GE 151X1225DE03PC01 Drive Control Board (Terminal Control)

151X1225DE03PC01    Drive Control Board (Terminal Control)

Transfer to Manual Regulator upon Loss of PT detects loss of PT feedback

voltage to the ac voltage regulator. If the sensing voltage is lost, the regulator forces its

Output to the ceiling for 0.5 seconds and then switch to manual mode.

This is significantly different from… the PTFD function, which does not force the regulator to ceiling before transferring.

Underexcitation Limiter (UEL) is an auxiliary control to limit the AVR demand for

underexcited reactive current. The UEL prevents reductions of the generator field

excitation to a level where the small-signal (steady state) stability limit or the stator core

end-region heating limit is exceeded. Performance is specified by identifying the region

of the limiter action on the generator capability curve.

Unit Data Highway Interface (UDH) connects the exciter with the turbine control

system, HMI or HMI viewer/data server, and GE controls. The UDH is based on EGD

protocol. The UDH provides a digital window into the exciter where variables can be

monitored and controlled. It also supports the ToolboxSTapplication configuration and

maintenance tool for the exciter.

VAR/PF Control is accomplished by slow ramping of the AVR reference setpoint.

The VAR/PF is selected by operator command and the VAR/PF value is controlled using

the raise/lower push-buttons. When the exciter interfaces with a Mark VIe turbine control

system, this function is typically included.

Volts per Hertz Limiter (V/Hz Lim) limits the generator V/Hz ratio to the

programmed setting in the EX2100e. This function uses two inputs from the software

transducer, average generator voltage and generator frequency (its V/Hz ratio is

configurable). Typically, the generator is considered to be operating acceptably within

±5% of rated terminal voltage at rated frequency.

Volts per Hertz Protection (V/Hz 24G) serves as a backup to the V/Hz limiter. The

protection scheme consists of two levels of V/Hz alarm and trip protection. Typically, one

The level is set at 1.10 per unit over V/Hz with an inverse time period, and the other level is set at 1.18 per unit with a two-second time period.

When out-of-limit operation causes the exciter to trip, the controller stops gating the

power converter IGBTs. The field current flows back into the dc link and rapidly

collapses as its energy transfers into the dc link capacitors. To prevent overvoltage of the

dc link, the dynamic discharge (DD) resistor is automatically connected across the dc link

to dissipate the energy from the field

designed to start a gas turbine-generator set. By operating the generator as a

synchronous motor, the Static Starter accelerates the turbine set according to a

specific speed profile that provides optimum starting conditions for the gas turbine.

The LS2100 eliminates the need for separate starting hardware, such as an electric

motor or diesel engine, torque converters, and associated auxiliary equipment, thus

opening up critical space around the turbine base.

The LS2100 has a digital control that interfaces seamlessly with the Mark VI gas

turbine control, the EX2100 excitation control, the Human-Machine Interface

(HMI), and the PI Historian. These devices communicate with each other over an

Ethernet®- based data highway to form a fully integrated control system. The GE

Control Systems Toolbox (toolbox) is used to configure the LS2100 control. This is

the same toolbox  used to configure the Mark VI gas turbine control and EX2100

excitation control.

The LS2100 static power

converter is available in two

power ratings (8.5 and 14

MVA) designed to provide an

optimal match to the starting

power requirements for both

GE 7 and 9 gas turbine

generator sets, respectively.