CN104502881A - Device for eliminating and monitoring PT (Potential Transformer) secondary circuit voltage drop - Google Patents

Abstract

The invention discloses a PT secondary circuit voltage drop elimination and monitoring device, including a voltage follower module circuit, a power supply module, a detection module, a CPU module and a switching module circuit, and the detection module performs real-time sampling detection on the input and output terminals of the voltage follower module , the CPU module monitors the working condition of the voltage follower module by sampling, comparing and analyzing the received power data, and determines the switching between the voltage follower module and the external resistance module; the voltage follower module circuit is packaged as the first unit; the power module, detection The module, the CPU module, and the switching module circuit are packaged as a second unit; the first unit and the second unit are movably connected through plug-in terminals; the outer surface of the first unit is provided with conductive contacts, and the second unit The paired conductive contacts are provided; some of the contacts are used for the electrical connection of the voltage follower module circuit and the switching module, and some of the contacts are used for the electrical connection of the voltage follower module circuit and the power module.

Description

A PT secondary circuit pressure drop elimination and monitoring device

technical field

The invention relates to the field of power systems, in particular to a PT secondary circuit voltage drop elimination and monitoring device in the power industry based on the principle of a voltage follower.

Background technique

DL/T448-2000 "Management Regulations for Electric Energy Metering Management Technology" stipulates the allowable range of voltage drop in the PT secondary circuit of various electric energy metering devices. The domestically produced PT secondary circuit voltage drop elimination devices based on the voltage follower principle all adopt an integrated product structure, and there are the following problems in actual work:

(1) Follower circuit components need to be replaced and repaired in time when the circuit components are damaged or cannot meet the working performance requirements due to self-heating, inadequate ventilation and heat dissipation, sudden changes in external voltage, inrush current, etc. The device with integrated structure needs to be replaced as a whole. The work required removal of the old unit and installation of a new unit in the PT secondary circuit.

(2) Overall replacement of the device: Before the replacement work, it is necessary to apply for permission from the relevant department. After the replacement, it is necessary to make up for the power loss due to the power outage of the PT secondary circuit during the replacement work. The procedure is cumbersome, and the power is incomplete.

(3) Most of the existing devices lack the function of monitoring the PT secondary circuit working conditions (voltage, current, power, power factor), and the operation and management of the devices are inconvenient.

Contents of the invention

Purpose of the invention: The technical problem to be solved by the present invention is to provide a PT secondary circuit pressure drop elimination and monitoring device for the deficiencies of the prior art.

In order to solve the above technical problems, the present invention discloses a PT secondary circuit voltage drop elimination and monitoring device, a voltage follower module circuit, a power module, a detection module, a CPU module and a switching module circuit,

The detection module performs real-time sampling detection on the input and output terminals of the voltage follower module, collects power data and transmits it to the CPU module for processing;

The CPU module monitors the working conditions of the voltage follower module by sampling, comparing and analyzing the received power data, and determines the switching between the voltage follower module and the external resistance module;

The voltage follower module circuit is packaged as a first unit; the power supply module, detection module, CPU module and switching module circuit are packaged as a second unit;

a removable movable connection between the first unit and the second unit;

The outer surface of the first unit is provided with more than three terminal conductive contacts, and the second unit is provided with more than three terminal conductive contacts; some (more than two) terminal conductive contacts are used for voltage followers The electrical connection between the module circuit and the switching module, and the remaining (more than two) terminal conductive contacts are used for the electrical connection between the voltage follower module circuit and the power module; for example, an optional technical solution of the present invention, the first unit outside 16 terminal conductive contacts are provided on the surface, and the second unit is provided with 16 terminal conductive contacts paired with it; 8 terminal contacts are used for electrical connection between the voltage follower module circuit and the switching module, and 6 terminal contacts The contacts are used for electrical connection between the voltage follower module circuit and the power module;

The switching module circuit is used to control the electrical connection or disconnection between the first unit and the second unit according to the instructions of the CPU.

In the present invention, the first unit includes a first heat dissipation module, the second unit includes a second heat dissipation module, and the first unit and the second unit are provided with two terminal contacts for the first heat dissipation module and the second heat dissipation module. unit connection.

