GovCT1

Class Description

General model for any prime mover with a PID governor, used primarily for combustion turbine and combined cycle units.
This model can be used to represent a variety of prime movers controlled by PID governors. It is suitable, for example, for the representation of:

  • gas turbine and single shaft combined cycle turbines
  • diesel engines with modern electronic or digital governors
  • steam turbines where steam is supplied from a large boiler drum or a large header whose pressure is substantially constant over the period under study
  • simple hydro turbines in dam configurations where the water column length is short and water inertia effects are minimal.
Additional information on this model is available in the 2012 IEEE report, Dynamic Models for Turbine-Governors in Power System Studies, 3.1.2.3 pages 3-4 (GGOV1).

Attributes

Name Type Description
aset Float Acceleration limiter setpoint (Aset). Unit = PU / s. Typical value = 0,01.
db PU Speed governor deadband in PU speed (db). In the majority of applications, it is recommended that this value be set to zero. Typical value = 0.
dm PU Speed sensitivity coefficient (Dm). Dm can represent either the variation of the engine power with the shaft speed or the variation of maximum power capability with shaft speed. If it is positive it describes the falling slope of the engine speed verses power characteristic as speed increases. A slightly falling characteristic is typical for reciprocating engines and some aero-derivative turbines. If it is negative the engine power is assumed to be unaffected by the shaft speed, but the maximum permissible fuel flow is taken to fall with falling shaft speed. This is characteristic of single-shaft industrial turbines due to exhaust temperature limits. Typical value = 0.
ka PU Acceleration limiter gain (Ka). Typical value = 10.
kdgov PU Governor derivative gain (Kdgov). Typical value = 0.
kigov PU Governor integral gain (Kigov). Typical value = 2.
kiload PU Load limiter integral gain for PI controller (Kiload). Typical value = 0,67.
kimw PU Power controller (reset) gain (Kimw). The default value of 0,01 corresponds to a reset time of 100 s. A value of 0,001 corresponds to a relatively slow-acting load controller. Typical value = 0,01.
kpgov PU Governor proportional gain (Kpgov). Typical value = 10.
kpload PU Load limiter proportional gain for PI controller (Kpload). Typical value = 2.
kturb PU Turbine gain (Kturb) (> 0). Typical value = 1,5.
ldref PU Load limiter reference value (Ldref). Typical value = 1.
maxerr PU Maximum value for speed error signal (maxerr) (> GovCT1.minerr). Typical value = 0,05.
minerr PU Minimum value for speed error signal (minerr) (< GovCT1.maxerr). Typical value = -0,05.
mwbase ActivePower Base for power values (MWbase) (> 0). Unit = MW.
r PU Permanent droop (R). Typical value = 0,04.
rclose Float Minimum valve closing rate (Rclose). Unit = PU / s. Typical value = -0,1.
rdown PU Maximum rate of load limit decrease (Rdown). Typical value = -99.
ropen Float Maximum valve opening rate (Ropen). Unit = PU / s. Typical value = 0.10.
rselect DroopSignalFeedbackKind Feedback signal for droop (Rselect). Typical value = electricalPower.
rup PU Maximum rate of load limit increase (Rup). Typical value = 99.
ta Seconds Acceleration limiter time constant (Ta) (> 0). Typical value = 0,1.
tact Seconds Actuator time constant (Tact) (>= 0). Typical value = 0,5.
tb Seconds Turbine lag time constant (Tb) (> 0). Typical value = 0,5.
tc Seconds Turbine lead time constant (Tc) (>= 0). Typical value = 0.
tdgov Seconds Governor derivative controller time constant (Tdgov) (>= 0). Typical value = 1.
teng Seconds Transport time delay for diesel engine used in representing diesel engines where there is a small but measurable transport delay between a change in fuel flow setting and the development of torque (Teng) (>= 0). Teng should be zero in all but special cases where this transport delay is of particular concern. Typical value = 0.
tfload Seconds Load-limiter time constant (Tfload) (> 0). Typical value = 3.
tpelec Seconds Electrical power transducer time constant (Tpelec) (> 0). Typical value = 1.
tsa Seconds Temperature detection lead time constant (Tsa) (>= 0). Typical value = 4.
tsb Seconds Temperature detection lag time constant (Tsb) (>= 0). Typical value = 5.
vmax PU Maximum valve position limit (Vmax) (> GovCT1.vmin). Typical value = 1.
vmin PU Minimum valve position limit (Vmin) (< GovCT1.vmax). Typical value = 0,15.
wfnl PU No load fuel flow (Wfnl). Typical value = 0,2.
wfspd Boolean Switch for fuel source characteristic to recognize that fuel flow, for a given fuel valve stroke, can be proportional to engine speed (Wfspd).
true = fuel flow proportional to speed (for some gas turbines and diesel engines with positive displacement fuel injectors)
false = fuel control system keeps fuel flow independent of engine speed.
Typical value = true.

Relationships

Inherits from

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Leaf/Root class

IsLeaf IsRoot
False False

Associations

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