A load balancing system for a meter box

Abstract

This utility model relates to the field of load balancing technology for electricity meter boxes, and discloses an electricity meter box load balancing system, including an intelligent switch module, a current detection module, and a control module. The input terminal of the intelligent switch module is electrically connected to a three-phase bus, and the output terminal of the intelligent switch module is electrically connected to a user branch. The intelligent switch module is also electrically connected to the current detection module. The control module is signal-connected to the intelligent switch module, and the output terminal of the current detection module is signal-connected to a signal conditioning module. The signal conditioning module is a signal conditioning circuit, and the output terminal of the signal conditioning module is signal-connected to a communication module. The communication module is bidirectionally signal-connected to a host computer. In this utility model, by connecting the output terminals of the three-phase solid-state relay group to user branches respectively, and by controlling the independent on / off switching or phase sequence switching of each user branch through the control module, centralized management of multi-user loads is achieved.

Description

Technical Field

[0001] This utility model relates to the field of load balancing technology for electric meter boxes, and in particular to a load balancing system for electric meter boxes. Background Technology

[0002] In current low-voltage power distribution systems, meter boxes serve as critical nodes in power distribution, and their load balancing directly impacts power supply reliability and equipment lifespan. With the development of smart grid technology, remote monitoring and switch control technologies have matured, providing a foundation for the intelligent transformation of meter boxes. However, existing technologies largely focus on monitoring the electricity consumption of single users, lacking dynamic load optimization schemes for multi-user centralized meter boxes. Therefore, there is a need to develop a meter box load balancing system. Utility Model Content

[0003] To overcome the above shortcomings, this utility model provides a load balancing system for electricity meter boxes, which aims to improve the existing technology that focuses on electricity monitoring of single users and lacks a dynamic load optimization scheme for centralized electricity meter boxes for multiple users.

[0004] To achieve the above objectives, this utility model adopts the following technical solution: a load balancing system for an electricity meter box, comprising an intelligent switch module, a current detection module, and a control module. The input terminal of the intelligent switch module is electrically connected to a three-phase bus, the output terminal of the intelligent switch module is electrically connected to a user branch, the intelligent switch module is electrically connected to the current detection module, the control module is signal-connected to the intelligent switch module, the output terminal of the current detection module is signal-connected to a signal conditioning module, the signal conditioning module is a signal conditioning circuit, the output terminal of the signal conditioning module is signal-connected to a communication module, and the communication module is bidirectionally signal-connected to a host computer.

[0005] The above technical solutions can provide data for load balancing adjustment, enabling the system to accurately determine whether the three-phase current is unbalanced. Furthermore, the bidirectional connection between the communication module and the host computer allows managers to remotely monitor the load status of the meter box, achieving load balancing adjustment without on-site operation and improving maintenance efficiency.

[0006] As a further description of the above technical solution:

[0007] The output signal of the communication module is connected to the input of the smart meter. The communication module uses LoRa wireless communication and is used to upgrade old distribution cabinets that are difficult to modify.

[0008] The above technical solution: the LoRa design to replace RS-485 can solve the wiring problem of old power distribution cabinet renovation, reduce the difficulty and cost of renovation, and at the same time, data collaboration can be achieved through the connection of the communication module with the smart meter.

[0009] As a further description of the above technical solution:

[0010] The communication module is bidirectionally connected to the control module, the control module is bidirectionally connected to the heat dissipation module, and the heat dissipation module is signal-connected to the intelligent switch module.

[0011] Through the above technical solution, the control module can send real-time load status, equipment operating parameters, heat dissipation module temperature, and other data to the host computer or smart meter via the communication module, thereby realizing remote monitoring and data recording. At the same time, the communication module can receive remote commands from the host computer and then feed them back to the control module for execution, improving the system's intelligence and flexibility. It not only meets the local automatic balancing requirements but also supports remote intervention and data analysis, adapting to the management mode of the smart grid. Through temperature closed-loop control, it provides real-time protection for the smart switch module.

