Low-voltage power distribution network feeder monitoring device

Abstract

The utility model discloses a feeder monitoring device for a low-voltage power distribution network. The feeder monitoring device is composed of a communication unit, a power supply module and a monitoring unit. The communication unit is generally installed in a power distribution cabinet, a pole-mounted JP cabinet or a low-voltage cable branch box, serves as a data collection gateway to achieve uplink communication through a carrier module, communicates with a downlink monitoring unit through a CAN bus and achieves local maintenance of the system through a Bluetooth interface, and the number of accessible monitoring units is not less than 64. The power supply module provides a direct current power supply, a CAN bus and sampling voltage for the monitoring units through the cascade interface, and a single power supply module can be connected to not less than 10 monitoring units; the monitoring unit is connected with an external current transformer to realize a current detection function, is connected with a voltage sampling signal output by a power supply module to complete a voltage detection function, is connected with switching value input to realize in-station state monitoring, and has the functions of topological characteristic signal emission, characteristic signal analysis, phase sequence identification and the like.

Description

Technical Field

[0001] This utility model relates to the field of power grid operation monitoring technology, specifically a low-voltage distribution network feeder monitoring device. Background Technology

[0002] Currently, under the new grid system, the State Grid and China Southern Power Grid are implementing interactive demand-side management terminals (interactive demand-side management terminals) for large dedicated transformer users. By deploying demand-side management terminals on large dedicated transformer users and completing intelligent and refined control upgrades, these terminals enable remote monitoring and intelligent control of electrical equipment in high-power-consuming industries across various manufacturing sectors. This allows dedicated transformer users to actively participate in energy management, enabling them to understand and control their own electricity consumption in a timely manner, and effectively improve energy efficiency and energy conservation.

[0003] By connecting key energy-consuming circuits for enterprises, comprehensive energy management and a user-friendly interface are provided, allowing users to understand the entire electricity consumption process, detailed electricity distribution, and load attributes. Based on orderly electricity consumption instructions, during peak electricity consumption periods, users can shut down some temporarily interruptible loads according to their own electricity distribution, achieving minimal or no impact on production order.

[0004] In related technologies, due to the lack of effective monitoring and feedback mechanisms, dedicated transformer users may not be able to fully understand their own electricity consumption, thus failing to actively participate in energy management, resulting in widespread energy waste; some power grid feeder monitoring devices cannot provide effective energy use analysis and optimization suggestions, leaving dedicated transformer users without guidance in energy management, which in turn affects energy use efficiency and leads to poor energy-saving effects. Utility Model Content

[0005] The purpose of this invention is to provide a low-voltage distribution network feeder monitoring device to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a low-voltage distribution network feeder monitoring device, comprising:

[0007] The communication unit, which acts as a data aggregation gateway, enables uplink communication via a carrier module, communicates with the downlink monitoring unit via a CAN bus, and enables local maintenance of the power system via a Bluetooth interface.

[0008] The power module provides DC power, CAN bus and sampling voltage to the monitoring unit through a cascading interface;

[0009] The monitoring unit is connected to a current transformer and a voltage sampling signal output from the power module to complete the voltage detection function. It is also connected to a switch input to realize the status monitoring within the substation.

[0010] The monitoring unit includes a topology feature signal transmission module and a feature signal analysis module. The topology identification of the feature signal transmission is achieved by transistor AQ4 and the first auxiliary circuit of transistor AQ4.

[0011] Furthermore, the first auxiliary circuit includes a rectifier bridge AD4, a MOSFET, an optocoupler, a transistor, a diode, and several resistors and capacitors. Pin 1 of the transistor AQ4 is connected to pin 2 of the transistor AQ3 through a current-limiting resistor. Pin 2 of the transistor AQ4 is connected to pin 3 of the positive output of the rectifier bridge AD4. Pin 3 of the transistor AQ4 is connected to AGND along with resistors AR38 and AR40.

[0012] Furthermore, the power module has a minimum input voltage of AC65V and a maximum input voltage of AC400V.

[0013] Furthermore, the power supply module includes APT1, APT2, and APT3, and the model number of APT1, APT2, and APT3 is ZMPT107-1.

[0014] Furthermore, it also includes a load management branch unit, which includes a main control circuit, a voltage and current sampling circuit, a power supply and control circuit;

[0015] The main control circuit is connected to the voltage and current sampling circuit and the power supply and control circuit.

[0016] The main control circuit includes a real-time clock module, an LCD liquid crystal display module, a Bluetooth communication module, an LED indicator and button interaction module, and a FLASH and EEPROM storage module.

[0017] The voltage and current sampling circuit includes a sampling module and a pulse output module;

[0018] The power supply and control circuit includes an auxiliary power supply module, an LDO module, a 485 communication module, a DI input module, and a DO relay output module.

[0019] Furthermore, the voltage and current sampling circuit is implemented by a sampling chip U1 and a second auxiliary circuit of U1, wherein the model of U1 is RN8302; the second auxiliary circuit is composed of voltage transformers CT1, CT2, CT3 and resistors and capacitors;

[0020] Pins 12-17 of U1 are connected to the corresponding resistors and voltage transformers CT1, CT2, and CT3. Pins 4, 5, and 7-10 of U1 are connected to current sampling resistors.

