Manual 35018V1
505XT Digital Control System for Steam Turbines
Woodward
130
OFF-LINE PROPORTIONAL GAIN
dflt= 5.0 (0.0, 100)
Enter the off-line PID proportional gain percentage. This value is used to set speed/load control
response when the Generator or Utility Tie breaker contacts are open (if the unit is a generator) or if
the turbine speed is below minimum governor speed (if the unit is not a generator) or when the
Select Dynamics function is used and the contact is open. This value can be changed in the Run
Mode while the turbine is operating. A recommended starting value is 5%.
OFF-LINE INTEGRAL GAIN
dflt= 0.5 (0.01, 50)
Enter the off-line PID integral gain percentage. This value is used to set speed/load control response
when the Generator or Utility Tie breaker contacts are open (if the unit is a generator) or if the turbine
speed is below minimum governor speed (if the unit is not a generator) or when the Select Dynamics
function is used and the contact is open. This value can be changed in the Run Mode while the
turbine is operating. A recommended starting value is 0.5%.
OFF-LINE DERIVATIVE RATIO
dflt= 5.0 (0.01, 100)
Enter the off-line PID derivative ratio. This value is used to set speed/load control response when the
Generator or Utility Tie breaker contacts are open (if the unit is a generator) or if the turbine speed is
below minimum governor speed (if the unit is not a generator) or when the Select Dynamics function
is used and the contact is open. This value can be changed in the Service Mode while the turbine is
operating. When this value is between 0.01 and 1.0, the derivative term is considered to be ‘input
dominant’ and the derivative is equal to (Deriv Ratio)/(Integral Gain). When this value is between 1.0
and 100, the derivative term is considered to be ‘feedback dominant’ and the derivative is equal to
1.0/[(Deriv Ratio)*(Integral Gain)].
ON-LINE PROPORTIONAL GAIN
dflt= 5.0 (0.0, 100)
Enter the on-line PID proportional gain percentage. This value is used to set speed/load control
response when the Generator and Utility Tie breaker contacts are closed (if the unit is a generator)
or if the turbine speed is above minimum governor speed (if the unit is not a generator) or when the
Select Dynamics function is used and the contact is closed. This value can be changed in the Run
Mode while the turbine is operating. A recommended starting value is 5%.
ON-LINE INTEGRAL GAIN
dflt= 0.5 (0.01, 50)
Enter the on-line PID integral gain percentage. This value is used to set speed/load control response
when the Generator and Utility Tie breaker contacts are closed (if the unit is a generator) or if the
turbine speed is above minimum governor speed (if the unit is not a generator) or when the Select
Dynamics function is used and the contact is closed. This value can be changed in the Run Mode
while the turbine is operating. A recommended starting value is 0.5%.
ON-LINE DERIVATIVE RATIO
dflt= 5.0 (0.01,100)
Enter the on-line PID derivative ratio. This value is used to set speed/load control response when the
Generator and Utility Tie breaker contacts are closed (if the unit is a generator) or if the turbine
speed is above minimum governor speed (if the unit is not a generator) or when the Select Dynamics
function is used and the contact is closed. This value can be changed in the Service Mode while the
turbine is operating. See Chapter 5—PID Dynamics Settings for more information. When this value is
between 0.01 and 1.0, the derivative term is considered to be ‘input dominant’ and the derivative is
equal to (Deriv Ratio)/(Integral Gain). When this value is between 1.0 and 100, the derivative term is
considered to be ‘feedback dominant’ and the derivative is equal to 1.0/[(Deriv Ratio)*(Integral
Gain)].
Operating Parameters Block
GENERATOR APPLICATION?
dflt= NO (Yes/No)
Select YES if the turbine is driving a generator. If YES, requires a Generator breaker and Utility Tie
breaker to be programmed as contact inputs. If NO, skip to the ‘Use Local/Remote’ question.
USE GEN BREAKER OPEN TRIP?
dflt= NO (Yes/No)
Select YES if opening the generator breaker is to initiate a turbine trip. If YES, the unit will trip when
the generator breaker opens after being closed, unless a Controlled Stop is selected. If NO, the
speed set point will instantly reset to the ‘Gen Open Set Point’ which is defaulted to 50 rpm below
rated speed.