[0012] As a further description of the above technical solution:

[0013] The intelligent switch module consists of a three-phase solid-state relay group, each group containing three bidirectional thyristors. The bidirectional thyristors can be replaced with IGBT modules, which are suitable for higher frequency switching scenarios.

[0014] The above technical solution uses a bidirectional thyristor, BTA41-600B, which is compatible with the conventional loads of conventional user branches. The design without mechanical contacts ensures spark-free switching and a long lifespan, meeting the stable operation requirements of the meter box. When needed, it can be replaced with an IGBT module, which utilizes its high-frequency switching characteristics to adapt to the rapid adjustment requirements of high-frequency load fluctuations in industrial scenarios, avoiding three-phase imbalance caused by switching lag.

[0015] As a further description of the above technical solution:

[0016] The input terminals of the three-phase solid-state relay group are connected in parallel to the three-phase bus, and the output terminals are respectively connected to the user branches. The trigger electrode of the bidirectional thyristor is directly connected to the GPIO pin of the main control chip of the control module.

[0017] The above technical solution enables independent phase sequence control of a single load, flexible adjustment of the three-phase load distribution, and direct output of trigger signals to the bidirectional thyristor via GPIO pins. No other conversion circuits are required, which reduces signal attenuation and delay, and ensures that the thyristor operates accurately under the command of the control module.

[0018] As a further description of the above technical solution:

[0019] The current detection module uses a Hall sensor array and is installed at the input and output terminals of each phase line of the three-phase bus.

[0020] The above technical solution allows for array-style installation to cover all phase lines, ensuring that the control module can obtain complete three-phase current data and provide comprehensive input for the load balancing algorithm.

[0021] As a further description of the above technical solution:

[0022] The Hall sensor is nested in the insulated copper busbar of the three-phase busbar and is used to collect the incoming and outgoing current of each phase line in real time.

[0023] The above technical solution can ensure the accuracy of current detection, and the insulation layer of the insulated copper busbar can prevent short circuits between the sensor and the busbar, while reducing external electromagnetic interference. Moreover, the current data collected in real time by the Hall sensor can provide a basis for dynamic adjustment of the control module.

[0024] As a further description of the above technical solution:

[0025] The heat dissipation module includes a temperature sensor, a heat sink, a cooling fan, and a fan drive circuit. The control terminal of the fan drive circuit is electrically connected to the control module, and the output terminal of the fan drive circuit is electrically connected to the cooling fan. The heat sink is attached to the heat dissipation surface of the three-phase solid-state relay group. The temperature sensor is installed close to the heat sink of the three-phase solid-state relay group and is used to monitor the temperature of the heat sink of the three-phase solid-state relay group. The temperature sensor is connected to the control module for signal transmission of heat sink temperature data in real time.

[0026] Through the above technical solution: the temperature sensor can transmit the real-time temperature of the solid-state relay heat sink to the control module as the basis for heat dissipation decision. Then, the control module can send a control signal to the heat dissipation module according to the temperature data to realize active heat dissipation and temperature protection of the three-phase solid-state relay group, avoid the relay performance degradation or burnout caused by overheating, ensure that the fan operates stably under the command of the control module, and quickly reduce the temperature of the heat sink through forced air cooling to improve heat dissipation efficiency.

[0027] This utility model has the following beneficial effects:

[0028] 1. In this utility model, the design of connecting the output terminals of the three-phase solid-state relay group to the user branches respectively, and the control module to independently switch or change the phase sequence of each user branch, realizes centralized management of multi-user loads. The Hall sensor array can monitor the incoming and outgoing currents of each phase line of the three-phase bus in real time, providing a basis for the decision of the control module. The control module can directly drive the bidirectional thyristor through the GPIO pin, which can quickly switch the phase sequence of the user branches, avoid overload line aging, increased energy consumption, and tripping risk caused by fixed allocation, and improve the utilization rate of idle lines.

