The present disclosure provides a wind power generation system, which comprises a wind turbine for generating mechanical energy; a generator for converting the mechanical energy into electrical energy; a converter for converting the electrical energy to expected power for supplying to a grid, wherein a rotor of the generator is connected to converter, an output of a stator of the generator and an output of a converter are both connected to the grid; a controller for controlling the converter to absorb rotor-side reactive power Q.sub.rotor and to increase line-side reactive power Q.sub.line, so as to meet a reactive power demand of the grid, when a rotor speed is less than a predetermined value.

A power generating apparatus is provided. The alternator includes a rotor, a stator, one or more sensors and an electrical circuit. The rotor includes a plurality of symmetric phase windings while the stator has a single phase winding. The excitation control device is configured to control the induced voltage generated in the stator by regulating the rotating magnetic field generated in the phase windings of the rotor. The excitation control device is also configured to regulate the engine speed responsive to calculated load power. The electrical circuit connects the single phase winding of the stator and the load and is configured in a way that the induced voltage generated in the single phase winding and the output voltage applied to the load are at the same frequency. This arrangement reduces costs of the apparatus.

A power generating apparatus is provided. The alternator includes a rotor, a stator, one or more sensors and an electrical circuit. The rotor includes a plurality of symmetric phase windings while the stator has a single phase winding. The excitation control device is configured to control the induced voltage generated in stator by regulating the rotating magnetic field generated in the phase windings of the rotor. The excitation control device is also configured to regulate the engine speed responsive to calculated load power. The electrical circuit connecting the single phase winding of the stator and the load is configured in a way that the induced voltage generated in the single phase winding and the output voltage applied to the load are at the same frequency. This arrangement reduces costs of the apparatus.

A power generating apparatus and vector control method thereof are provided. The apparatus includes a rotor with plurality of symmetric phase windings, a stator with a single phase winding, sensors and an excitation control device. Current sensors on the stator side and on the rotor side are configured to measure the amplitudes of the load current and the phase current of the rotor respectively. A position sensor is configured to measure the angle of the rotor. The excitation control device is configured to regulate the engine speed responsive to load power. The excitation control device also generates a modulating signal in accordance with the target voltage vector of the rotor and the slip angle and regulates the excitation current in the phase windings of the stator with the modulating signal.

An off-grid power generating apparatus is provided. The apparatus includes an engine, an alternator and an excitation control device. The alternator includes a rotor, a switch and a stator. The switch is movable between a first position and a second position. An output portion of the stator has first and second segments each of which has at least one coil. The first and second segments are operatively and separately connected with the switch. The first and second segments are connected in series at the first position and in parallel at the second position to provide a high voltage and a low voltage respectively. The excitation control device controls the output voltage to make it have a predetermined frequency, and to regulate the engine speed in response to the load power of the engine.

Systems and methods for protecting a generator are provided. An example method can include receiving a signal indicative of a voltage associated with a stator. The method can include receiving a signal indicative of a nominal voltage associated with the stator. The method can include receiving a signal indicative of a monitoring state associated with the generator. The method can include receiving a signal indicative of a deadband range. The method can include determining a voltage ratio based at least in part on the voltage associated with the stator and the nominal voltage. The method can include determining an adjusted operating limit using a multiplier determined based at least in part on the voltage ratio. The method can include generating a power command to control operation of the generator based at least in part on the adjusted operating limit.

A direct-current (DC) power generation system for a vehicle, a boosting shunt regulator, and a method of regulating the output of an AC generator with the boosting shunt regulator are provided. The boosting shunt regulator includes gated power switches electrically coupled between AC generator contacts and output contacts. A shunt operates the power switches at duty cycles selected to boost the AC voltages output by the AC generator.

The apparatus employs magnetoresistive sensors (28) to generate a sinusoid having a time-varying instantaneous frequency commensurate with the instantaneous frequency of the angular displacement of a motor's rotating shaft (40). The resultant signal is then fed to a mixture of fixed-phase-shifting circuits (22) whose outputs are then amplified by voltage-controlled amplifiers and fed to independently wired stator phases (56).

A voltage monitoring system having a microcontroller with an analog-to-digital converter with a first channel, and a memory device is provided. The microcontroller includes a monitoring application and a hardware abstraction layer. The monitoring application sends a first encoded channel number to the hardware abstraction layer. The hardware abstraction layer determines a first channel number based on the first encoded channel number, and obtains a measured voltage value associated with the first channel number. The hardware abstraction layer sends a second encoded channel number and the measured voltage value therein to the monitoring application. If the first encoded channel number is equal to the second encoded channel number, then the monitoring application stores the measured voltage value in the memory device.

An isolated bus inverter system including inverter circuits and a controller. The inverter circuits include a switching array to provide a polyphase alternating current (AC) signal to an output. Each of the inverter circuits includes an energy source isolated from the other inverter circuits of the inverter circuits or a reference isolated from the other inverter circuits of the inverter circuits. The controller is configured to generate timing signals for the inverter circuits to generate the AC signals for the output based on DC signals received from one or more rectifier circuits.