초록 ▼

An excitation system for a brushless synchronous alternator includes an exciter having a stator which includes first and second sets of field coils respectively coupled to a source of DC power and in series with polyphase AC output current developed by the main generator. A base level of exciter fie

An excitation system for a brushless synchronous alternator includes an exciter having a stator which includes first and second sets of field coils respectively coupled to a source of DC power and in series with polyphase AC output current developed by the main generator. A base level of exciter field current is provided by the DC current delivered to the first set of field coils while a second variable amount of field current is provided by the AC output current delivered to the second set of field coils. The exciter also includes a rotor structure having first and second sets of armature windings which develop first and second exciter currents in response to movement of the rotor structure within the magnetic fields set up by the first and second sets of exciter field coils. The first and second exciter currents are added, rectified and delivered to a set of main generator field windings. By dividing the responsibility for providing exciter field current in this fashion, transient response is improved and overall length and weight of the generator package are decreased.

대표청구항 ▼

In an alternator driven by a source of motive power for energizing a load having an exciter for developing an exciter output current, a main generator coupled to the load and to the exciter for developing output currents from the exciter output current, means including a source of direct current for

In an alternator driven by a source of motive power for energizing a load having an exciter for developing an exciter output current, a main generator coupled to the load and to the exciter for developing output currents from the exciter output current, means including a source of direct current for establishing an exciter field, each of the exciter and main generator having a moving rotor assembly coupled to the source of motive power and a stationary stator disposed adjacent the rotor with the rotor assembly and stator having conductors disposed thereon forming field and armature coils, the improvement comprising: the exciter field coils include first and second sets of field windings wherein the first set of field windings is coupled to the source of direct current to establish a first portion of the exciter field and wherein the second set of field windings is coupled to the main generator output signals to establish a second portion of the exciter field; and the exciter armature coils include first and second sets of armature windings wherein a first armature current is induced in the first set of armature windings as a result of movement of the exciter rotor in the first portion of the exciter field and wherein a second armature current is induced in the second set of armature windings as a result of movement of the exciter rotor in the second portion of the exciter field, the first and second armature currents being combined to form the exciter output current. An excitation system for a brushless alternator driven by a source of motive power, comprising: a main generator coupled to and supplying power to a load, the main generator having an armature coil, a field coil for establishing a main generator magnetic field in space occupied by the main generator armature coil and means for coupling the main generator to the source of motive power such that the armature coil and the main generator magnetic field move relative to one another to develop main generator output power in the armature coil; an exciter having an exciter field coil connected in series between the main generator armature coil and the load so that the exciter field coil carries the main generator AC output current to establish an alternating exciter magnetic field, an exciter armature coil within the exciter magnetic field, the coupling means also coupling the exciter to the source of motive power such that the exciter magnetic field and the exciter armature coil move relative to one another to develop an exciter output current in the exciter armature coil; and means for connecting the exciter output current to the main generator field coil to establish the main generator magnetic field.