[0029] 2. In this utility model, the intelligent switch module is used to realize the dynamic distribution of load. Combined with current detection and communication functions, the core effects of three-phase load balancing, improved power safety and efficiency, and support for intelligent management are achieved. It is suitable for meter box scenarios that require stable three-phase power supply. Through the synergistic effect of the components in the heat dissipation module, accurate temperature monitoring and efficient heat dissipation control of the three-phase solid-state relay group are realized, which ultimately ensures the stable operation of the intelligent switch module and provides temperature safety guarantee for the long-term reliable operation of the meter box load balancing system.

[0030] 3. In this utility model, data communication is achieved through wireless communication, which provides a foundation for intelligent functions such as remote monitoring of meter boxes, automatic load adjustment, and power consumption data analysis, and avoids the inability of old equipment to be connected to the smart grid system due to communication limitations. Attached Figure Description

[0031] Figure 1 This utility model provides a schematic block diagram of the system modules of a load balancing system for an electric meter box.

[0032] Figure 2 This is a schematic block diagram of the heat dissipation module of a load balancing system for an electric meter box proposed in this utility model. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0034] Reference Figure 1 This utility model provides an embodiment of a load balancing system for an electricity meter box, comprising an intelligent switch module, a current detection module, and a control module. The input terminal of the intelligent switch module is electrically connected to a three-phase bus, the output terminal of the intelligent switch module is electrically connected to a user branch, the intelligent switch module is electrically connected to the current detection module, the control module is signal-connected to the intelligent switch module, the output terminal of the current detection module is signal-connected to a signal conditioning module, the signal conditioning module is a signal conditioning circuit, the output terminal of the signal conditioning module is signal-connected to a communication module, and the communication module is bidirectionally signal-connected to a host computer.

[0035] Specifically, the current detection module, through its electrical connection with the intelligent switch module, can collect real-time current data from each user branch and the three-phase busbar via a Hall sensor. The current signal is then processed by the signal conditioning circuit in the signal conditioning module and uploaded to the host computer via the communication module, thereby enabling real-time monitoring of the load current of each phase in the meter box. Through the signal connection between the control module and the intelligent switch module, the intelligent switch module can be controlled to operate based on the current detection data or instructions issued by the host computer. The bidirectional connection to the host computer via the communication module allows for the uploading of real-time current data and switch status to the host computer, as well as the receipt of control instructions from the host computer.

[0036] Reference Figure 1 The output signal of the communication module is connected to the input of the smart meter. The communication module uses LoRa wireless communication and is used to upgrade old distribution cabinets that are difficult to modify.

[0037] Specifically, by connecting to the smart meter via a communication module, bidirectional data transmission can be achieved. Information from the load balancing system can be sent to the smart meter, while simultaneously receiving electricity consumption data from the smart meter. This supports the coordination of electricity metering and load management. LoRa is a low-power wide-area network technology, an existing technology that supports long-distance wireless communication, has strong anti-interference capabilities, and requires no wiring. In contrast, RS-485 is a wired differential transmission technology, also an existing technology, requiring the laying of signal cables. However, in the renovation of old distribution cabinets, problems such as aging cables, limited space, and high rewiring costs may arise. Therefore, using LoRa wireless communication to replace RS-485 wired connections avoids the construction difficulties of rewiring in old distribution cabinets and reduces the time and cost of renovation.

[0038] Reference Figure 1 The communication module and control module are bidirectionally connected, and the control module is bidirectionally connected to a heat dissipation module, which is then connected to the intelligent switch module. The intelligent switch module consists of a three-phase solid-state relay group, each containing three bidirectional thyristors. These bidirectional thyristors can be replaced with IGBT modules for higher frequency switching scenarios. The input terminals of the three-phase solid-state relay group are connected in parallel to the three-phase bus, and the output terminals are connected to the user branches. The trigger terminals of the bidirectional thyristors are directly connected to the GPIO pins of the main control chip of the control module. The current detection module uses a Hall sensor array, installed at the input and output terminals of each phase line of the three-phase bus. The Hall sensors are nested in the insulated copper busbars of the three-phase bus for real-time acquisition of the input and output currents of each phase line.

