In an assembly for electrically exciting the rotor of an electrical machine, the wear of the sliding contacts is reduced in operating conditions with low current density in that an AC current is injected. The additional injection of the AC current is superimposed upon the DC current. The rotor poles function as an open circuit with respect to the AC current through a co-rotating capacitor.

In an assembly for electrically exciting the rotor of an electrical machine, the wear of the sliding contacts is reduced in operating conditions with low current density in that an AC current is injected. The additional injection of the AC current is superimposed upon the DC current. The rotor poles function as an open circuit with respect to the AC current through a co-rotating capacitor.

A thyristor starter is configured to accelerate a synchronous machine from a stop state to a predetermined rotation speed by sequentially performing a first mode of performing commutation of an inverter by intermittently setting DC output current of a converter to zero and a second mode of performing commutation of the inverter by induced voltage of the synchronous machine. The thyristor starter is further configured to raise induced voltage in proportion to the rotation speed of the synchronous machine by keeping field current constant and to suppress rise of the induced voltage by reducing the field current after the induced voltage reaches a first voltage value, in the first mode.

A field coil type rotating electric machine includes a rotor where both a series resonant circuit including a first winding and a capacitor and a parallel resonant circuit including a second winding and the capacitor are formed. The first winding is radially located closer than the second winding to a stator. The capacitance of the capacitor and the ratio of the number of turns of the second winding to the number of turns of the first winding are set to have the amplitude of a total resultant magnetic flux lower than the amplitude of a field resultant magnetic flux. The total resultant magnetic flux is the resultant of the field resultant magnetic flux and magnetic flux generated by harmonic currents flowing in phase windings of a stator coil. The field resultant magnetic flux is the resultant of magnetic fluxes generated by harmonic currents flowing in the first and second windings.

A system for load balancing on a multi-phase power line connected to a single phase lateral power line, includes a contactor configured to selectively connect each phase of the multi-phase power line to the single phase lateral power line. There is a phase change device connected in parallel with the contactor and a controller. During the phase change state, the controller connects the input of the phase change device to the multi-phase power line and connects the output of the phase change device the single phase lateral power line. The controller causes the phase change device to output a voltage to the single phase lateral line initially aligned with the first phase and then rotated to align with the second phase and causes the contactor changes connection to the second phase of the multi-phase power line and disconnect the phase change device from the power lines.

A system for load balancing on a multi-phase power line connected to a single phase lateral power line, includes a contactor configured to selectively connect each phase of the multi-phase power line to the single phase lateral power line. There is a phase change device connected in parallel with the contactor and a controller. During the phase change state, the controller connects the input of the phase change device to the multi-phase power line and connects the output of the phase change device the single phase lateral power line. The controller causes the phase change device to output a voltage to the single phase lateral line initially aligned with the first phase and then rotated to align with the second phase and causes the contactor changes connection to the second phase of the multi-phase power line and disconnect the phase change device from the power lines.

A de-exciting system for dissipating energy from an inductive circuit that comprises at least one coil adapted to be attached to said inductive circuit and comprising a series connection of a discharge resistor and a unidirectional discharge switching element; a unidirectional bypass switching element that is connected in parallel to the discharge resistor such that, when the de-exciting system is attached to the inductive circuit and both the discharge switching element and the bypass switching element are in a conducting state, a closed conducting path comprising the coil, the discharge switching element, and the bypass switching element is formed; and a control device configured to, in a first de-excitation phase, switch both the discharge switching element and the bypass switching element into a conducting state, and in a second de-excitation phase, switch the bypass switching element into a non-conducting state, while keeping the discharge switching element in the conducting state.

The present inventions include a rotating electromagnetic machine such as a motor or generator wherein changes of flux direction adjacent the air gap are avoided. The disclosed improvements apply to permanent magnet alternators, induction motors and generators, doubly fed induction generators, and the like. Adaptation of coils to and fixation within the required slot geometries are disclosed. Excitation systems co-located within the primary rotor core and primary stator core are also disclosed. The use of rubber vulcanized to the rotor in conjunction with a stainless steel rotor sleeve is also disclosed.

A rotating electrical machine of a brushless wound field type disposed between a stationary case and rotating member that rotates inside the case includes a stator held by the case, including an AC coil that generates a rotating magnetic field with an alternating current, a field core held by the case, the field core including a field coil that generates a magnetic flux with a direct current, a rotor fixed in contact with an outer circumferential surface of the rotating member and held rotatably relative to the stator and field coil, a rotor side core portion that is a part of the rotating member. The magnetic flux of the field coil passes from the field core through the rotor via the second air gap, the stator and rotor via the first air gap, the rotor side core portion, and the field core via the third air gap.

A brushless winding field rotational electric machine positioned between a starting device and a case enclosing the starting device includes: a stator, which is held to the case, including an alternating-current coil configured to generate a rotation magnetic field by alternating current; a field core, which is held to the case, including a field coil to be excited by direct current; and a rotor disposed on an outer periphery of the starting device and rotatably held about a rotational axis relative to the stator and the field coil. The rotor includes a connection portion to be connected to a synchronized rotation member configured to rotate in synchronization with an engine along the rotational axis, on a facing surface to the synchronized rotation member.