In the present invention, the second unit includes a display module connected to the CPU module.

In the present invention, the second module includes a communication module connected with the CPU module.

In the present invention, the first unit and the second unit are detachably connected through a plug-in connection terminal.

Compared with existing devices, the inventive method has the following advantages

1. Because the voltage follower module and its heat dissipation module are used to form the first unit as an independent structure, the first unit and the second unit are connected by plugging in and out through terminals. When the first unit is replaced, the second unit switches the module to make the metering The device returns to the working state of the original PT secondary circuit, and the maintenance and replacement work has no effect on the normal measurement. The maintenance and replacement work becomes very convenient, saving the maintenance cost of the user and the manufacturer.

2. Because the independent structure of the first unit is formed by the voltage follower module and its heat dissipation module, the first unit and the second unit are connected by plugging in and out through terminals. When the load power of the secondary circuit changes within a certain range, replace it Follower modules with different powers can meet the demand of load power changes. The problem can be solved by replacing the first unit on site, and the second unit does not need to be changed, which saves the transformation cost.

3. The circuits of the first unit and the second unit are disconnected from the switching module through the switch, and the on-site plug-in and replacement of the first unit is a non-electric operation, which improves the safety of maintenance personnel.

4. Because the real-time sampling of the output current is added, the real-time monitoring of the PT secondary circuit working condition is realized, and an effective means for managing the operation of the PT secondary circuit is provided.

Description of drawings

The advantages of the above and/or other aspects of the present invention will become clearer as the present invention will be further described in detail in conjunction with the accompanying drawings and specific embodiments.

Figure 1 is a schematic diagram of the overall structure of Embodiment 1.

FIG. 2 is a schematic diagram of the external packaging structure of Embodiment 1.

Detailed ways

Example 1

As shown in Figure 1, in this embodiment, the voltage follower module circuit and the follower cooling module circuit are formed into an independent whole 1, that is, the first unit, and other modules of the device such as a power supply module, a detection module, a CPU module, a communication module, a display module, The switching module circuit forms an independent whole 2, that is, the second unit. The whole 1 circuit is separated from the whole 2 circuit, and is connected in a plug-in manner through conductive terminals. The outer surface of the whole 1 is provided with 16 terminal conductive contacts, and the said whole 2 is provided with 16 terminal conductive contacts paired with it; among them, 8 terminal contacts are used for the electrical connection of the voltage follower module circuit and the switching module , 6 terminal contacts are used for the electrical connection of the voltage follower module circuit and the power module. The whole 1 includes a first heat dissipation module, and the whole 2 includes a second heat dissipation module. The whole 1 and the whole 2 are provided with two terminal contacts for connecting the first heat dissipation module and the whole 2 .

Wherein, the cooling module inside the whole 1 is connected to the external 220V power supply through the switch inside the whole 2 . The voltage follower module of the whole 1 is connected to the power module and the switching module of the whole 2 respectively. The power modules of the whole 2 are respectively the communication module, the display module, the CPU module, the detection module and the switching module to supply power, and the CPU module is respectively connected to the communication module. The display module, the detection module and the switching module are powered, the communication module is connected to the display module, and the detection module is connected to the switching module. The switching module is connected to the external PT secondary circuit, resistance module and electric energy meter at the same time.

When the detection module detects that the follower is damaged or the performance does not meet the working requirements, the device instantly restores the original PT secondary circuit working state through the overall 2 switching module circuit, and the overall 1 circuit is disconnected from the overall 2 circuit through the switch and switching module circuit or connect.

The voltage follower module and follower heat dissipation module form an independent whole 1, and other modules of the device such as power supply module, detection module, CPU module, communication module, display module, and switching module form an independent whole 2, and the whole 1 and the whole 2 pass through The conductive terminals are connected in a plug-in manner, and the whole 1 is embedded on the surface of the whole 2 . When the detection module detects that the follower is damaged or the performance does not meet the working requirements, the device instantly restores the original PT secondary circuit working state through the whole 2 switching module, and the whole 1 is disconnected from the whole 2 through the switch and the switching module on the circuit. Only the whole body 1 needs to be replaced on the spot. Due to the plug-in connection, maintenance work is very convenient.

