Electronic Speed Control - MAN Diesel & Turbo

Electronic Speed ControlRetrofit for steam turbines

Electronic Speed ControlImproved protection for steam turbinesSteam turbine type DEK 710 equipped with the newly designed speed control systemIn order to meet the new requirements of API 670 for control and protectionsystems for steam turbines, MAN PrimeServ has developed a new retrofit standardof a fully redundant electro-hydraulic speed control system and SIL certifiedelectronic overspeed protection system. This retrofit solution is recommended toall customers with previous installations of simplex pneumatic-hydraulic speedcontrol systems and hydraulic overspeed protection systems of steam turbinestype DG/DK/DEG/DEK.

Speed controller ARedundant speed controller4/3-way valve ARedundant control blockAngular trans. ARotary deviceSpeed controller B4/3-way valve BAngular trans. BLP controlSpeed controller ARedundant speed controller4/3-way valve ARedundant control blockAngular trans. ARotary deviceSpeed controller B4/3-way valve BAngular trans. BHP controlControl oilTrip-valve oil2v3 valve block2v3 overspeedprotectionSteamRetrofit scheme for extraction steam turbine type DEKChallengeThe operation of steam turbines requires a reliableand accurate speed control and overspeed protectionsystem. In order to meet the new requirements ofAPI 670 for control and protection systems, MANPrimeServ provides a new, fully redundant electrohydraulicspeed control system and fully electronicoverspeed protec tion system as a replacement for theprevious simplex pneumatic-hydraulic speed controlsystems and hydraulic overspeed protection systems.SolutionThe newly designed speed control system consists of acompact control block with redundant 4/3-way valvesattached, a rotary device with angular transmitter and aspeed controller. The oil supply will include bladderaccumu lator and double oil filter. In order to achievemaximum machine availability and safety during operation,the new overspeed protection system is fully electronicwith 2-out-of-3 voting and SIL 3 capability.The units are designed to replace previous types ofsimplex pneumatic-hydraulic speed control systemsand hydraulic overspeed protection systems for DG/DK/DEG/DEK steam turbines. It is therefore recommendedto all customers with installations includingsuch machines.Advantages• maximum machine availability and safety duringoperation by complete redundant design of thecontrol loops• single components can be replaced duringoperation without complete machine shutdown• monitoring and visualisation of the machine viaDCS (Distributed Control System)• malfunction monitoring of single control loopcomponents eases and shortens maintenance work• automatic shock-proof switchover of the controlloops with alarm• cost efficient and SIL3 certified overspeedprotection system• E/H control of the trip valve via 2-out-of-3 logic• compact design of the rotary device withminimised oil leakage (electronic speed control)• control block oil supply equipped with double oilfilter for maximum reliability• IPC for datalogging in control cabinet

Copyright © MAN Diesel & Turbo · Subject to modification in the interest of technical progress. · D02081041EN Printed in Germany GMC-OBH06100.5MAN Diesel & Turbo13507 Berlin, GermanyPhone +49 30 440402 2716Fax +49 30 440402 2909mtprimeserv@man.euwww.mandieselturbo.com24/7 Hotline: +49 208 692 9000MAN PrimeServ – a service brand of MAN Diesel & Turbo