{"id":12388,"date":"2018-09-25T11:30:57","date_gmt":"2018-09-25T09:30:57","guid":{"rendered":"https:\/\/mag.ebmpapst.com\/en\/?p=12388"},"modified":"2024-03-12T17:55:02","modified_gmt":"2024-03-12T16:55:02","slug":"fans-for-oil-cooled-high-power-transformers-robust-efficient-quiet-and-designed-for-worldwide-use","status":"publish","type":"post","link":"https:\/\/mag.ebmpapst.com\/en\/products\/fans\/fans-for-oil-cooled-high-power-transformers-robust-efficient-quiet-and-designed-for-worldwide-use_12388\/","title":{"rendered":"Fans for oil-cooled high-power trans\u00adformers"},"content":{"rendered":"

Trans\u00adformers generate waste heat when they are in oper\u00ada\u00adtion and oil is the coolant of choice. It trans\u00adfers the heat through convec\u00adtion (or supported by pump systems) to the trans\u00adformer housing, which has cooling fins or radi\u00ada\u00adtors similar to heat exchangers on the outside. Large high-power trans\u00adformers require addi\u00adtional cooling: fans that prevent damage from over\u00adheating despite cooling surfaces that are as compact as possible (Fig. 1). The fans have to satisfy special require\u00adments so they can with\u00adstand harsh outdoor deploy\u00adment condi\u00adtions.<\/p>\n

Fans turn trans\u00adformers into energy savers<\/h2>\n
\"Die

Figure 1: The fans used in the cooling systems of large trans\u00adformers must with\u00adstand harsh condi\u00adtions. Here, robust tech\u00adnology that works reli\u00adably for decades and does not require main\u00adte\u00adnance is in demand.<\/p><\/div><\/div>\n

It isn\u2019t enough for fans to support the required air perfor\u00admance. Prop\u00ader\u00adties such as corro\u00adsion resis\u00adtance even in high humidity, no-main\u00adte\u00adnance oper\u00ada\u00adtion without lubri\u00adca\u00adtion, and reli\u00adable func\u00adtioning over as long a service life as possible are just as impor\u00adtant. And when loads fluc\u00adtuate, it is also bene\u00adfi\u00adcial when the cooling capacity can adjust to actual demand. It does not always make sense to switch off indi\u00advidual fans when the trans\u00adformer is in partial-load oper\u00ada\u00adtion because in this state, uncooled \u201chot spots\u201d can arise on the heat exchanger.<\/p>\n

If the fans are oper\u00adating as effi\u00adciently as possible, over the years, users can save signif\u00adi\u00adcant amounts of money and power, which they can feed into the elec\u00adtricity grid. This results in a posi\u00adtive economic benefit for energy oper\u00ada\u00adtors. If the trans\u00adformers are near or even in resi\u00adden\u00adtial areas, the noise they generate plays a role that should not be under\u00ades\u00adti\u00admated either.<\/p>\n

\"Die

Figure 2: The trans\u00adformer fans satisfy all the require\u00adments for sophis\u00adti\u00adcated large trans\u00adformer cooling and come in sizes ranging from 500 mm to 1,250 mm.<\/p><\/div><\/div>\n

ebm-papst Mulfingen, the motor and fan specialist, has addressed this issue by devel\u00adoping special trans\u00adformer fans (Fig. 2). They satisfy all the require\u00adments for sophis\u00adti\u00adcated large trans\u00adformer cooling as per DIN EN 50216-12 \u201cPower trans\u00adformer and reactor fittings \u2013 Part 12: Fans\u201d and come in sizes 500 mm to 1,250 mm with air perfor\u00admance of up to 13 m\u00b3\/s.<\/p>\n

Their devel\u00adop\u00adment is based on decades of expe\u00adri\u00adence and intense research supported by exten\u00adsive simu\u00adla\u00adtions and tests. They also satisfy special require\u00adments with regard to long service life and salt spray resis\u00adtance (corro\u00adsion protec\u00adtion class C5M as per DIN EN ISO 12944), so the fans are suit\u00adable for deploy\u00adment in coastal areas with high salt contents.<\/p>\n