[0021] Compared with the prior art, the beneficial effects of this utility model are:

[0022] (1) Applying the interactive demand-side management terminal for large dedicated transformer users enables dedicated transformer users to actively participate in energy management, allowing users to understand and grasp their own electricity consumption in a timely manner, effectively improving energy efficiency and saving energy.

[0023] (2) Designing the communication function as an independent communication unit is conducive to forming a unified and standardized communication interface, thereby shielding the differences between various terminal communication interfaces and improving the compatibility and scalability of the power system.

[0024] (3) The monitoring unit has current and voltage detection functions, as well as multiple functions such as substation status monitoring, topology characteristic signal transmission and analysis, and phase sequence identification. It realizes comprehensive monitoring of the current of multiple outgoing circuits of low-voltage feeder cabinets and the status of switches in each circuit, thereby improving the safety and stability of the power system. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the main control circuit of this utility model;

[0026] Figure 2 This is the circuit schematic diagram of the main control circuit of this utility model;

[0027] Figure 3 This is the circuit schematic diagram of the Bluetooth module of this utility model;

[0028] Figure 4 This is the circuit schematic diagram of the HLPC of this utility model;

[0029] Figure 5 This is the circuit schematic diagram of the FLSSH of this utility model;

[0030] Figure 6 This is the circuit schematic diagram of the EEPROM of this utility model;

[0031] Figure 7 This is the circuit schematic diagram of the RTC of this utility model;

[0032] Figure 8 This is a branch circuit diagram of the main control circuit of this utility model;

[0033] Figure 9 This is a circuit diagram of the voltage and current sampling circuit of this utility model;

[0034] Figure 10 This is the circuit schematic diagram of the CAN bus of this utility model;

[0035] Figure 11 This is the circuit schematic diagram of the RS485 of this utility model;

[0036] Figure 12 This is a circuit schematic diagram of the topology transmission of this utility model;

[0037] Figure 13 This is the circuit schematic diagram of the chip used in this utility model. Detailed Implementation

[0038] 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.

[0039] Example:

[0040] Please see Figure 1-13 This utility model provides a technical solution: a low-voltage distribution network feeder monitoring device, including a communication unit. The communication unit is generally installed in a distribution cabinet, pole-mounted JP cabinet or low-voltage cable branch box. The chip of the communication unit is an ARM4 chip. The communication unit acts as a data aggregation gateway to achieve uplink communication through a carrier module, communicate with downlink monitoring units through a CAN bus, and achieve local maintenance of the power system through a Bluetooth interface. The number of monitoring units that can be connected is not less than 64.

[0041] A power module provides DC power, CAN bus and sampling voltage to the monitoring unit through a cascading interface. A single power module can be connected to no less than 10 monitoring units.

[0042] The monitoring unit connects to an external current transformer to achieve current detection, connects to the voltage sampling signal output by the power module to achieve voltage detection, and connects to the switch input to achieve substation status monitoring. It has functions such as topology characteristic signal transmission, characteristic signal parsing, and phase sequence identification.

[0043] The monitoring unit includes a topology feature signal transmission module and a feature signal parsing module. Topology identification of the transmitted feature signals is achieved by a transistor AQ4 and its first auxiliary circuit. The transistor AQ4 is a 7N65L. Figure 12 As shown.

[0044] In this embodiment, if Figure 12 As shown, the first auxiliary circuit includes a rectifier bridge AD4, a MOSFET, an optocoupler, a transistor, a diode, and several resistors and capacitors. Pin 1 of the transistor AQ4 is connected to pin 2 of the transistor AQ3 through a current-limiting resistor. Pin 2 of the transistor AQ4 is connected to pin 3 of the positive output of the rectifier bridge AD4. Pin 3 of the transistor AQ4 is connected to AGND along with resistors AR38 and AR40.

[0045] In this embodiment, the minimum input voltage of the power module is AC65V, and the maximum input voltage of the power module is AC400V.

[0046] In this embodiment, if Figure 13 As shown, the monitoring unit consists of a sampling chip AU7, the model of which is RN7326E.

[0047] In this embodiment, if Figure 9 As shown, the power supply module includes APT1, APT2, and APT3, and the model of APT1, APT2, and APT3 is ZMPT107-1.

[0048] In this embodiment, if Figures 1-11 As shown, it also includes a load management branch unit, which includes a main control circuit, a voltage and current sampling circuit, a power supply and control circuit;

[0049] The main control circuit is connected to the voltage and current sampling circuit and the power supply and control circuit.

[0050] The main control circuit includes a real-time clock module, an LCD liquid crystal display module, a Bluetooth communication module, an LED indicator and button interaction module, and a FLASH and EEPROM storage module.

[0051] The voltage and current sampling circuit includes a sampling module and a pulse output module;

[0052] The power supply and control circuit includes an auxiliary power supply module, an LDO module, a 485 communication module, a DI input module, and a DO relay output module.

