The shaft load control component offers flexible control of both design and off-design specification of loads on any shaft in a GSP model. Use this component for specifying (usually power) turbine loads instead of the external load specifications in the turbine component which are meant for specification of constant and relatively small power off-take (PTO) auxiliary loads.
The loads can be specified in terms of torque and/or power (if both are specified, the loads are added together) and as a function of time in the transient input tab sheet. This component is especially useful to specify time dependent load variations (torque steps) on power turbines.
Power/torque load is the specified power/torque that is extracted from the shaft the Load component is connected to. If correctly configured (PWsurplus=0) than this of course corresponds to PWshaft (assuming single turbine on shaft) for steady-state. For transients, a power delta remains causing accels or decels.
Total shaft Power (and Torque) outputs (PW_total and TRQ_total) are calculated from the combined user specified power and torque (PW_spec, TRQ_spec). For example, if only a torque load is specified (as TRQ_spec input), power load (input) is 0 then PW_total is the power calculated from the torque (trq x rpm*60/2pi). If both power and torque are specified, the PW_total is calculated by "adding" the power and torque according to: user spec. power + user spec. torque * rpm*60/2pi. TRQ_total then is calculated by adding the torque converted from the PW_spec to the TRQ_spec.
Note that when using variable load in the transient input table to act upon a free power turbine, the free power turbine speed only changes during transient simulation ! For steady state calculations the turbine speed should be user specified (see the turbine component).
Shaft Load control
