Abstract: A semiconductor device includes: a gate electrode including a junction portion forming a Schottky junction with a barrier layer; a projecting portion including first and second gate field plates and projecting from the junction portion; and an insulating layer including first and second sidewalls. An angle formed between a highest position of a bottom surface of the first gate field plate and a main surface of a substrate, viewed from the first position, is a second elevation angle. An angle formed between an end on the drain electrode side of a lowest portion of a bottom surface of the second gate field plate and the main surface, viewed from the first position, is a third elevation angle. The second elevation angle is larger than the third elevation angle. The bottom surface of the second gate field plate includes an inclined surface where a distance from the barrier layer monotonically increases.

Abstract: An AC motor drive motor system includes a charge and discharge controller controlling a charging and discharging circuit based on a DC voltage value on the output side of a converter and a charging and discharging current value of a power storage device. The charge and discharge controller, when regenerative power via an inverter from an AC motor exceeds a power threshold, charges the power storage device such that the DC voltage value becomes a voltage threshold corresponding to the power threshold. When regenerative power is the power threshold or less, the converter performs regeneration when the DC voltage value reaches a regeneration start voltage threshold or higher, and ends regeneration when the DC voltage value reaches a regeneration end voltage threshold or lower. The DC-voltage-value time averaged value during regeneration is set lower than that at no-load time when the converter does not perform power supply and regeneration.

Abstract: An AC motor drive motor system includes a charge and discharge controller controlling a charging and discharging circuit based on a DC voltage value on the output side of a converter and a charging and discharging current value of a power storage device. The charge and discharge controller, when regenerative power via an inverter from an AC motor exceeds a power threshold, charges the power storage device such that the DC voltage value becomes a voltage threshold corresponding to the power threshold. When regenerative power is the power threshold or less, the converter performs regeneration when the DC voltage value reaches a regeneration start voltage threshold or higher, and ends regeneration when the DC voltage value reaches a regeneration end voltage threshold or lower. The DC-voltage-value time averaged value during regeneration is set lower than that at no-load time when the converter does not perform power supply and regeneration.

Abstract: When regenerative power from an AC motor via an inverter exceeds a predetermined power threshold, a charging/discharging control unit, which outputs a control signal for controlling the inverter on the basis of a DC bus voltage value and a charging/discharging current value, causes a power storage device to be charged such that the DC bus voltage value becomes a voltage threshold corresponding to the power threshold and causes a charging current at a start time of charging to the power storage device to start from a charging current value that is based on a DC bus voltage value.

Abstract: When regenerative power from an AC motor via an inverter exceeds a predetermined power threshold, a charging/discharging control unit, which outputs a control signal for controlling the inverter on the basis of a DC bus voltage value and a charging/discharging current value, causes a power storage device to be charged such that the DC bus voltage value becomes a voltage threshold corresponding to the power threshold and causes a charging current at a start time of charging to the power storage device to start from a charging current value that is based on a DC bus voltage value.

Abstract: An energy assist system selection supporting apparatus equipped with a step-up/step-down chopper unit, an electricity storage unit, and an electric motor configured to drive a machine includes an operation-pattern generating section for generating an operation pattern taking into account an electronic machine configuration, a load-pattern generating section for generating a load pattern concerning power consumption according to the generated operation pattern, a data processing section for evaluating, according to the generated load pattern, a characteristic of the energy assist system applied with the generated operation pattern while comparing the characteristic with a limit value and generate, according to an evaluation result, configuration information including the number of each unit of the energy assist system, and a layout section configured to lay out and arrange the units on a virtual space and display the units on a display screen according to the generated configuration information.

Abstract: An alternating current (AC) motor drive system is provided in which electric power can be supplied between a direct current (DC) bus and an electric power storage device, using a voltage value across a DC bus, without providing means that measures an amount of current flowing through the DC bus. In the AC motor drive system of the invention, according to a voltage value measured by DC voltage value detection means and a charge/discharge current amount measured by charge/discharge current amount detection means, a charge/discharge circuit causes an electric power storage device to discharge an amount of electric power, from among amounts of electric power supplied from an inverter to an AC motor, that exceeds a first electric power threshold value, or the circuit causes the electric storage device to store an amount of electric power, from among amounts of AC motor regenerative electric power regenerated via the inverter, that exceeds a second electric power threshold value.

