Abstract: A generator system, including first and second generators, a connection circuit connecting output lines of the first and second generators to each other and connecting neutral lines of the first and second generators to the ground, a switch command unit outputting commands to switch a connection mode of the first and second generators between parallel and series connection modes, a circuit switch switching a connection mode of the connection circuit in response to the commands, a data acquiring unit acquiring a waveform data of the first generator when the second generator is operated after the first generator is operated, and a control unit controlling the second generator to synchronize frequency and phase of waveforms of the first and second generators in the parallel connection mode and controlling the second generator to synchronize frequency and shift phase by 180 degree in the series connection mode.

Abstract: An engine generator, including an engine having a piston reciprocating inside a cylinder, a generator unit having a three-phase winding, driven by the engine to generate power and operating as an engine starter motor during engine starting, a power converter circuit connected to the generator unit, a battery supplying power to the generator unit through the power converter circuit during engine starting, an engine speed detection unit detecting an engine speed, a connection switching unit switching a connection configuration of the winding to one of a wye-connection and a delta-connection, and a connection switching control unit controlling the connection switching unit to switch the connection configuration to the wye-connection when the engine speed is lower than a predetermined engine speed, and to switch the connection configuration to the delta-connection when the engine speed is equal to or higher than the predetermined engine speed, during engine starting.

Abstract: An engine generator, including a general purpose engine, an engine speed of the engine being variably controlled, a generator unit having a three-phase winding and driven by the engine to generate power, an inverter unit converting AC output from the generator unit to AC of a predetermined frequency to output to a load, a connection switching unit switching a connection configuration of the winding to one of a wye-connection and a delta-connection, a load detection unit detecting a size of the load, and a connection switching control unit controlling the connection switching unit to switch the connection configuration to the wye-connection when the size of the load is equal to or lower than a predetermined value, and to switch the connection configuration to the delta-connection when the size of the load is higher than the predetermined value.

Abstract: An engine generator, including a general-purpose engine, a generator unit driven by the engine to generate electric power and capable of operating as an engine starter motor during engine starting, a case housing the engine and the generator unit, a battery detachably attached to the case, an inverter unit connected to the generator unit, and a power supply circuit interconnecting the battery attached to the case and the inverter unit and supplying power of the battery through the inverter unit to the generator unit.

Abstract: An engine generator, including a generator unit driven by the engine, a first power converter circuit, a capacitor, a second power converter circuit, a smoothing circuit, battery and a control unit. The control unit controls operation of the switching elements of the second power converter circuit so as to form a boosting circuit by the battery, the coil of the smoothing circuit, the switching element and the diode of the second power converter circuit, and the capacitor at starting of the engine.

Abstract: A power generator system, including a remaining fuel detector detecting a remaining fuel amount of each of the first generator and the second generator, an operable time calculator calculating a remaining operable time of the each of the first generator and the second generator based on the remaining fuel amount detected by the remaining fuel detector, and a signal output unit outputting a control signal for adjusting outputs of the first generator and second generator to an actuator so that the remaining operable time of the first generator and the remaining operable time of the second generator calculated by the operable time calculator is equalized while keeping a total power of the first generator and the second generator constant.

Abstract: A rising temperature of components of an electric generator is restrained without deteriorating the quality of electricity output and the user-friendliness of the electric generator. AVR (7) and a temperature detecting means (75) is provided in a generator housing. While the detected temperature is greater than the limitation starting temperature, the output voltage is decreased by decreasing the control target value (for the AVR (7)) in accordance with the temperature. A range between the power generation stopping temperature as an upper-limit temperature of a generator component and the limitation starting temperature set to be a lower than the power generation stopping temperature is defined as a voltage droop range. In the voltage droop range, the control target value is decreased in accordance with a target voltage base value preset in a relationship with the temperature so that the decrease degree becomes greater in proportion to a rising temperature.

Abstract: In a self-excited generator 1 including an automatic voltage regulator (AVR) 10, a condensive load protection device includes: a field current control driver 21 which is connected to the field winding 6 in series and controlled to be ON/OFF by a drive circuit 23 of the AVR 10 to supply a field current to the field winding 6; and a condensive load protecting rotor short-circuit driver 22 which is connected in parallel to the field winding 6, and supplies a short-circuit current to the field winding 6 by being turned ON, and a bootstrap circuit 30 is connected as a drive power supply of the field current control driver and the condensive load protecting rotor short-circuit driver, and the bootstrap circuit 30 includes a capacitance portion 32 in which charges are accumulated when the field current control driver 21 is ON.

