caa a22 4500 477130542 CHVBK 20180405111703.0 cr unu---uuuuu 170330e19971201xx s 000 0 eng 10.1007/BF02766229 doi (NATIONALLICENCE)springer-10.1007/BF02766229 Initial breaking speed of hydroelectric units [Elektronische Daten] [A. Avrorov, G. Pinskii, G. Pirogov] Conclusions: 1. In the majority of hydraulic-turbine generators with r ≤ 0.002, electric braking may be used without apprehension; this braking process is suspended in the zone of the ascending branch of the torque curve, since the total mechanical braking torque provides for braking of the hydroelectric unit to n1/nn=0.14\2-0.16. For machines with a lower stator-winding resistance, it is necessary to perform a detailed calculation. If it is found from the results of the calculation that the braking torque is insufficient within some range of rotational speeds, it is necessary to incorporate a series-resistance stator in the circuit. 2. The magnitude of synchronous inductive impedance exerts an influence primarily only on the minimum rotational speed at which braking of the hydroelectric unit is suspended (n2); this corresponds to the descending branch of the electric-braking curve. As for the second root of Eq. (7a), n1/nn≈100r, i.e., as is apparent from (8), xd has virtually no effect on n1. 3. For any ratio of parameters of the hydraulic-turbine generators, the minimum rotational speed n2 at which the rotational torque and braking torque of the hydroelectric unit are equal is less than 0.05% of the nominal. It therefore follows that the setting for the automatic application of brakes at the end of the electric-braking process may be very low, and selection of the setting may conform only to the condition that the signal for braking was rather stable in terms of speed. Plenum Publishing Corporation, 1998 Avrorov A. aut Pinskii G. aut Pirogov G. aut Hydrotechnical Construction Springer-Verlag 31/12(1997-12-01), 729-732 0018-8220 31:12<729 1997 31 10749 https://doi.org/10.1007/BF02766229 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02766229 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Avrorov A. aut NATIONALLICENCE 700 1- Pinskii G. aut NATIONALLICENCE 700 1- Pirogov G. aut NATIONALLICENCE 773 0- Hydrotechnical Construction Springer-Verlag 31/12(1997-12-01), 729-732 0018-8220 31:12<729 1997 31 10749 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer