ABB SPTPS13 H R Series turbine control solutions

a turbine trip.
• Turbine Trip (TRIP): Operates in parallel with or in lieu of the OEM electrical turbine trip
(typically a solenoid dump valve in the turbine control oil circuit) that rap-idly shuts all
of the turbine valve actuators. The setpoint is typically 110% of rated turbine speed.
• EHC Protection (EHC): Operates in conjunction with the TRIP function to acti-vate
the EHC Manifold, which dumps the hydraulic pressure to all of the valve actuators.
The setpoint is the same as the TRIP setpoint.
• Power Load Imbalance (PLI): Megawatts (electrical load output) and Intermediate
Pressure (IP) Turbine Exhaust Pressure (mechanical load input) are compared to
determine if there is an imbalance between the two. If the turbine mechanical load
input exceeds the electrical load output by a set amount, an overspeed situation is
anticipated and a digital output is generated for a specified time period, which is
typically used to briefly close the Intercept Valves.

FCS Mode
FCS mode is strictly a speed detection mode, where no protection functions are being applied locally by the SPTPS13 module. The speed channel channel is the only physical I/O channel that is used in this mode. Turbine speed is calculated by the TPS13 and passed through to the main controller (BRC4XX) via Expander Bus.
TSA Mode
The TSA mode provides turbine speed detection and calculation, overspeed protection and acceleration calculation. In addition, the TAS mode includes hardware based speed probe
failure diagnostics designed to detect most speed probe open and short circuit conditions.
Under the TSA mode of operation, the overspeed setpoint of the SPTPS13 can be automatically adjusted making use of a set of three digital inputs: Auto, Manual,
and Test. In the code, the module calculates each of these setpoints, stores them
in an array, and selects one for the overspeed setpoints based on the state of the
Digital Inputs every cycle.
The TSA01 will detect an overspeed once the calculated turbine speed exceeds the current threshold value as determined by the state of the digital inputs. Upon detecting the overspeed condition, the SPTPS13’s only action is to activate the digital outputs (no additional signals are sent through XBUS).