V2 Compatible Hydro Governor (HGOV18)

 

Description

This component models an IEEE type 2 hydro governor and turbine and was created specifically to retrofit the later, more compact version of the V2 SNC375 Machine Model (Obsolete).  It is included in the PSCAD V4 Master Library for compatibility reasons.

 

Inputs:

Outputs:

 

More:

Governor Models

Hydro Governor Transfer Functions

PSCAD references [1], [2] and [3]

Input Parameters

ConfigurationConfiguration

NOTE:  See Hydro Governor Transfer Functions for more details.

 

 Name for Identification

 

Text

 

Optional text parameter for identification of the component.

         

 Base Frequency

 

REAL

Constant

Enter the system base frequency for per-unitizing [Hz]

 

 

 

 

 

Controller Real Pole Gain

 

REAL

Constant

 

 

 

 

 

 

Controller Proportional Gain

 

REAL

Constant

 

 

 

 

 

 

Controller Integral Gain

 

REAL

Constant

 

 

 

 

 

 

Controller Real Pole Time Constant

 

REAL

Constant

[s]

 

 

 

 

 

Turbine Lead Time Constant

 

REAL

Constant

[s]

 

 

 

 

 

Turbine Lag Time Constant

 

REAL

Constant

[s]

 

 

 

 

 

Governor Time Constant

 

REAL

Constant

[s]

 

 

 

 

 

Inverse Gate Velocity Limit

 

REAL

Constant

Physically, this is the time required, in seconds, for the gate to go from fully closed to fully open [s/pu]

 

 

 

 

 

Gate Velocity Time Constant

 

REAL

Constant

[s]

 

 

 

 

 

Permanent Droop Gain

 

REAL

Constant

 

 

 

 

 

 

Gate Position Control Rate Limit

 

REAL

Constant

This limits the rate at which the 'desired gate position' signal may change [pu/s]

 

 

 

 

 

Temporary Droop Gain

 

REAL

Constant

 

 

 

 

 

 

Temporary Droop Time Constant

 

REAL

Constant

[s]

 

 

 

 

 

Conversion Constant

 

REAL

Constant

Conversion constant from per-unit gate position to per-unit mechanical torque.

 

Example:  A 120MVA generator operates at a power factor of 0.85.  The rated turbine output must be 0.85x120 or 102 MW.  If the turbine is designed to deliver this power at 95% gate, the power rating of the turbine would be 102/0.95 or 107.4 MW. Thus this conversion constant is 107.4/120.0 or 0.89.

 

Note that the governor output is limited by the Conversion Constant parameter.  If the machine output is more than the Conversion Constant at the time of transition, when the governor is released, it will restrict the output to the Conversion Constant and the machine speed will drop.  Hence take this factor into consideration while loading the machine.

 

 

 

 

 

Time Constant for Smoothing TmO

 

REAL

Variable

The mechanical torque from the machine needs to be smoothed to remove any ripple before it can be used for initializing the governor.  The Tm0 input is passed through a real pole block with this time constant before it is used.  This block is not a part of the governor dynamics and it is active only during the initialization [s]

 

 

 

 

 

Initialization switch: 0-Init; 1-Release

 

INTEGER

Variable

Use the machine initialization switch here.  During the initialization period (0), the governor will continuously initialize itself to the machine's mechanical torque output.  Thus when the machine is released, the governor will output the machine torque from its last time step and the transition will be smooth.  This also avoids the need to supply the initial mechanical torque.