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What are the functions of the rotor coil, rotor core, stator coil, and stator core in a QF-3-2 type generator? The function of the rotor coil in this type of generator is to provide the excitation current, while the stator coil generates three-phase alternating current. The rotor core and stator core serve to create a magnetic path for the generator. What is the purpose of the coaxial excitation machine in the QF-3-2 type generator? The coaxial excitation machine in this generator provides the excitation current necessary for the rotor to generate a magnetic field, thereby enabling the stator windings to produce electricity. What is the function of the excitation coil? Its role is to provide an excitation current to the exciter, enabling the exciter to generate voltage and supply an excitation current to the generator. What are the hazards of connecting a generator to the grid out of synchronization? The main hazard is the occurrence of active power circulation, which causes significant mechanical stress on the generator; in severe cases, the generator can be damaged due to the intense mechanical forces involved. Is the situation of connecting transformers with different winding connections in parallel the most hazardous? When transformers with different winding connections are connected in parallel, and several requirements for such parallel connection are not met, its hazard level is generally the highest. Because the impact is greatest, and so is the destructiveness. How are inductive reactive power and capacitive reactive power generated? Why does inductive reactive power lead to demagnetization while capacitive reactive power leads to magnetization? Why is it possible to adjust frequency using active power and voltage using reactive power when the speed of the generator remains constant? The generation of inductive reactive power and capacitive reactive power is related to the temporary storage of energy; when inductive reactive power is consumed, components store electrical energy temporarily in the form of a magnetic field, whereas components that consume capacitive reactive power store electrical energy temporarily in the form of an electric field. The demagnetization of reactive inductive and capacitive reactance is mainly related to the nature of their armature reaction. The armature magnetic field generated by reactive power has a lagging nature, and the corresponding armature reaction has a demagnetizing effect, which can be analyzed using phasor diagrams. By the same logic, the capacitive reactive armature magnetic field has a leading nature, and the corresponding armature reaction has a magnetizing nature. By adjusting the mechanical power input to the generator, the output active power tends to increase. If the load remains constant, both the speed and frequency will increase (rather than the speed remaining unchanged). If the speed and frequency stay constant, then the output active power will increase ； By adjusting the excitation voltage of the generator, the terminal voltage of the generator tends to increase, which causes the phase of the current output by the synchronous generator to become leading; as a result, the reactive power it outputs changes. Thus, there is the saying of “active power for frequency regulation, reactive power for voltage regulation”. This post was last edited by 156026692 on 2009-2-11 19:46]