Abstract: A generator (100) includes a generator winding (103) and an excitation winding (104), and a field winding (102). To converge an output voltage of the generator winding (103) to a target, a field current is varied by increasing/decreasing an energization duty ratio of a switching device (110) connected to the field winding (102). In a duty ratio zero determination unit (2) and a duty ratio zero continuation determination unit (3), when an output duty ratio continues for a predetermined time with duty ratio zero, a duty ratio increase amount restriction unit (4) restricts an upper limit of the duty ratio to a predetermined upper limit when the field current increases. A duty ratio restriction unit (21a) for restricting the duty ratio by a maximum value determined based on a voltage of a smoothing capacitor (113) in place of the determination of the duty ratio being zero may be provided.

Abstract: When a distortion of an output waveform of an alternating-current generator is improved, an output voltage control apparatus of a generator, which has versatility, is obtained. An output voltage control apparatus of a generator (1), including a generator winding (2) and an excitation winding (3) wound around a stator side, a field winding (5) wound around a rotor (4), and a rectifier (12) for rectifying a current generated by the excitation winding (3) and supplying the rectified current to the field winding (5), the output voltage control apparatus includes a field current drive means (20) for comparing an output voltage generated to the generator winding (2) with a reference wave whose distortion ratio is 0% and flowing a field current to the field winding (5) by adjusting a drive timing of a PWM signal output by a drive unit (24) based on a result of the comparison.

Abstract: A rising temperature of components of an electric generator is restrained without deteriorating the quality of electricity output and the user-friendliness of the electric generator. AVR (7) and a temperature detecting means (75) is provided in a generator housing. While the detected temperature is greater than the limitation starting temperature, the output voltage is decreased by decreasing the control target value (for the AVR (7)) in accordance with the temperature. A range between the power generation stopping temperature as an upper-limit temperature of a generator component and the limitation starting temperature set to be a lower than the power generation stopping temperature is defined as a voltage droop range. In the voltage droop range, the control target value is decreased in accordance with a target voltage base value preset in a relationship with the temperature so that the decrease degree becomes greater in proportion to a rising temperature.

Abstract: In a self-excited generator 1 including an automatic voltage regulator (AVR) 10, a condensive load protection device includes: a field current control driver 21 which is connected to the field winding 6 in series and controlled to be ON/OFF by a drive circuit 23 of the AVR 10 to supply a field current to the field winding 6; and a condensive load protecting rotor short-circuit driver 22 which is connected in parallel to the field winding 6, and supplies a short-circuit current to the field winding 6 by being turned ON, and a bootstrap circuit 30 is connected as a drive power supply of the field current control driver and the condensive load protecting rotor short-circuit driver, and the bootstrap circuit 30 includes a capacitance portion 32 in which charges are accumulated when the field current control driver 21 is ON.

Abstract: When a distortion of an output waveform of an alternating-current generator is improved, an output voltage control apparatus of a generator, which has versatility, is obtained. An output voltage control apparatus of a generator (1), including a generator winding (2) and an excitation winding (3) wound around a stator side, a field winding (5) wound around a rotor (4), and a rectifier (12) for rectifying a current generated by the excitation winding (3) and supplying the rectified current to the field winding (5), the output voltage control apparatus includes a field current drive means (20) for comparing an output voltage generated to the generator winding (2) with a reference wave whose distortion ratio is 0% and flowing a field current to the field winding (5) by adjusting a drive timing of a PWM signal output by a drive unit (24) based on a result of the comparison.

Abstract: A generator (100) includes a generator winding (103) and an excitation winding (104), and a field winding (102). To converge an output voltage of the generator winding (103) to a target, a field current is varied by increasing/decreasing an energization duty ratio of a switching device (110) connected to the field winding (102). In a duty ratio zero determination unit (2) and a duty ratio zero continuation determination unit (3), when an output duty ratio continues for a predetermined time with duty ratio zero, a duty ratio increase amount restriction unit (4) restricts an upper limit of the duty ratio to a predetermined upper limit when the field current increases. A duty ratio restriction unit (21a) for restricting the duty ratio by a maximum value determined based on a voltage of a smoothing capacitor (113) in place of the determination of the duty ratio being zero may be provided.