A high voltage power generating system includes a first poly-phase permanent magnet generator including at least one control winding and a plurality of power windings, a second poly-phase permanent magnet generator including at least one control winding and a plurality of power windings, the first and second poly-phase permanent magnet generators being arranged in series in at least one operational mode, and the first poly-phase permanent magnet generator being phase shifted relative to the second poly-phase permanent magnet generator such that residual voltage output of the first poly-phase permanent magnet generator is offset by the second poly-phase permanent magnet generator during a first operational mode.

A voltage difference is determined between the observed voltage and a reference direct current bus voltage. A quadrature-axis (q-axis) voltage command is outputted based on a current difference derived from the voltage difference. A commanded direct-axis (d-axis) voltage is determined based on a measured d-axis current and a determined d-axis reference current derived from a mathematical relationship between d-axis residual voltage, the observed voltage and the commanded q-axis voltage, where residual voltage is proportional to a function of the observed voltage and the commanded q-axis voltage. An inverse Parks transformation module or a data processor provides one or more phase voltage command based on inverse Parks transform of the commanded voltages.

A voltage difference is determined between the observed voltage and a reference direct current bus voltage. A quadrature-axis (q-axis) voltage command is outputted based on a current difference derived from the voltage difference. A commanded direct-axis (d-axis) voltage is determined based on a measured d-axis current and a determined d-axis reference current derived from a mathematical relationship between d-axis residual voltage, the observed voltage and the commanded q-axis voltage, where residual voltage is proportional to a function of the observed voltage and the commanded q-axis voltage. An inverse Parks transformation module or a data processor provides one or more phase voltage command based on inverse Parks transform of the commanded voltages.

A master generator is configured to use a duty upper limit value and a duty lower limit value to perform duty restriction processing on a PWM signal in continuous Y cycles out of generated X cycles, and transmit the PWM signal after the restriction processing to a slave generator. The slave generator is configured to receive the PWM signal after the restriction processing transmitted from the master generator as a received PWM signal, and determine that a reception abnormality exists when the received PWM signal is received as a signal representing a duty less than the duty lower limit value or a duty more than the duty upper limit value in continuous (X−Y+1) cycles.

A master generator is configured to use a duty upper limit value and a duty lower limit value to perform duty restriction processing on a PWM signal in continuous Y cycles out of generated X cycles, and transmit the PWM signal after the restriction processing to a slave generator. The slave generator is configured to receive the PWM signal after the restriction processing transmitted from the master generator as a received PWM signal, and determine that a reception abnormality exists when the received PWM signal is received as a signal representing a duty less than the duty lower limit value or a duty more than the duty upper limit value in continuous (X−Y+1) cycles.

A secondary magnetic excitation generator-motor device that inputs a first ignition pulse command to a three-level NPC power converter such that a detected excitation current value corresponds with an excitation current command value, the secondary magnetic excitation generator-motor device having a function of identifying a first phase, a second phase, or a third phase in descending order of a current absolute value, wherein a pulse switch to output an ignition pulse command to the three-level NPC power converter switches the ignition pulse command to the second ignition pulse command when a current absolute value exceeds a set overcurrent level 1, and switches the ignition pulse command to the first ignition pulse command when current absolute values for three phases are all equal to or smaller than a set overcurrent level 2.

A secondary magnetic excitation generator-motor device that inputs a first ignition pulse command to a three-level NPC power converter such that a detected excitation current value corresponds with an excitation current command value, the secondary magnetic excitation generator-motor device having a function of identifying a first phase, a second phase, or a third phase in descending order of a current absolute value, wherein a pulse switch to output an ignition pulse command to the three-level NPC power converter switches the ignition pulse command to the second ignition pulse command when a current absolute value exceeds a set overcurrent level 1, and switches the ignition pulse command to the first ignition pulse command when current absolute values for three phases are all equal to or smaller than a set overcurrent level 2.

An electromagnetic induction power generator includes: a current transformer attached to a power transmission line; a rectifier circuit for rectifying an AC voltage output from the current transformer; and a regulator circuit for regulating a DC voltage output from the rectifier circuit. The current transformer has a magnetic core attached to the power transmission line serving as a primary winding and a secondary winding magnetically coupled to the power transmission line through the magnetic core. The magnetic core is configured to start to be magnetically saturated around the minimum value within the fluctuation range of a current flowing through the power transmission line.

An electromagnetic induction power generator includes: a current transformer attached to a power transmission line; a rectifier circuit for rectifying an AC voltage output from the current transformer; and a regulator circuit for regulating a DC voltage output from the rectifier circuit. The current transformer has a magnetic core attached to the power transmission line serving as a primary winding and a secondary winding magnetically coupled to the power transmission line through the magnetic core. The magnetic core is configured to start to be magnetically saturated around the minimum value within the fluctuation range of a current flowing through the power transmission line.

An alternator for generating electrical power to one or more components of a power network includes a machine portion including a stator, a rotor and a rectifier, a battery connection terminal connected to the machine portion and configured to be connected to a battery, and an isolation device integral to the alternator. The isolation device is located on an electrical path between at least the machine portion and the battery connection terminal, and the isolation device is configured to isolate at least one of the alternator and another component of the power network from receiving electric current from the battery based on an undesirable condition occurring in the power network.