Mas­ter­ing Dan­ger­ous Vibra­tions

AIC: Act­ive damp­ing of com­bus­tion os­cil­la­tions

If the sharp curve can­not be avoided, then please use trac­tion con­trol! The same ap­plies to the AIC (ACTIVE INSTABILITY CONTROL) - still a tech­nic­ally unique solu­tion for the act­ive reg­u­la­tion of com­bus­tion os­cil­la­tions and com­pressor in­stabil­it­ies with act­ive damp­ing. This soph­ist­ic­ated pro­tec­tion concept is used es­pe­cially in areas where con­ven­tion­al meth­ods fail, i.e. where the "bend­ing road" can­not be seen in time. AIC con­tains the com­pon­ents for sig­nal meas­ure­ment + stor­age + act­ive pro­tec­tion using spe­cial high-per­form­ance valves and lin­ear mo­tors in real-time. This al­lows to sta­bil­ize a flame or to blow away a stall cell.

Act­ive damp­ing with AIC has no al­tern­at­ive, es­pe­cially in situ­ations where it is not pos­sible to avoid com­bus­tion os­cil­la­tions, e.g. due to a change in com­bus­tion con­trol.


  • Meas­ure­ment
  • Ana­lys­is
  • Mon­it­or­ing
  • Act­ive Damp­ing
  • Act­ive damp­ing of self-ex­cited com­bus­tion os­cil­la­tions, also known as ther­moacous­tic os­cil­la­tions, pulsa­tions or hum­ming
  • Use in tur­bines: from single burn­er to mul­tiple burn­er plants to large sta­tion­ary gas tur­bines
  • Well-proven sys­tem for world­wide use in large sta­tion­ary gas tur­bines of mod­ern com­bined cycle power plants

What Makes the Act­ive In­stabil­ity Con­trol (AIC) Unique?

Ad­vant­ages of the AIC

Com­pared to the IfTA Ar­gusOMDS sys­tem, the IfTA AIC sys­tem dif­fers primar­ily by the DSP firm­ware. In the in­dustry, the re­ac­tion speed is re­garded as out­stand­ing - sample by sample is pro­cessed and con­trolled in real-time.

  • Ac­quis­i­tion of up to 16 sensor sig­nals and con­trol of up to 32 ac­tu­at­ors
  • Auto­mat­ic set­ting of the con­trol para­met­ers
  • Mod­u­lar design
  • Com­plete in­teg­ra­tion into the con­trol sys­tem via di­git­al, ana­log or field-bus in­ter­faces such as Profib­us, Mod­bus, Can-Bus

Fields of ap­plic­a­tion:

  • In­dus­tri­al or sta­tion­ary gas tur­bines
  • Large in­dus­tri­al com­bus­tion sys­tems such as pro­cess gas heat­ers

Act­ive vs. pass­ive pro­tec­tion

Com­pared to pass­ive pro­tect­ive meas­ures, AIC of­fers the fol­low­ing ad­vant­ages:

  • Easy up­grade for ex­ist­ing ap­plic­a­tions
  • No cost and time in­tens­ive ret­ro­fit­ting of the com­bus­tion sys­tem ne­ces­sary
  • Ef­fi­ciency, sta­bil­ity and con­struc­tion of the com­bus­tion sys­tem are not neg­at­ively af­fected - no ad­di­tion­al losses occur due to the Argus AIC sys­tem
  • Pol­lut­ant emis­sions are even par­tially re­duced, e.g. NOx and un­burned fuel/gas
  • The con­trol is able to adapt to the ac­tu­al sys­tem be­ha­vi­or and its changes

Act­ive In­stabil­ity Con­trol for Sta­tion­ary Gas Tur­bines

Siemens Re­lies on Proven IfTA Tech­no­logy

As a res­ult of many years of uni­ver­sity re­search work by Dr.-Ing. Jakob Her­mann (gen­er­al man­ager IfTA GmbH) in this field, IfTA GmbH suc­ceeded for the first time in 1997 in suc­cess­fully ap­ply­ing this tech­no­logy to large sta­tion­ary gas tur­bines with an out­put of over 240 MW from Siemens AG to es­tab­lish it as an in­dustry stand­ard.

Sys­tems in wide­spread use

Since 1997, ap­prox­im­ately 50 of these sys­tems have been suc­cess­fully im­ple­men­ted in sta­tion­ary gas tur­bines world­wide. In ad­di­tion to their high ef­fi­ciency in the damp­ing of com­bus­tion os­cil­la­tions, their out­stand­ing fea­tures in­clude high sys­tem avail­ab­il­ity and re­li­ab­il­ity, which led to un­res­tric­ted cus­tom­er ac­cept­ance and high sat­is­fac­tion.