Control components are used to model the engine systems which actively affect the engine operating point.

GSP offers six standard controller types in the control component library in the following categories:

Fuel control components

These components control the fuel flow in order to control power level or maintain rotor speeds, and include:

Direct manual control of the fuel flow rate.

A generic control system component for modelling shaft speed governor controls (Proportional-Integral-Differential PID control) with acceleration control included. Use this control for simple turbojet and turbofan engine control.

•Turboshaft Fuel Control

A component inheriting all characteristics of the above governor control with in addition a separate generic power turbine shaft speed control PID governor model. Use this control for customary turboshaft engine controls.

Variable geometry components

•Compressor Bleed Control

Controls off-design bleed flow rates.

•Manual Variable Exhaust Nozzle Control

Off-design manual control of a variable exhaust nozzle

Variable inlet guide vanes (VIGV) and stator vane (VSV) control components are inherited from these components and obtainable as custom components (not included in the public GSP version).

Load control components

These components provide a means to specify varying off-design (transient) power turbine loads in terms of torque and/or power levels, and include:

•Shaft Load control

Propellor and helicopter rotor models calculating turbine loads are inherited from this component and obtainable as custom component (not included in the public GSP version).

Note: steady state and steady state series calculations may become problematic when control system components with engine parameter feedback depending on time (such as Gas Generator Fuel control and Turboshaft Fuel control components) are used in the model. The best way to calculate a steady state point then is to stabilize at the particular operating point using a transient calculation first before performing a steady state calculation.

Most control components can be enabled/disabled by checking/unchecking the active checkbox on the general tab sheet of the component property window. A disabled component will display a red cross in the top left corner of the component icon in the model window.

Below displays a disabled (thrust controller nr.1) and an enabled (thrust controller nr.2) controller

ThrustCtrls_EnDisabled