[0039] Specifically, the bidirectional connection between the communication module and the control module enables bidirectional data transmission. The communication module can send data such as the load status and balancing strategies of the control module to the host computer or smart meter. Simultaneously, the communication module can receive remote commands from the host computer or power consumption data from the smart meter, and then feed this data back to the control module for optimization decisions. This supports remote monitoring and collaborative control, improving the system's intelligence and operational flexibility. The bidirectional connection between the communication module and the heat dissipation module allows the control module to receive real-time temperature data from the heat dissipation module and output control commands to it, forming a closed-loop temperature control system. This ensures the smart switch module operates within a safe temperature range, preventing overheating damage and extending equipment lifespan. The heat dissipation module directly monitors the temperature status of the smart switch module, providing raw data for the control module's heat dissipation decisions. The selected bidirectional thyristor is model BTA41-600B (40A / 600V), with a conduction time of <1ms. As a contactless switch, the BTA41-600B eliminates mechanical contact wear, has a long lifespan, and is triggered to turn on or off by the GPIO signal of the control module. This enables phase sequence switching between the user branch and the three-phase bus. When needed, it can be replaced with an IGBT module, increasing the switching frequency to microsecond levels to adapt to more dynamic load balancing scenarios. The input terminals of the three-phase solid-state relay group are connected in parallel to the three-phase bus, while the output terminals are independently connected to the user branch, enabling independent phase sequence control of a single load. By controlling the conduction of different relays, the user branch can be flexibly allocated to the three phases, achieving dynamic adjustment of the load ratio of each phase. The control module outputs signals through GPIO pins, which can directly trigger the bidirectional thyristor to turn on or off, achieving fast switching of the user branch. The system features rapid switching, reducing intermediate conversion steps, improving switching response speed, and ensuring real-time load balancing adjustment. The Hall sensor used is the ACS712ELCTR-30A-T model, with a linear error of ±1.5%. It can detect the current of each phase line non-contactly through the Hall effect. The input and output terminals can simultaneously monitor the current of a single load. Furthermore, by embedding the Hall sensor in an insulated copper busbar with a spacing of ≥20mm, magnetic field interference can be avoided, ensuring detection accuracy. It can acquire the total three-phase current and the current of each user branch in real time, providing accurate input for the balancing algorithm of the control module.

[0040] Reference Figure 1 and Figure 2 The heat dissipation module includes a temperature sensor, a heat sink, a cooling fan, and a fan drive circuit. The control terminal of the fan drive circuit is electrically connected to the control module, and the output terminal of the fan drive circuit is electrically connected to the cooling fan. The heat sink is attached to the heat dissipation surface of the three-phase solid-state relay group. The temperature sensor is installed close to the heat sink of the three-phase solid-state relay group to monitor the temperature of the heat sink of the three-phase solid-state relay group. The temperature sensor is connected to the control module for signal transmission of heat sink temperature data in real time.

[0041] Specifically, the DS18B20 single-bus digital temperature sensor is selected, which can accurately collect the temperature of the heat sink, providing reliable data for heat dissipation control. The single-bus design simplifies wiring and saves limited space in the meter box. Through the output signal of the control module, the fan drive circuit can be turned on or off, thereby indirectly regulating the start, stop and speed of the cooling fan, realizing intelligent control of the cooling fan and avoiding unnecessary energy consumption. At the same time, the drive circuit can amplify the control signal, converting the weak electrical signal of the control module into the strong electrical signal required for fan operation, meeting the power requirements of the fan and providing operating power. The heat sink can quickly conduct and diffuse the heat generated by the relay during operation into the air through a large area of ​​metal, so that the heat of the relay is efficiently dissipated and the local temperature is not too high. The temperature sensor can directly collect and monitor the temperature of the heat sink on the three-phase solid-state relay group, making temperature monitoring more accurate and faster in response, ensuring that the control module can trigger the heat dissipation action in time to prevent the relay from overheating. The control module can dynamically adjust the heat dissipation strategy according to the real-time temperature data sent by the temperature sensor. When the temperature is >80℃, forced air cooling is activated, thus forming a closed-loop control to ensure that the relay always operates within a safe temperature range.

