modelGovernor

Governor/control model

Extends from OpenHPL.Icons.Governor (Governor icon).

Information

Governor

Here, a simple model of the governor that controls the guide vane opening in the turbine based on the reference power production is described. The block diagram of this governor model is shown in the figure.

Governor block diagram

Figure: Block Diagram of the governor.

Implementation

Using the model in the figure and the standard Modelica blocks, the governor model is encoded in our library as the Governor unit. This unit has inputs as the reference power production and generator frequency that are implemented with the standard Modelica RealInput connector. This Governor unit also uses the standard Modelica RealOutput connectors in order to provide output information about the turbine guide vane opening.

Parameters

In the Governor unit (note: in the text it mentions SynchGen but this appears to be a typo in the original document - should be Governor), the user can specify the various time constants of this model (see figure): pilot servomotor time constant Tp, primary servomotor integration time Tg, and transient droop time constant Tr. The user should also provide the following parameters: droop value σ, transient droop δ, and nominal values for the frequency and power generation. The information about the maximum, minimum, and initial guide vane opening should also be specified.

The model is taken from [Sharefi2011].

Parameters

TypeNameDefaultDescription
Controller settings
SI.TimeT_p0.04Pilot servomotor time constant
SI.TimeT_g0.2Main servomotor integration time
SI.TimeT_r1.75Transient droop time constant
Realdroop0.1Droop
Realdelta0.04Transient droop
System settings
Real[:,:]lookup_table[0.0, 0.0; 0.01, 0.06; 0.22, 0.25; 0.53, 0.5; 0.8, 0.75; 1.0, 0.95; 1.05, 1.0]Table matrix (grid = first column; e.g., table=[0, 0; 1, 1; 2, 4])
RealY_gv_max0.05Max guide vane opening rate
RealY_gv_min0.2Max guide vane closing rate
RealY_gv_ref0.72151Initial guide vane opening rate
SI.Frequencyf_refdata.f_0Reference frequency
SI.PowerPn104e6Reference power

Connectors

TypeNameDefaultDescription
Modelica.Blocks.Interfaces.RealInputP_ref
Modelica.Blocks.Interfaces.RealOutputY_gv
Modelica.Blocks.Interfaces.RealInputf

Components

TypeNameDefaultDescription
DatadataUsing standard class with constants
Modelica.Blocks.Tables.CombiTable1Dvlook_up_table
Modelica.Blocks.Continuous.TransferFunctionpilot_servo
Modelica.Blocks.Continuous.TransferFunctionmain_servo
Modelica.Blocks.Math.Gaingain_T_s
Modelica.Blocks.Nonlinear.Limiterlimiter_dotY_gv
Modelica.Blocks.Nonlinear.Limiterlimiter_Y_gv
Modelica.Blocks.Continuous.TransferFunctioncontrol
Modelica.Blocks.Math.Gaingain_droop
Modelica.Blocks.Math.Gaingain_P
Modelica.Blocks.Math.Addadd1
Modelica.Blocks.Math.Add3add2
Modelica.Blocks.Math.Addadd3
Modelica.Blocks.Math.Gaingain_f
Modelica.Blocks.Sources.Constantconst
Modelica.Blocks.Math.Gaingain_droop2