorithm that does not require complex calculations. It does not place high demands on the performance of the controller, thus reducing system costs while improving system reliability and stability.

[0044] The above embodiments are only for illustrating the technical concept and features of this application, and are intended to enable those skilled in the art to understand the content of this application and implement it accordingly. They should not be used to limit the scope of protection of this application. All equivalent changes or modifications made in accordance with the spirit and essence of this application should be included within the scope of protection of this application.

Claims

1. A laboratory microgrid management method, characterized in that: Including the following: The current detection unit at the factory's incoming line end detects the incoming current value in real time; Preset multiple current threshold levels; Based on the current threshold range of the incoming current value, the working status of the energy storage system and the energy consumption system is controlled, and the electrical energy fed back by the dynamometer is managed and distributed in a hierarchical manner.

2. The laboratory microgrid management method according to claim 1, characterized in that: The preset multi-level current thresholds include: Set three current thresholds, a, b, and c, respectively. The three current thresholds satisfy 0 <a<b<c, The values ​​of the three current thresholds a, b, and c are set and adjusted via the control unit.

3. The laboratory microgrid management method according to claim 2, characterized in that: The control of the operating status of the energy storage system and the energy consumption system based on the current threshold range of the incoming current value includes: When the incoming current value is detected to be less than the current threshold a, the energy-consuming system is controlled to start discharging, and the energy storage system is controlled to start charging until it is fully charged. When the detected incoming current value is greater than the current threshold a and less than the current threshold b, the energy-consuming system is controlled to stop discharging, and the energy storage system is controlled to start charging until it is fully charged. When the detected incoming current value is greater than the current threshold b and less than the current threshold c, the energy-consuming system is controlled to stop discharging, and the energy storage system is controlled to stop charging and discharging. When the incoming current value is detected to be greater than the current threshold c, the energy-consuming system is controlled to stop discharging, and the energy storage system is controlled to start discharging.

4. The laboratory microgrid management method according to claim 3, characterized in that: The control of the energy consumption system to initiate discharge also includes: The discharge current in the energy-consuming system is dynamically adjusted in real time by the system.

5. The laboratory microgrid management method according to claim 3, characterized in that: When the energy storage system is fully charged and can no longer consume the electrical energy generated by the dynamometer, causing the incoming current to decrease to below the current threshold a, it automatically switches to the working mode when the incoming current value is less than the current threshold a.

6. The laboratory microgrid management method according to claim 1, characterized in that: The electrical energy fed back by the dynamometer is output as DC power through the energy feedback unit. After being processed by a filter, the DC power is sent to the DC bus to charge the energy storage system or be consumed by the energy consumption system.

7. A laboratory microgrid management system, characterized in that: The management system is implemented based on the laboratory microgrid management method according to any one of claims 1-6, and the management system includes: Control unit, dynamometer system, energy feedback unit, energy storage system and energy consumption system.

8. The laboratory microgrid management system according to claim 7, characterized in that: The dynamometer system includes any one or more devices with electrical energy feedback, such as chassis dynamometer, engine dynamometer, and motor dynamometer.

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