GE 3658d SPEEDTRONIC™ MARK V GAS TURBINE CONTROL SYSTEM

GE 3658d SPEEDTRONIC™ MARK V GAS TURBINE  CONTROL SYSTEM

Description

The SPEEDTRONIC™ Mark V Gas Turbine Control System is the latest derivative in the highly successful SPEEDTRONIC™ series. Preceding systems were based on automated turbine control, protection and sequencing techniques dating back to the late 1940s, and have grown and developed with the available technology. Implementation of electronic turbine control, protection and sequencing originated with the Mark I system in 1968. The Mark V system is a digital implementation of the turbine automation techniques learned and refined in more than 40 years of successful experience, over 80% of which has been through the use of electronic control technology.

CONTROL SYSTEM HISTORY

The gas turbine was introduced as an industrial and utility prime mover in the late 1940s with initial applications in gas pipeline pumping and utility peaking. The early control systems were based on hydro-mechanical steam turbine governing practice, supplemented by a pneumatic temperature control, preset startup fuel limiting and manual sequencing. Independent devices provided protection against overspeed, overtemperature, fire, loss of flame, loss of lube oil and high vibration.

Through the early years of the industry, gas turbine control designs benefited from the rapid growth in the field of control technology. The hydro-mechanical design culminated in the “fuel regulator” and automatic relay sequencing for automatic startup, shutdown and cooldown where appropriate for unattended installations. The automatic relay sequencing, in combination with rudimentary annunciator monitoring, also allowed interfacing with SCADA (Supervisory Control and Data Acquisition) systems for true continuous remote control operation.

GAS TURBINE CONTROL PHILOSOPHY

• Single control failure alarms when running or during startup 

• Protection backs up control, thus independent 

• Two independent means of shutdown will be available 

• Double failure may cause shutdown, but will always result in safe shutdown 

• Generator-drive turbines will tolerate full-load rejection without overspeeding 

• Critical sensors are redundant 

• Control is redundant 

• Alarm any control system problems 

• Standardize hardware and software to enhance reliability while maintaining flexibility

SPEEDTRONIC™ MARK V CONTROL CONFIGURATION

The SPEEDTRONIC™ Mark V control system makes increased use of modern microprocessors and has an enhanced system configuration. It uses SIFT technology for the control, a new triple-redundant protective module and a significant increase in hardware diagnostics. Standardized modular construction enhances quality, speed of installation, reliability and ease of on-line maintenance. The operator interface has been improved with color graphic displays and standardized links to remote operator sta-tions and distributed control systems (DCS). 

Figure 8 shows the standard SPEEDTRONIC™ Mark V control system configuration. The top block in the diagram is the Interface Data Processor called <I>. It includes a monitor, keyboard, and printer. Its main functions are driving operator displays, managing the alarm process and handling operator commands. <I> also does system configuration and download, offline diagnostics for maintenance, and implements interfaces to remote operator stations and plant distributed control systems.