CN203707759U - TV parallel circuit preventing reverse charging - Google Patents

Abstract

The utility model discloses an anti-reverse charging TV parallel circuit, comprising a programmable controller PLC, and a 220/24V DC/DC power supply module connected to the power supply end of the programmable controller PLC; the Y0 of the programmable controller PLC - Y2 terminal is connected to the voltage of each phase of the TV protection winding of I bus and II bus in turn, Y3-Y5 is connected in turn by the I bus and II bus TV metering winding voltage, and Y6 terminal is connected to the I bus and II bus open triangle voltage ; The PLC analog input terminals AD0, AD1, and AD2 of the programmable controller are respectively connected through the voltage acquisition conversion module; the voltage acquisition conversion module is composed of the secondary in-phase voltage difference of each phase bus through the voltage conversion module; The new type reduces the operating risk of operators and prevents equipment damage.

Description

An anti-reverse charging TV parallel circuit

technical field

The utility model relates to a TV parallel circuit, in particular to an anti-reverse charging TV parallel circuit. the

Background technique

The voltage transformer in the substation is used to measure the voltage of the high-voltage busbar. For the wiring of the busbar section, in order to ensure the secondary voltage and primary correspondence of the protection, metering and other equipment in the station, each section of the busbar is equipped with a voltage transformer (TV ), there is a voltage parallel circuit in the secondary. When a section of busbar TV needs to be overhauled or shut down due to failure, it can continue to provide secondary voltage for this section of busbar equipment through the voltage parallel circuit. brake. However, the traditional parallel loop has the following problems:

1. The parallel condition only judges the switching value, but does not judge whether the analog value (voltage) is normal. As long as the parallel operation is performed once, even if the secondary air switch of the outage TV is not disconnected, the TV can be paralleled twice, resulting in a reverse charging accident. . the

2. Before paralleling, when any TV high-voltage fuse blows or fails, causing voltage abnormality, if the TV is forced to be paralleled without returning the fault, TV reverse charging will occur, causing the voltage circuit breaker to trip or even burn the TV. the

3. When the I bus and II bus are running in parallel, if the TV high voltage fuse is blown during the operation, the second time cannot be automatically disconnected, and the same consequences will occur. the

The recoil power is transmitted from the secondary side of the transformer to the primary busbar. Once this happens, it will cause overcurrent damage to the voltage TV parallel device, tripping of the circuit breaker, and even cause malfunction of protection equipment, tripping of the circuit breaker, and damage to the transformer. and other serious consequences. In the process of on-site switching operation and maintenance, TV parallel reverse charging accidents often occur due to personnel misoperation or equipment failure. the

The existing TV secondary voltage parallel devices are all simple relay control devices, which cannot effectively prevent the occurrence of reverse charging accidents by only relying on the circuit breaker to trip and intercept the current for overload protection. the

Contents of the invention

In view of the above problems, the technical problem to be solved by the utility model is to provide an anti-reverse charging TV parallel circuit. the

The anti-reverse charging TV parallel circuit of the utility model includes a programmable controller PLC, and a 220/24V DC/DC power supply module connected to the power supply end of the programmable controller PLC; Y0-Y2 terminals of the programmable controller PLC The voltage of each phase of the TV protection winding of the I bus and the II bus is connected in turn, the Y3-Y5 terminal is connected in turn by the I bus and the II bus TV metering winding voltage, and the Y6 terminal is connected by the I bus and the II bus open triangle voltage; the said The programmable controller PLC analog input terminals AD0, AD1, and AD2 are respectively connected through the voltage acquisition and conversion module; the voltage acquisition and conversion module is composed of the secondary in-phase voltage difference of each phase bus through the voltage conversion module; the programmable control The IN0 terminal of the PLC is connected in series by the 1DL relay terminal and the 1G and 2G positions of the bus tie circuit breaker isolation switch, and the IN1 terminal is connected in parallel with the QK handle of the existing TV parallel device; Y0-Y6 of the programmable controller PLC Both terminals are connected to a self-recovery circuit with a self-recovery fuse PPTC as the core. the

Further, the Y7 terminal of the programmable controller PLC is connected through a switch. the

Further, terminals Y8 and Y9 of the programmable controller PLC are respectively connected to a green LED (not shown) and a red LED (not shown). the

Beneficial effects of the utility model: the utility model proceeds from the improvement of the parallel principle, increases the analog quantity (voltage) criterion, and connects a self-recovery circuit in series in the parallel circuit, which can quickly block the circuit when a fault occurs, and the circuit resumes when the fault is eliminated. It can restore conduction, fundamentally eliminate the occurrence of reverse charging, reduce the operating risk of operators, and prevent equipment damage caused by reverse charging, thereby greatly improving the safety and stability of the primary and secondary equipment in the station, and the installation is simple, The transformation cost is low and will bring huge safety and economic benefits. the

