Regulated voltage that saves lives

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In inten­sive care units, ven­ti­la­tors keep patients alive; in oper­at­ing rooms, mon­i­tors keep an eye on their heart rhythms and sound the alarm if some­thing is wrong; and on the wards, infu­sion pumps sup­ply seri­ous­ly ill patients with vital med­ica­tion. These devices must run smooth­ly around the clock and each relies on a con­stant, clean, and sta­ble sup­ply of pow­er. When that sup­ply fal­ters, the con­se­quences can be cat­a­stroph­ic. There­fore, if the pow­er fails in a hos­pi­tal, every sec­ond counts–because even the emer­gency pow­er reserve is lim­it­ed.

But it doesn’t always have to be a pow­er fail­ure; even small volt­age fluc­tu­a­tions can dis­rupt the sen­si­tive elec­tron­ics of life-sup­port tech­nol­o­gy. At the Roy­al Old­ham Hos­pi­tal, recur­ring volt­age fluc­tu­a­tions threat­ened to dis­rupt the hospital’s sen­si­tive process­es. With approx­i­mate­ly 500 beds and more than 3,500 employ­ees, the hos­pi­tal is one of the larg­er clin­ics in Greater Man­ches­ter and offers patients com­pre­hen­sive inpa­tient and out­pa­tient care.

A failure must be prevented at all costs

The Roy­al Old­ham Hos­pi­tal oper­ates like a self-con­tained town with its own com­plex elec­tri­cal net­work. Mul­ti­ple trans­form­ers step down the grid sup­ply volt­age for var­i­ous oper­a­tional zones, while a gas tur­bine pro­vides sup­ple­men­tary on-site gen­er­a­tion for heat and pow­er effi­cien­cy. This is cor­re­spond­ing­ly com­plex and must also be designed redun­dant­ly in order to reli­ably sup­ply oper­at­ing rooms, inten­sive care units, admin­is­tra­tion, and IT sys­tems with pow­er.

How­ev­er, there had been fre­quent prob­lems in the past with syn­chro­niz­ing the gas tur­bine with the incom­ing grid sup­ply. Repeat­ed issues led to neg­a­tive sequence cur­rents, volt­age insta­bil­i­ty, and harmonics–degrading tur­bine per­for­mance and trig­ger­ing repeat­ed shut­downs of the com­bined heat and pow­er (CHP) plant. In a 24/7 health­care facil­i­ty, such events are unac­cept­able. A quick solu­tion was there­fore need­ed.

A precision solution for a critical network

Recog­nis­ing the com­plex­i­ty of the issue, the region­al dis­tri­b­u­tion net­work oper­a­tor SP Ener­gy Net­works (ENW), rec­om­mend­ed John­son & Phillips, a spe­cial­ist provider of high- and low-volt­age tech­nol­o­gy, to take on the chal­lenge. The com­pa­ny spe­cial­izes in crit­i­cal indus­tries where pro­longed oper­a­tional down­time is unac­cept­able under any cir­cum­stances. The hos­pi­tal project was led by tech­ni­cal direc­tor Neil Probert, and he still remem­bers the start of the project well: “Our first step was a detailed analy­sis of the hospital’s elec­tri­cal infra­struc­ture. We mod­elled the sys­tem behav­ior and designed a solu­tion to erad­i­cate volt­age ari­a­tion and har­mon­ic dis­tor­tion.”

At the cen­ter of this solu­tion is a trans­former fitted with MR’s ECOTAP^® VPD^®, fea­tur­ing a nine-posi­tion auto­mat­ic con­trol range. Thanks to proven vac­u­um tech­nol­o­gy, the tap chang­er is main­te­nance-free and there­fore very reliable–ideal for sen­si­tive grid appli­ca­tions such as hos­pi­tals. “The trans­former equipped with the ECOTAP^® VPD^® now forms the main pow­er sys­tem for crit­i­cal sup­ply areas in the hos­pi­tal,” says Probert. Work­ing in col­lab­o­ra­tion with MR spe­cial­ists, John­son & Phillips adjust­ed the con­trol para­me­ters of the com­pact on-load tap-chang­er to sta­bi­lize volt­age while main­tain­ing syn­chro­ni­sa­tion between the tur­bine and grid.

To com­ple­ment this, two active har­mon­ic filters were installed–one at the turbine’s low-volt­age gen­er­a­tor out­put, and anoth­er at the low-volt­age grid interface–effectively mit­i­gat­ing elec­tri­cal dis­tur­bances and ensur­ing uni­form pow­er qual­i­ty through­out the hos­pi­tal. “We have been work­ing with Maschi­nen­fab­rik Rein­hausen for many years,” says Probert. “Their ECOTAP^® tech­nol­o­gy con­sis­tent­ly deliv­ers out­stand­ing results in our pow­er qual­i­ty and volt­age reg­u­la­tion projects across the UK and inter­na­tion­al­ly. The tech­ni­cal sup­port pro­vid­ed by the MR team was exem­plary.”

Energy you can count on

The John­son & Phillips team exe­cut­ed the instal­la­tion with metic­u­lous plan­ning to avoid dis­rup­tion to hos­pi­tal oper­a­tions. Post-instal­la­tion mea­sure­ments confirmed a sub­stan­tial and sus­tained improve­ment in volt­age sta­bil­i­ty and over­all pow­er qual­i­ty. “This project was our first col­lab­o­ra­tion with SP Ener­gy Net­works and a sig­nifi­cant oppor­tu­ni­ty to show­case our exper­tise in a high­ly sen­si­tive health­care envi­ron­ment,” con­cludes Probert. “We are proud that our solu­tion has deliv­ered the sta­bil­i­ty The Roy­al Old­ham Hos­pi­tal needs–ensuring pow­er con­ti­nu­ity and patient safe­ty around the clock.”