When a steam turbine loses its load, does its speed rise suddenly to very high levels?
Thread Content
When a compressor driven by a turbine is operating at its rated speed and the relief or return valve suddenly opens, will the speed rise sharply? Can the speed control system respond quickly enough?
It shouldn’t rise very high, as turbines are equipped with overspeed protection. When the speed exceeds the set value, the turbine’s safety device will activate, shutting off the steam supply to the turbine; safety interlocks are also established in the DCS!
The rotation speed should increase; as long as there are no issues during static testing before starting the machine, it shouldn’t overspeed. Mechanical or electronic speed controls can ensure that the machine shuts down in case of overspeeding. But when interlocks are in place, the operation becomes complicated. It is better to standardize the daily startup procedures