Abstract: During initial charging for forming a predetermined bus voltage in a direct-current bus performed in a converter circuit when power is supplied to a motor control apparatus to which a power storage apparatus is connected, a step-down switching element in a step-up/down chopper circuit in the power storage apparatus is caused to perform ON/OFF operations a predetermined times to apply the initial charging to a power storage device, actual capacitance of the power storage device is calculated from total energy given to the power storage device in a period of the ON/OFF operations performed the predetermined times and a charging voltage indicated by the power storage device, and the calculated actual capacitance and initial capacitance of the power storage device are compared to estimate a deterioration degree of the power storage device and diagnose the life of the power storage device.

Abstract: An energy assist system selection supporting apparatus is an energy assist system selection supporting apparatus that supports selection of an energy assist system including a step-up/step-down chopper unit, an electricity storage unit, and an electric motor and configured to drive a machine.

Abstract: A first period during which drain is not substantially generated on a surface of a water tube (4) of a heat exchanger (B1), and a second period as a transition during which an amount of drain on the surface of the water tube (4) is increased are provided. There are a plurality of kinds of fan-controlling data in which operation control contents of the fan (13) in the first and second periods in correspondence with change of conditions of entering water temperature or combustion level of the burner (1). The fan-controlling data are stored in a data table (90) of a controller (9). The controller (9) controls the fan (13) in accordance with the data, and an initial air-fuel ratio of combustion driving of the burner (1) is stabilized.

Abstract: There is provided a clock generator for generating a modulation waveform which is high in the effect of suppressing a spectrum and making a circuit scale smaller than a modulation system using the Hershey-kiss waveform. More specifically, a modulation waveform generation unit generates a tangent waveform or a tangent+triangular waveform as an SSCG modulation waveform and provides an oscillator with a signal in which the SSCG modulation waveform is combined with the output of a low pass filter of a PLL loop.

Abstract: A combustion apparatus 51 includes a plurality of burners 58, a plurality of fuel supply channels 89, a blower 53, an air supply passage 37, and a pressure regulator 56. The burners 58 are divided into a plurality of burner groups 71. The pressure regulator 56 is branched at a portion located immediately after a gas outlet 31 at downstream of the regulator 56 and connected to the respective fuel supply channels 89, so as to regulate gas supplied at a primary pressure to gas at a secondary pressure in response to a predetermined signal pressure sensed from one selected from a part of the air supply passage 37 and the blower 53 and to discharge the regulated gas through the pressure regulator 56. The fuel supply channels 89 each are configured to perform fuel supply to the respective burner groups 71 and are provided with a switching valve 75 for either shutting off or reducing the fuel supply to at least a part of the burner groups 71.

Abstract: There is provided a clock generator for generating a modulation waveform which is high in the effect of suppressing a spectrum and making a circuit scale smaller than a modulation system using the Hershey-kiss waveform. More specifically, a modulation waveform generation unit generates a tangent waveform or a tangent+triangular waveform as an SSCG modulation waveform and provides an oscillator with a signal in which the SSCG modulation waveform is combined with the output of a low pass filter of a PLL loop.

Abstract: A spread spectrum clock generator includes a voltage-controlled oscillator generating an operation clock, a feedback control unit, a modulated pulse generation unit generating a pulse signal obtained by performing a delta-sigma modulation on a component fluctuating a frequency of the operation clock, a level set unit setting an amplitude of the pulse signal, an adder adding a voltage generated by the feedback control unit and the pulse signal whose amplitude is set by the level set unit, and a low pass filter filtering a signal outputted from the adder and generating a control voltage applied to the voltage-controlled oscillator. The feedback control unit compares a phase of the operation clock with a phase of a reference clock, and based on results of the comparison, generates a voltage used as a reference to oscillate the voltage-controlled oscillator.