[0042] Working principle: First, during installation, it is necessary to ensure that the voltage difference between the three-phase busbars is less than 2%. Otherwise, the transformer tap changer needs to be adjusted first. During the commissioning phase, the priority weight of each user branch needs to be set through the host computer. During maintenance, the upstream circuit breaker must be disconnected first to prevent TRIAC from being triggered falsely. Hall sensors collect the current of each phase in real time. The control unit calculates the phase imbalance every 5 seconds. When the deviation is greater than 15%, the balancing strategy is triggered. The control unit selects the phase line with the highest load and sends a pulse signal through GPIO to turn off the corresponding TRIAC. At the same time, the TRIAC of the phase line with the lowest load is turned on. The switching process is less than 5ms. This dynamic balancing strategy can reduce the line loss rate and improve the transformer utilization rate.

[0043] The user branch circuit is quickly switched by a three-phase solid-state relay group to avoid voltage sags caused by sudden load changes. With the help of Hall sensors to monitor the load status of each phase in real time, the control module dynamically adjusts the connection relationship according to the preset algorithm to keep the three-phase current imbalance under long-term control. Since the three-phase load imbalance can cause the current of one phase to be too large, it may cause faults such as overheating of the wires, burning of the meter box, or even tripping. By dynamically balancing the load, single-phase overload can be avoided and safety hazards can be reduced.

[0044] Finally, it should be noted that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A load balancing system for an electricity meter box, comprising an intelligent switch module, a current detection module, and a control module, characterized in that: The input terminal of the intelligent switch module is electrically connected to a three-phase bus, the output terminal of the intelligent switch module is electrically connected to a user branch, the intelligent switch module is electrically connected to a current detection module, the control module is signal-connected to the intelligent switch module, the output terminal of the current detection module is signal-connected to a signal conditioning module, the signal conditioning module is a signal conditioning circuit, the output terminal of the signal conditioning module is signal-connected to a communication module, and the communication module is bidirectionally signal-connected to a host computer.

2. The load balancing system for an electricity meter box according to claim 1, characterized in that: The output signal of the communication module is connected to the input of the smart meter. The communication module uses LoRa wireless communication and is used to upgrade old distribution cabinets that are difficult to modify.

3. The load balancing system for an electricity meter box according to claim 2, characterized in that: The communication module is bidirectionally connected to the control module, the control module is bidirectionally connected to the heat dissipation module, and the heat dissipation module is signal-connected to the intelligent switch module.

4. The load balancing system for an electricity meter box according to claim 1, characterized in that: The intelligent switch module consists of a three-phase solid-state relay group, each group containing three bidirectional thyristors. The bidirectional thyristors can be replaced with IGBT modules, which are suitable for higher frequency switching scenarios.

5. A load balancing system for an electricity meter box according to claim 4, characterized in that: The input terminals of the three-phase solid-state relay group are connected in parallel to the three-phase bus, and the output terminals are respectively connected to the user branches. The trigger electrode of the bidirectional thyristor is directly connected to the GPIO pin of the main control chip of the control module.

6. The load balancing system for an electricity meter box according to claim 1, characterized in that: The current detection module uses a Hall sensor array and is installed at the input and output terminals of each phase line of the three-phase bus.

7. A load balancing system for an electricity meter box according to claim 6, characterized in that: The Hall sensor is nested in the insulated copper busbar of the three-phase busbar and is used to collect the incoming and outgoing current of each phase line in real time.

8. A load balancing system for an electricity meter box according to claim 3, characterized in that: The heat dissipation module includes a temperature sensor, a heat sink, a cooling fan, and a fan drive circuit. The control terminal of the fan drive circuit is electrically connected to the control module, and the output terminal of the fan drive circuit is electrically connected to the cooling fan. The heat sink is attached to the heat dissipation surface of the three-phase solid-state relay group. The temperature sensor is installed close to the heat sink of the three-phase solid-state relay group and is used to monitor the temperature of the heat sink of the three-phase solid-state relay group. The temperature sensor is connected to the control module for signal transmission of heat sink temperature data in real time.

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