“Smart Transformers Simplify Our Work.”

How important is maintenance to you?

Very impor­tant! A trans­former is a bit like a human being. Most of us go to the doc­tor once every year to check that every­thing is as it should be. If this isn’t the case, then the doc­tor takes the nec­es­sary steps. We do the exact same thing when we dis­cov­er from the trans­former data that some­thing isn’t right. This is how we start to look for and rec­ti­fy a prob­lem. To do this, we have to mon­i­tor the trans­form­ers.

How does this monitoring work?

Today, this main­ly hap­pens in two ways: We receive some data via a SCADA con­trol sys­tem; for oth­er data, col­leagues must go to the trans­form­ers and read off the infor­ma­tion direct­ly. These val­ues pro­vide infor­ma­tion on the for­ma­tion of gas­es in oil or the max­i­mum heat which may be applied to the wind­ings, for exam­ple.

”The grad­ual dig­i­tal­iza­tion of our trans­form­ers means that we receive a lot more infor­ma­tion — and in real time to boot!”

For this tra­di­tion­al main­te­nance method, we are cur­rent­ly work­ing with pre­dom­i­nant­ly time-based or pre­ven­ta­tive main­te­nance – just like a per­son going to the doc­tor reg­u­lar­ly. It goes with­out say­ing that this is very time-con­sum­ing and we have to car­ry out a lot of ser­vice calls on site to make this type of main­te­nance pos­si­ble. But this will change in the future.

In what way?

The grad­ual dig­i­tal­iza­tion of our trans­form­ers means that we receive a lot more infor­ma­tion – and in real time to boot! We are there­fore able to eval­u­ate the sta­tus of our sys­tems sig­nif­i­cant­ly more quick­ly, more effi­cient­ly, and above all more con­sis­tent­ly than before. A con­crete exam­ple of this is seen in our two newest trans­form­ers which will help us to make our grid more reli­able. These two mod­els con­tin­u­al­ly pro­vide us with infor­ma­tion on their “state of health” and we can there­fore act on the basis of this data.

Which values can they record?

They can inform us of the tem­per­a­tures at var­i­ous points on the trans­former, for exam­ple – whether this is on the low­er part, the upper part or in the pri­ma­ry or sec­ondary wind­ing. We can also mon­i­tor the for­ma­tion of hydro­gen, car­bon monox­ide, and humid­i­ty with­out fal­si­fi­ca­tion and thus con­tin­u­al­ly deter­mine the qual­i­ty of the oil. Fur­ther­more, we receive infor­ma­tion via the on-load tap-chang­er about the cur­rent load, volt­age, amper­age, and the posi­tion of the tap-chang­er. Thanks to the bush­ing mon­i­tor­ing MSense BM, we are also able to con­tin­u­al­ly mon­i­tor the trans­former bush­ings online for the first time.

How do you benefit from monitoring the transformers in real time?

The smart trans­form­ers sim­pli­fy our work con­sid­er­ably and help us to cut costs. Since we receive all infor­ma­tion in our con­trol cen­ters around the clock and in real time, we are able to react much more quick­ly and with more pre­ci­sion to pos­si­ble prob­lems. This takes us from pre­ven­ta­tive main­te­nance to con­di­tion-based main­te­nance, which means that we act exact­ly when required – nei­ther too ear­ly nor too late. Apart from this, we now no longer need to trav­el to the trans­form­ers to get infor­ma­tion. Instead, we can access them direct­ly from the con­trol cen­ter. Few­er ser­vice calls and the ear­ly detec­tion of prob­lems enable us to sig­nif­i­cant­ly reduce our costs over the ser­vice life of the trans­former. This demon­strates that our invest­ments in new tech­nol­o­gy are def­i­nite­ly pay­ing off.

Which features do you think are the most beneficial?

I would like to point out two things here: The oil-analy­sis sys­tem and the bush­ing mon­i­tor­ing. Using the oil analy­sis, we can con­ve­nient­ly mon­i­tor the oil qual­i­ty and detect poten­tial prob­lems ear­ly on. We are there­fore able to min­i­mize the risk of one of our trans­form­ers becom­ing inop­er­a­tive. And the bush­ing mon­i­tor­ing from Rein­hausen cer­tain­ly rep­re­sents our great­est break­through. Pre­vi­ous­ly, we weren’t able to mon­i­tor this impor­tant part of the trans­former at all. Now we receive infor­ma­tion in real time about the aging of the bush­ings, the humid­i­ty, and their gen­er­al “state of health”.

You are a pilot customer of Reinhausen for the bushing monitoring. Did you need to spend a long time considering this offer?

Not at all – since we have been suc­cess­ful­ly col­lab­o­rat­ing with Rein­hausen for decades. Almost all of our trans­form­ers have an on-load tap-chang­er from this com­pa­ny. The old­est dates back to the year 1974 and still works per­fect­ly. We there­fore had no doubt that Rein­hausen would pro­vide a high-qual­i­ty and tech­ni­cal­ly sophis­ti­cat­ed sys­tem which would be of real ben­e­fit for us. This is the advan­tage of such a long part­ner­ship: That you know exact­ly what you’re get­ting and that you can rely on the oth­er par­ty.

What are your plans for the future of your transformer fleet?

A total of 23 trans­form­ers are work­ing in our grid. Just under half of these are between 31 and 50 years old. As a result of the increas­ing ener­gy demand, we will soon be unable to meet the required redun­dan­cy cri­te­ria with some of our sub­sta­tions. We will there­fore grad­u­al­ly replace these old­er trans­form­ers with new­er ones which will pre­pare us for future load require­ments as well as advance the dig­i­tal­iza­tion of our fleet.

”We now no longer need to trav­el to the trans­form­ers; we can access them direct­ly from the con­trol cen­ter instead.”

This will cre­ate many addi­tion­al options for improved main­te­nance and reli­a­bil­i­ty as well as reduce costs across the over­all ser­vice life of the sys­tems – I think this is very clear­ly the way for­ward. As soon as we have dig­i­tal­ized a suf­fi­cient num­ber of trans­form­ers, we would then also like to intro­duce a TESSA fleet man­age­ment sys­tem in order to mon­i­tor our entire grid even more effi­cient­ly.