Abstract: There is provided a clock generator for generating a modulation waveform which is high in the effect of suppressing a spectrum and making a circuit scale smaller than a modulation system using the Hershey-kiss waveform. More specifically, a modulation waveform generation unit generates a tangent waveform or a tangent+triangular waveform as an SSCG modulation waveform and provides an oscillator with a signal in which the SSCG modulation waveform is combined with the output of a low pass filter of a PLL loop.

Abstract: A combustion apparatus mainly consists of burners, a fuel supply channel having branched channels, an air feeder for supplying air to the burners, and a pressure regulator and has a combustion space. The branched channels allow fuel gas supplied to the burners to pass therethrough and are provided with shutoff valves. The pressure regulator includes a signal-pressure inlet and a secondary-pressure inlet. A signal pressure introduced through the signal-pressure inlet is detected at a downstream of the air feeder and a secondary pressure introduced through the secondary-pressure inlet is detected at a vicinity of a boundary of the branched channels in the fuel supply channel. Fuel gas discharged from the pressure regulator is regulated so as to satisfy a predetermined relationship between the signal pressure introduced through the signal-pressure inlet and the secondary pressure introduced through the secondary-pressure inlet.

Abstract: A spread spectrum clock generator includes a voltage-controlled oscillator generating an operation clock, a feedback control unit, a modulated pulse generation unit generating a pulse signal obtained by performing a delta-sigma modulation on a component fluctuating a frequency of the operation clock, a level set unit setting an amplitude of the pulse signal, an adder adding a voltage generated by the feedback control unit and the pulse signal whose amplitude is set by the level set unit, and a low pass filter filtering a signal outputted from the adder and generating a control voltage applied to the voltage-controlled oscillator. The feedback control unit compares a phase of the operation clock with a phase of a reference clock, and based on results of the comparison, generates a voltage used as a reference to oscillate the voltage-controlled oscillator.

Abstract: A combustion apparatus 51 includes a plurality of burners 58, a plurality of fuel supply channels 89, a blower 53, an air supply passage 37, and a pressure regulator 56. The burners 58 are divided into a plurality of burner groups 71. The pressure regulator 56 is branched at a portion located immediately after a gas outlet 31 at downstream of the regulator 56 and connected to the respective fuel supply channels 89, so as to regulate gas supplied at a primary pressure to gas at a secondary pressure in response to a predetermined signal pressure sensed from one selected from a part of the air supply passage 37 and the blower 53 and to discharge the regulated gas through the pressure regulator 56. The fuel supply channels 89 each are configured to perform fuel supply to the respective burner groups 71 and are provided with a switching valve 75 for either shutting off or reducing the fuel supply to at least a part of the burner groups 71.

Abstract: A first period during which drain is not substantially generated on a surface of a water tube (4) of a heat exchanger (B1), and a second period as a transition during which an amount of drain on the surface of the water tube (4) is increased are provided. There are a plurality of kinds of fan-controlling data in which operation control contents of the fan (13) in the first and second periods in correspondence with change of conditions of entering water temperature or combustion level of the burner (1). The fan-controlling data are stored in a data table (90) of a controller (9). The controller (9) controls the fan (13) in accordance with the data, and an initial air-fuel ratio of combustion driving of the burner (1) is stabilized.

Abstract: A combustion apparatus 2 has a fuel spraying nozzle 12, a feed canal 16 and a return canal 17, both the canals connected to the nozzle, with the former canal 16 feeding a fuel to the nozzle and with the latter canal 17 allowing an unsprayed portion of the fuel to flow back. An electromagnetic pump 18 disposed in the feed canal 16 serves to compress the fuel towards the nozzle 12, and an injector valve 25 is disposed in the return canal 17. A controller 40 regulates the operation of the injector valve 25 in the manner of duty-ratio control so as to adjust the flow rate of the fuel being sprayed out of the nozzle 12.