[0053] In this embodiment, if Figures 1-11 As shown, the voltage and current sampling circuit is implemented by a sampling chip U1 and a second auxiliary circuit of U1. The model of U1 is RN8302.

[0054] In this embodiment, if Figures 1-11 As shown, the second auxiliary circuit consists of voltage transformers CT1, CT2, and CT3, and resistors and capacitors.

[0055] Pins 12-17 of U1 are connected to the corresponding resistors and voltage transformers CT1, CT2, and CT3. Pins 4, 5, and 7-10 of U1 are connected to current sampling resistors.

[0056] Specifically, in use, it consists of a communication unit, a power supply module, and a monitoring unit to realize low-voltage feeder monitoring; the communication unit is installed in the distribution cabinet and other locations as a data aggregation gateway to realize uplink communication, downlink communication, and local maintenance; the power supply module provides DC power, CAN bus, and sampling voltage to the monitoring unit; the monitoring unit realizes current and voltage detection and substation status monitoring.

[0057] The load management branch unit includes a main control circuit, a voltage and current sampling circuit, and a power supply and control circuit. The main control circuit connects the voltage and current sampling circuit and the power supply and control circuit, and contains multiple modules.

[0058] The monitoring unit detects current through an external current transformer and detects voltage through the voltage sampling signal output by the power module.

[0059] The monitoring unit is connected to switch inputs to realize status monitoring within the substation and has functions such as transmitting topology characteristic signals.

[0060] The main control circuit implements functions such as real-time clock, display, Bluetooth communication, LED indication, button interaction, and data storage through various modules. The voltage and current sampling circuit is responsible for sampling and pulse output. The power supply and control circuit provides power, communication, and control functions.

[0061] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A low-voltage distribution network feeder monitoring device, characterized in that, include: The communication unit, which acts as a data aggregation gateway, enables uplink communication via a carrier module, communicates with the downlink monitoring unit via a CAN bus, and enables local maintenance of the power system via a Bluetooth interface. The power module provides DC power, CAN bus and sampling voltage to the monitoring unit through a cascading interface; The monitoring unit is connected to a current transformer and a voltage sampling signal output from the power module to complete the voltage detection function. It is also connected to a switch input to realize the status monitoring within the substation. The monitoring unit includes a topology feature signal transmission module and a feature signal analysis module. The topology identification of the feature signal transmission is achieved by transistor AQ4 and the first auxiliary circuit of transistor AQ4.

2. The low-voltage distribution network feeder monitoring device according to claim 1, characterized in that: The first auxiliary circuit includes a rectifier bridge AD4, a MOSFET, an optocoupler, a transistor, a diode, and several resistors and capacitors. Pin 1 of transistor AQ4 is connected to pin 2 of transistor AQ3 through a current-limiting resistor. Pin 2 of transistor AQ4 is connected to pin 3 of the positive output of rectifier bridge AD4. Pin 3 of transistor AQ4 is connected to AGND along with resistors AR38 and AR40. The model of transistor AQ4 is 7N65L.

3. The low-voltage distribution network feeder monitoring device according to claim 1, characterized in that: The communication unit uses an ARM4 chip.

4. The low-voltage distribution network feeder monitoring device according to claim 1, characterized in that: The power module has a minimum input voltage of AC65V and a maximum input voltage of AC400V.

5. A low-voltage distribution network feeder monitoring device according to claim 1, characterized in that: The monitoring unit consists of a sampling chip AU7, model number RN7326E.

6. The low-voltage distribution network feeder monitoring device according to claim 1, characterized in that: The power supply module includes APT1, APT2, and APT3, and the model of APT1, APT2, and APT3 is ZMPT107-1.

7. A low-voltage distribution network feeder monitoring device according to any one of claims 1-6, characterized in that: It also includes a load management branch unit, which includes a main control circuit, a voltage and current sampling circuit, a power supply and control circuit; The main control circuit is connected to the voltage and current sampling circuit and the power supply and control circuit; The main control circuit includes a real-time clock module, an LCD liquid crystal display module, a Bluetooth communication module, an LED indicator and button interaction module, and a FLASH and EEPROM storage module. The voltage and current sampling circuit includes a sampling module and a pulse output module; The power supply and control circuit includes an auxiliary power supply module, an LDO module, a 485 communication module, a DI input module, and a DO relay output module.

8. A low-voltage distribution network feeder monitoring device according to claim 7, characterized in that: The voltage and current sampling circuit is implemented by sampling chip U1 and a second auxiliary circuit of U1, wherein U1 is model RN8302.

9. A low-voltage distribution network feeder monitoring device according to claim 8, characterized in that: The second auxiliary circuit consists of voltage transformers CT1, CT2, and CT3, and resistors and capacitors; Pins 12-17 of U1 are connected to the corresponding resistors and voltage transformers CT1, CT2, and CT3. Pins 4, 5, and 7-10 of U1 are connected to current sampling resistors.

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