The detection module performs real-time sampling and detection on the input and output terminals of the voltage follower module, collects input terminal voltage, output terminal voltage, and current parameters, and processes them by the CPU module. The CPU module monitors the working conditions of the voltage follower module through real-time sampling and comparative analysis of the input and output voltages, and determines the simultaneous switching of the voltage follower module and the resistance module; through real-time sampling of the input terminal voltage (or output terminal voltage) and output terminal current parameters According to the analysis, no matter whether the voltage follower module is in the switching or cutting state, the monitoring of the working condition of the PT secondary circuit can be realized.

The working condition information of the PT secondary circuit is transmitted to the background locally through the device 485/Ethernet, or remotely transmitted to the background through GPRS. Operational management of circuit conditions.

As shown in Figure 2, after packaging in this embodiment, the whole 2 can be set as a structure with grooves, the size of the whole 1 is adapted to the groove of the whole 2, and a cuboid whole is formed after installation, the structure is stable, beautiful, and easy to install. Disassemble and replace.

Example 2

This embodiment says the mode of concrete engineering application:

1. Independent whole 1

1. The voltage follower circuit module and heat dissipation module constitute an independent whole1.

2. The independent whole 1 is connected with the independent whole 2 by plugging and unplugging

3. The working power of the independent whole 1 is provided by the independent whole 2

Two, independent whole 2

1. The working power module, CPU module, switching module, detection module, heat dissipation module and communication module constitute an independent whole2

2. The independent whole 2 is connected to the PT secondary circuit in series near the end of the electric energy meter

3. Independent overall 2 output signal control in the PT outlet terminal box and connected in parallel to the resistance module of the PT secondary circuit and the voltage follower to switch synchronously

3. Accessories

Installation accessory hangers (2 pcs), 4mm ² wires (four colors 4x5), Phoenix voltage terminals (2 groups), pin-type (cold-pressed) wire ends (26 pcs), bar racks (2 pcs), data connection wires (2 root), power line (1), signal line 2.5mm ² several lengths

The present invention provides a PT secondary circuit pressure drop elimination and monitoring device. There are many methods and approaches for realizing the technical solution. The above description is only a preferred embodiment of the present invention. As far as people are concerned, some improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention. All components that are not specified in this embodiment can be realized by existing technologies.

Claims (5)

1. A PT secondary circuit voltage drop elimination and monitoring device, including a voltage follower module circuit, a power module, a detection module, a CPU module and a switching module circuit, The detection module performs real-time sampling detection on the input and output terminals of the voltage follower module, collects power data and transmits it to the CPU module for processing; The CPU module monitors the working conditions of the voltage follower module by sampling, comparing and analyzing the received power data, and determines the switching between the voltage follower module and the external resistance module; It is characterized in that the voltage follower module circuit is packaged as a first unit; the power supply module, detection module, CPU module and switching module circuit are packaged as a second unit; a removable movable connection between the first unit and the second unit; The outer surface of the first unit is provided with more than three terminal conductive contacts, and the second unit is provided with more than three terminal conductive contacts; some of the terminal conductive contacts are used for voltage follower module circuits and switching The electrical connection of the module, and the other terminal conductive contacts are used for the electrical connection of the voltage follower module circuit and the power module; The switching module circuit is used to control the electrical connection or disconnection between the first unit and the second unit according to the instructions of the CPU. 2. A PT secondary circuit pressure drop elimination and monitoring device according to claim 1, wherein the first unit includes a first heat dissipation module, the second unit includes a second heat dissipation module, and the first The unit and the second unit are provided with two terminal contacts for connecting the first heat dissipation module and the second unit. 3 . The device for eliminating and monitoring pressure drop in a PT secondary circuit according to claim 1 , wherein the second unit includes a display module connected to a CPU module. 4 . 4. A PT secondary circuit pressure drop elimination and monitoring device according to claim 1, wherein the second unit includes a communication module connected to the CPU module. 5. A PT secondary circuit pressure drop elimination and monitoring device according to claim 1, characterized in that the first unit and the second unit are detachably connected through plug-in terminals.