Description of drawings

For ease of illustration, the utility model is described in detail by the following specific implementation and accompanying drawings. the

Fig. 1 is the overall structural diagram of the anti-reverse charging TV parallel circuit of the utility model;

Fig. 2 is a structural diagram of the anti-reverse charging TV parallel circuit voltage acquisition and transformation module of the utility model. the

1-Programmable controller PLC; 2-220/24V DC/DC power supply module; 3-Voltage acquisition conversion module; 4-Self-recovery circuit. the

Detailed ways

As shown in Figure 1 and Figure 2, the anti-reverse charging TV parallel circuit of the present invention includes a programmable controller PLC1, and a 220/24V DC/DC power supply module 2 connected to the power supply end of the programmable controller PLC1; The Y0-Y2 terminals of the programmable controller PLC1 are connected to the voltage of each phase of the TV protection winding of the I bus and the II bus in turn, and the Y3-Y5 terminals are connected in turn by the I bus and the II bus of the TV metering winding voltage, and Y6 is connected to the I bus and the II bus. The triangular voltage of the female opening is connected; the analog input terminals AD0, AD1 and AD2 of the programmable controller PLC1 are respectively connected through the voltage acquisition and transformation module 3; After the voltage conversion module is formed; the IN0 terminal of the programmable controller PLC1 is connected in series by 1DL and the bus tie circuit breaker isolation switch 1G, 2G positions, and IN1 is connected in parallel with the QK handle of the existing TV parallel device; The terminals Y0-Y6 of the programming controller PLC1 are all connected to a self-recovery circuit 4 with a self-recovery fuse PPTC as the core. the

Wherein, the Y7 end of the programmable controller PLC1 is connected through a switch to send out a signal for parallel success; Y8 and Y9 of the programmable controller PLC1 are respectively connected to a green LED (not shown) and a red LED (not shown). As shown in the figure), the green LED indicator means that paralleling is allowed, and the red LED indicator means that the paralleling is successful. the

The utility model starts from improving the parallel principle, increases the analog quantity (voltage) criterion, and connects a self-recovery circuit in series in the parallel circuit, which can quickly block the circuit when a fault occurs, and the circuit can be restored to conduction when the fault is eliminated. It fundamentally eliminates the occurrence of reverse charging, reduces the operation risk of operators, and prevents equipment damage caused by reverse charging, thereby greatly improving the safety and stability of primary and secondary equipment in the station. It is also simple to install and low in renovation costs. Bring huge safety and economic benefits. the

The above-mentioned embodiments are only descriptions of preferred implementations of the present utility model, and are not intended to limit the concept and scope of the present utility model. Under the premise of not departing from the design concept of the present utility model, various modifications and improvements made by ordinary persons in the art to the technical solution of the present utility model should fall into the protection scope of the present utility model, and the technology claimed by the utility model The contents are all described in the claims. the

Claims (3)

1. An anti-reverse charging TV parallel circuit is characterized in that: it comprises a programmable controller PLC (1), and a 220/24V DC/DC power supply module (2) connected to the power supply terminal of the programmable controller PLC (1) The Y0-Y2 ends of the programmable controller PLC (1) are connected by the respective phase voltages of the I mother and II mother TV protection windings successively, and the Y3-Y5 ends are connected by the I mother and II mother TV metering winding voltages successively, Y6 end is connected by I female and II female opening triangle voltage; Described programmable logic controller PLC (1) analog quantity input terminal AD0, AD1, AD2 are inserted through voltage acquisition conversion module (3) respectively; Described voltage acquisition conversion The module (3) is composed of the secondary in-phase voltage difference of each phase bus through the voltage conversion module; the IN0 terminal of the programmable controller PLC (1) is connected in series with the 1DL relay terminal and the bus tie circuit breaker isolation switch 1G and 2G In, the IN1 terminal is connected from the parallel QK handle of the existing TV parallel device; the Y0-Y6 terminals of the programmable controller PLC (1) are all connected to a self-recovery circuit (4) with a self-recovery fuse PPTC as the core . the 2. The anti-reverse charging TV parallel circuit according to claim 1, characterized in that: the terminal Y7 of the programmable controller PLC (1) is connected through a switch. the 3. The anti-reverse charging TV parallel circuit according to claim 1, characterized in that: terminals Y8 and Y9 of the programmable controller PLC (1) are respectively connected to green LEDs and red LEDs. the