METHOD OF PREVENTING DEVIATION OF PARAMETERS OF POWER TURBINE OF TURBOMACHINE SET AT ABRUPT COMPLETE OR PARTIAL SHEDDING OF LOAD Russian patent published in 2004 - IPC

FIELD: mechanical engineering; protection of turbomachine sets. SUBSTANCE: invention relates to protection of turbomachine sets including gas-turbine sets (gas turbines and machines, for instance, generators driven by said gas turbines) from dangerous overspeeds at abrupt complete or partial shedding of load. Proposed method includes supply of signals indicating power turbine rotor speed (n_pt), gas generator rotor speed (n_gg) and one of load parameters, shaping of signal to control fuel consumption in combustion chamber, and, according to invention, value of thermodynamic parameter of gas generator is additionally determined and compared with corresponding threshold value and in case of simultaneous supply of signal indicating that parameter value exceeds threshold value and signal indicating abrupt complete or partial shedding of load, is received, order is sent to switch on ignition for preset time and switch off fuel delivery into combustion chamber, and value n_gg is additionally compared with corresponding threshold value nthrgg

, and value n_pt is compared with corresponding threshold value nthrpt, first derivative of power turbine rotor speed n_pt is found and compared with corresponding threshold value nthrpt and increment of rotor speed Δn_pt shedding of load is found, and further, if n_pt<nthrpt;|n_pt|<nthrpt,Δn_pt<0 and n_gg>nthrgg, signal is supplied to switch of fuel delivery into combustion chamber. Thermodynamic parameter of gas generator and/or parameter of load gas generator rotor speed n_gg or gas generator rotor speed n_ggred reduced to temperature at inlet. Full air pressure after compressor P*c can serve as thermodynamic parameter of gas generator, and power of electric generator P_gen set into operation by power turbine of turbomachine set serve as load parameter. EFFECT: improved safety owing to prevention of overspeeding of power turbine which can damage equipment, input personnel or cut off power supply by short-time cutting off fuel delivery into combustion chamber. 4 cl, 1 dwg