Fan housing increases fan effi\u00adciency<\/h2>\n
\"Durch

Figure 3: Axial fan instal\u00adla\u00adtion without a fan housing means major airflow losses (left). A fan housing can signif\u00adi\u00adcantly increase air perfor\u00admance in the oper\u00adating range.<\/p><\/div><\/div>\n

All the compo\u00adnents of the plug-&-play-compatible modules \u2013 the fan housing, HyBlade\u00ae impeller, Green\u00adTech EC motor with inte\u00adgrated elec\u00adtronics or AC asyn\u00adchro\u00adnous motor and intake-side guard grille \u2013 are perfectly harmo\u00adnized. For example, aero\u00addy\u00adnamic opti\u00admiza\u00adtion reduces both air turbu\u00adlence and oper\u00adating noise. The two motor types satisfy the require\u00adments of the current ecode\u00adsign direc\u00adtive.<\/p>\n

The impeller has an aero\u00addy\u00adnam\u00adi\u00adcally ideal form based on combining an aluminum frame with a covering of glass-fiber-rein\u00adforced plastic. This reduces the noise it produces dramat\u00adi\u00adcally, enabling higher effi\u00adciency in compar\u00adison to tradi\u00adtional blades. The motor mount, which also has a contact protec\u00adtion func\u00adtion, is installed on the intake side. On the outlet side, a guard grille is also avail\u00adable as an acces\u00adsory.<\/p>\n

\n

If the fans are oper\u00adating as effi\u00adciently as possible, over the years, users can save signif\u00adi\u00adcant amounts of money and power.<\/p>\n<\/blockquote>\n

Both the guard grille and the fan housing are made of hot-dip galva\u00adnized sheet steel with an extra coating. The outlet side also has an inte\u00adgrated circum\u00adfer\u00aden\u00adtial flange for direct attach\u00adment to the radi\u00adator. Espe\u00adcially when the fans func\u00adtion with free air (as usual in the case of oil-cooled trans\u00adformers), the posi\u00adtive effect of this type of fan housing is excel\u00adlent (Fig. 3). It keeps air turbu\u00adlence to a minimum, increasing the airflow rate and there\u00adfore, fan effi\u00adciency (Fig. 4).<\/p>\n

Speed control for needs-based cooling<\/h2>\n
\"Figure<\/a>

Figure 4: Fans with a fan housing deliver higher air perfor\u00admance and higher effi\u00adciency, which leads to signif\u00adi\u00adcantly better system effi\u00adciency (1) in compar\u00adison to fans without a fan housing (2).<\/p><\/div><\/div>\n

Compa\u00adnies that rely on proven Green\u00adTech EC tech\u00adnology are taking one more step in the direc\u00adtion of energy effi\u00adciency. EC motors are basi\u00adcally synchro\u00adnous motors with perma\u00adnent magnet excite\u00adment. In them, a rotor with inte\u00adgrated perma\u00adnent magnets synchro\u00adnously follows the rotating field of the stator, which is gener\u00adated elec\u00adtron\u00adi\u00adcally. The control elec\u00adtronics enable infi\u00adnitely adjustable air perfor\u00admance (linear to the fan speed), which devi\u00adates from the grid-synchro\u00adnous frequency in partial-load oper\u00ada\u00adtion at prac\u00adti\u00adcally the same high level of effi\u00adciency. The open-loop speed control can either be spec\u00adi\u00adfied analog via 0-10 VDE (e.g. oil temper\u00ada\u00adture or oil pres\u00adsure sensor) or digi\u00adtally with a PWM or MODBUS signal. When MODBUS is used, several fans can be conve\u00adniently inter\u00adcon\u00adnected. This facil\u00adi\u00adtates the use of diag\u00adnos\u00adtics and moni\u00adtoring func\u00adtions, which ulti\u00admately contribute to reli\u00adable oper\u00ada\u00adtion. This set up means the entire system can be oper\u00adated more econom\u00adi\u00adcally and has a posi\u00adtive effect on the life cycle costs.<\/p>\n

\n

Compa\u00adnies that rely on proven Green\u00adTech EC tech\u00adnology are taking one more step in the direc\u00adtion of energy effi\u00adciency.<\/p>\n<\/blockquote>\n

