33kv substation operation maintenance

[jaseela123d]

In APCPDCL most substations are designed for two power transformers, two 33KV input sources (one regular and one alternative) and will feed six to eight 11KV feeders. Generally, substations will be fed from one source. In this condition all feeders, station transformer, potential transformer, auxiliary equipment are fed from one source. But when the substation feeds from two different sources of 33 KV at a time due to some technical reasons, then one power transformer will be powered from one source and another power transformer will be powered from another source. This is done by opening the bus coupler on 33KV bus and 11KV bus. At 11KV bus separation, the station transformer will be on one side of the bus only. The transformer of the station will be feeding auxiliary, substation lighting, fans etc and substation lighting and fans will indicate the presence of the incoming supply in most cases. When the 33KV supply that powers the transformer of the station through the power transformer fails, the operator knows by observing the condition (off) of fans and lights in the control room and takes the necessary measures.


Now the parallel transmission line is first connected with surge arrester to trigger the wave, followed by CVT connected in parallel. The CVT measures the voltage and turns a110V. A.C. For the control panel, at the location of a wave trap is connected to carrier communication at the higher frequencies. A current transformer is connected in series with the line measuring current and current descent in relation to 800: 1 for the control panel. Switching equipment is provided, which is the combination of a circuit breaker having an insulator at each end. A transformer is connected to the main bus via a bus coupler. The main bus has a total capacity of 160 MVA for 33 KV, which is subdivided in two transformer capacities of 80 MVA (40MVA + 40MVA) connected in parallel for 33KV and two other transformer capacity of 80KV (40KV + 40KV) are connected in parallel for the Substation. At both ends of the transformer lightning current transformer and switch gear equipment provided. The transformer lowers the voltage from 220KV to 33KV. The main bus is equipped with switching equipment and a current transformer. This gives way to six feeders that transmit energy to INDRA NAGAR. The main bus is connected to the bus bus or transfer bus via a bus coupler and 11KV is provided with switching equipment. This gives way to feeders who transmit power to Sector-25, BhootNath, MunshiPulia, Ring Road and Sarvoday Nagar. An 11KV / 440V reduction transformer is connected to the control panel to provide power to substation equipment. The capacitor bank is connected to the main 11KV bus. It is provided to improve power factor and voltage profile.