Discussion on problems of potentiostat in impressed current cathodic protection system
Potentiostat was the core of impressed current cathodic protection system.Once a fault occurred,it would directly affect the effectiveness of pipeline cathodic protection.Some problems existing in the operation of potentiostat were introduced and several improvement measures were proposed.When the potentiostat was turned off,natural potential of the pipeline was either negative or positive;When the auxiliary anode ground bed was shared,potential fluctuation amplitude of the pipeline increased due to strong mutual interference of different circuits of potentiostat.Under geomagnetic interference,the cathodic protection of pipelines under two different operating modes of constant current and constant potential was compared.The results showed that the effect of cathodic protection was better under constant potential mode.For the interference environment of subway DC stray current,the required current varied at different time periods.It was recommended to use a potentiostat that can preset different operating modes and parameters.The potentiostat can automatically switch to the operating mode according to the set time;oper-ate in the mode of high current constant current during subway operation time,while run in the mode of low current constant po-tential during subway shutdown time.The potentiostat can not only suppress the interference of DC stray current by high current output during subway operation,but also jump to low current output during subway shutdown to prevent pipeline over protection.
potentiostatshared auxiliary anode ground bedgeomagnetic interferenceinterference of subway DC stray currentconstant potentialconstant current
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维普