To prevent hot spots on the heat exchanger after indi\u00advidual fans have been switched off, ebm-papst recom\u00admends using all fans in partial-load oper\u00ada\u00adtion. The conse\u00adquence is a more even flow through the radi\u00adator. A posi\u00adtive side effect: the motor does not heat up as dramat\u00adi\u00adcally, which extends the fan\u2019s service life. Another aspect of partial-load oper\u00ada\u00adtion is the high reduc\u00adtion in energy consump\u00adtion and oper\u00ada\u00adtion noise as a result of the phys\u00adical laws. The elec\u00adtrical input power is propor\u00adtional to the fan speed to the third power (Pe ~ n\u00b3). As a result, it is only 12.5\u2009\u2009% when the speed and in turn, the air perfor\u00admance, are reduced by 50\u2009\u2009%. Loga\u00adrith\u00admi\u00adcally, this reduces the noise level by 15 dB (Fig. 5).<\/p>\n

\"m\u00f6gliche<\/a>

Figure 5: The graphics show the poten\u00adtial energy savings and noise reduc\u00adtion in a direct compar\u00adison of on\/off oper\u00ada\u00adtion and infi\u00adnitely vari\u00adable speed adjust\u00adment.<\/p><\/div><\/div>\n

Partial-load oper\u00ada\u00adtion not only saves energy and lowers oper\u00adating costs, but also results in less waste heat. This is espe\u00adcially valu\u00adable for cooling appli\u00adca\u00adtions because heat that is not gener\u00adated does not need to be dissi\u00adpated. Commu\u00adta\u00adtion and the stator design also ensure very smooth oper\u00ada\u00adtion. The cycle frequen\u00adcies are acousti\u00adcally imper\u00adcep\u00adtible and noise reduc\u00adtion drops. This makes these \u201cstealth fans\u201d ideal for appli\u00adca\u00adtions in which the noise protec\u00adtion regu\u00adla\u00adtions must be observed.<\/p>\n

Simple commis\u00adsioning and world\u00adwide use<\/h2>\n

Prac\u00adtice-oriented design details simplify trans\u00adformer fan commis\u00adsioning. For example, it is possible to install and mount directly on the fan housing with a hori\u00adzontal or vertical instal\u00adla\u00adtion posi\u00adtion as required. The motor terminal box for supply connec\u00adtion and control is easily acces\u00adsible and isolated from the motor elec\u00adtronics. The devel\u00adop\u00adment team made a point of using high-quality termi\u00adnals. The fans are perfectly designed for world\u00adwide use. They func\u00adtion on power supplies between 200\u2009-240 V and 380\u2009-\u2009480 V (for 3-phase 50 Hz and 60 Hz grid frequen\u00adcies), satisfy all the rele\u00advant stan\u00addards (UL, CSA, EAC and CCC) and the require\u00adments of degree of protec\u00adtion IP55, and the rating label satis\u00adfies DIN EN 50216-12 (\u201cPower trans\u00adformer and reactor fittings\u201d \u2013 Part 12: Fans).<\/p>\n","protected":false},"excerpt":{"rendered":"

Trans\u00adformers generate waste heat when they are in oper\u00ada\u00adtion and oil is the coolant of choice. It trans\u00adfers the heat through convec\u00adtion (or supported by pump systems) to the trans\u00adformer housing, which has cooling fins or radi\u00ada\u00adtors similar to heat exchangers on the outside. Large high-power trans\u00adformers require addi\u00adtional cooling: fans that prevent damage from [\u2026]<\/p>\n","protected":false},"author":17,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"wp_typography_post_enhancements_disabled":false,"footnotes":""},"categories":[16],"tags":[124,133,33],"class_list":["post-12388","post","type-post","status-publish","format-standard","hentry","category-fans","tag-efficiency","tag-quiet","tag-saving-energy"],"acf":[],"_links":{"self":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/12388","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/users\/17"}],"replies":[{"embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/comments?post=12388"}],"version-history":[{"count":2,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/12388\/revisions"}],"predecessor-version":[{"id":16830,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/12388\/revisions\/16830"}],"wp:attachment":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/media?parent=12388"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/categories?post=12388"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/tags?post=12388"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}