Several attempts on unattended transformation of 3

2022-10-19
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Several attempts of unattended transformation of rural 35kV substation

Abstract: there are generally two methods for unattended transformation of rural 35kV conventional substation: one is to replace the original control and protection equipment with microcomputer control and protection equipment. This method has many investments and long power outage time, which affects the reliability of power supply; Second, the transformation is carried out on the basis of the original equipment, and the interface between the AC telecontrol device and the dispatching end is adopted to achieve the purpose of unattended. This method has the advantages of less investment, quick effect, and generally does not affect the power supply, so it is an ideal transformation method

key words: Rural unattended 35kV substation transformation attempts several attempts of rural 35kV substation unattended transformation the control and protection of the original rural 35kV conventional substation is mostly electromagnetic relay system, with complex wiring and poor accuracy, which relatively restricts the development of power enterprises. The substation is unattended and has the functions of telemetry, remote signaling, remote control and remote adjustment. It is an important means to promote technological progress, strengthen modern electric management, improve electric automation level, and realize personnel reduction and efficiency increase. It is also an urgent requirement to improve the quality and reliability of power supply and ensure safe and economic operation. There are generally two methods for unattended transformation of rural 35kV conventional substation: one is to replace all the original control and protection equipment with microcomputer control and protection equipment. This method has many investments and long power outage time, which affects the reliability of power supply; Second, the transformation is carried out on the basis of the original equipment, and the interface between the AC telecontrol device and the dispatching end is adopted to achieve the purpose of unattended. This method has the advantages of less investment, quick effect, and generally does not affect the power supply, so it is an ideal transformation method. According to the specific reality, the methods adopted by our bureau in the unattended transformation of the substation are: (1) the accessories of FJ Jinan new era Gold Testing Instrument Co., Ltd. are divided into compression accessories, tensile strength test accessories (Brazil splitting method), variable angle shear accessories y-1-004 telemetry power board to realize the telemetry of the substation: telemetry, and these "three confidence" require us to support the identification of core values, including 35kV and 10kV bus voltage The six advantages of open delta voltage, used electric voltage and main transformer make nylon material a new trend of oil pan and the current, active power and reactive power of each outgoing line. The above quantities are sent to the RTU through the AC sampling layer to realize the remote real-time monitoring of the substation operation data by the dispatching end, which provides a basis for timely mastering the substation load, reasonably adjusting the operation mode, realizing economic dispatching, reading and reporting electricity at a fixed point, and analyzing and calculating the comprehensive line loss. Each fjy-1-004 telemetry function board is externally connected with two AC sampling layers, and each AC sampling layer can be connected with six channels of telemetry. Each substation can determine the number of blocks according to the number of telemetry, so as to realize the telemetry of all electrical quantities of the substation. The telemetering of DC electrical quantity and temperature can be realized by DC transmitter and temperature transmitter. (2) Using fjy-1-006 function board to realize remote signaling function: in order to realize the acquisition of signal switching value, it is necessary to partially transform the original signal circuit. Replace the original dx-11 electromagnetic relay with jx-11 static signal relay to realize the expansion of signal contacts and the remote reset of lost cards, change the original optical card circuit to the newly added intermediate relay, start the optical card by a pair of contacts of the intermediate relay, and connect the other docking point to RTU and send signals to the dispatching terminal. In addition, the normally closed contact of the relay at the closing position and the relay at the tripping position are used to connect the normally closed contact of the reducer of Jinan assaying machine in series, and the RTU sends the "control circuit disconnection" signal to the dispatching end, changing the original "lost card not reset" optical plate to an intermediate relay, and using its two pairs of contacts to send the "lost card not reset" signal and connect the accident bus to the RTU respectively. Once a fault trip occurs and the switch position changes, an accident signal will be sent to the dispatching end. At the same time, a pressure plate LP is connected in series in the signal circuit, and it is disconnected during the normal maintenance and commissioning of the switch to prevent the wrong signal to the RTU. Take the signal circuit after the transformation of the transformer (Figure 1) as an example: (3) use fjy-1 remote control board to realize the remote control function of the substation: the dispatching end sends the opening and closing instructions to the RTU through the CPU, and the RTU starts the opening intermediate relay (FZJ) and closing intermediate relay (hzj) on the remote control board. The opening and closing intermediate relay starts, and uses its contact to connect the opening and closing control circuit to realize the remote opening and closing operation of the switch. (as shown in figures 2 and 3) similarly, use the normally open contact of the remote control execution relay zj1 to connect the signal relay to reset the voltage coil circuit, and use the normally open contacts of the remote control execution relays zj2 and ZJ3 connected in parallel on the warning signal release button and the accident signal release button to remotely reset the warning signal and accident signal sound. (as shown in Figures 4 and 5) Several attempts on unattended transformation of 35kV substation in the hottest countryside