Abstract: A motor temperature estimation system includes a first temperature time series data generation unit that generates first temperature time series data based on temperature data acquired by a temperature sensor that measures a temperature of a motor, a resistance value time series data generation unit that generates resistance value time series data based on the first temperature time series data, a second temperature time series data generation unit that generates second temperature time series data by changing parameters for estimating and calculating the temperature of the motor based on the resistance value time series data, and a parameter determination unit that determines the parameters by comparing the first temperature time series data and the second temperature time series data.

Abstract: A motor control apparatus includes an inverter comprising switching elements, current detection means for detecting a phase current value output from the inverter to each phase of a three-phase AC motor, conversion means for converting the phase current value into a digital AD conversion value, and modulation means for comparing a phase voltage command value based on the AD conversion value from the conversion means with a PWM counter value generated using a timer operating at predetermined cycles to generate a PWM signal and outputting the generated PWM signal to the inverter to thereby switch the switching elements of the inverter and control the three-phase AC motor. The conversion means outputs the AD conversion value acquired by converting the phase current value at a timing when a rectangular width of a rectangular wave of a phase voltage value corresponding to the PWM counter value is long.

Abstract: A motor control apparatus includes a current estimation unit configured to output a detected current value corresponding to each of the three-phase AC currents based on the measured current value and rotor rotation angle information of the motor. The current estimation unit defines a phase whose duty ratio of a driving pulse supplied to an inverter circuit, which generates the three-phase AC currents, becomes more than or equal to an operation switching threshold as an estimation target phase, calculates, for the estimation target phase, an estimated current value based on a coefficient value, which is calculated from the measured current value by the current measurement unit in a period in which the duty ratio of the driving pulse is lower than the operation switching threshold, and the rotor rotation angle information, and outputs the calculated estimated current value as the detected current value of the estimation target phase.

Abstract: A motor control apparatus includes an inverter comprising switching elements, current detection means for detecting a phase current value output from the inverter to each phase of a three-phase AC motor, conversion means for converting the phase current value into a digital AD conversion value, and modulation means for comparing a phase voltage command value based on the AD conversion value from the conversion means with a PWM counter value generated using a timer operating at predetermined cycles to generate a PWM signal and outputting the generated PWM signal to the inverter to thereby switch the switching elements of the inverter and control the three-phase AC motor. The conversion means outputs the AD conversion value acquired by converting the phase current value at a timing when a rectangular width of a rectangular wave of a phase voltage value corresponding to the PWM counter value is long.

Abstract: A motor control apparatus includes a current estimation unit configured to output a detected current value corresponding to each of the three-phase AC currents based on the measured current value and rotor rotation angle information of the motor. The current estimation unit defines a phase whose duty ratio of a driving pulse supplied to an inverter circuit, which generates the three-phase AC currents, becomes more than or equal to an operation switching threshold as an estimation target phase, calculates, for the estimation target phase, an estimated current value based on a coefficient value, which is calculated from the measured current value by the current measurement unit in a period in which the duty ratio of the driving pulse is lower than the operation switching threshold, and the rotor rotation angle information, and outputs the calculated estimated current value as the detected current value of the estimation target phase.

Abstract: A motor driving device includes: an inverter control unit configured to generate and output a control signal for feedback-controlling a motor using a control command value for setting driving of the motor and a feedback value including a current value of driving power supplied to the motor; an inverter configured to supply driving power to the motor in accordance with the control signal output from the inverter control unit; and an abnormality detecting unit configured to detect an abnormality of the inverter. The abnormality detecting unit determines that the inverter is abnormal when a sum of three-phase AC voltage values of the driving power supplied to the motor is greater than a predetermined voltage value and a difference between the control command value supplied to the inverter control unit and the feedback value is less than a predetermined value.

Abstract: A motor driving device includes: an inverter control unit configured to generate and output a control signal for feedback-controlling a motor using a control command value for setting driving of the motor and a feedback value including a current value of driving power supplied to the motor; an inverter configured to supply driving power to the motor in accordance with the control signal output from the inverter control unit; and an abnormality detecting unit configured to detect an abnormality of the inverter. The abnormality detecting unit determines that the inverter is abnormal when a sum of three-phase AC voltage values of the driving power supplied to the motor is greater than a predetermined voltage value and a difference between the control command value supplied to the inverter control unit and the feedback value is less than a predetermined value.

Abstract: A stripline patch antenna having a slot plate which is capable of obtaining higher antenna gain, while reducing the loss due to the feed lines. The antenna includes at least one radiating element for transmitting and receiving radio waves; a feed line for transmitting signals to and from the radiating element; a dielectric substrate for supporting the radiating element means and the feed line means; a grounding conductor located below the dielectric substrate; and a slot plate located above the dielectric substrate, having a plurality of slots more numerous than the radiating element. The triplate substrate can be adapted to this antenna. A plurality of antenna units so constructed can be arranged in array such that at least one of the slots of each antenna unit is shared with a neighboring antenna unit.

Abstract: Disclosed is a discharge lamp lighting device which comprises a series closed-loop circuit including an AC power supply, a ballast having an inductance, and a discharge lamp, and a switch circuit in parallel to the discharge lamp. The switch circuit is turned on when the voltage across the discharge lamp is reduced to zero, and then turned off when the current flowing in the switch reaches a predetermined value. The switch circuit thus repeats its on-off operation every half cycle of the voltage across the discharge lamp. The electromagnetic energy is stored in the inductance of the ballast when the switch circuit is on, and the stored electromagnetic energy is superimposed on the source voltage and applied to the discharge lamp when the switch circuit is turned off, thus reigniting the discharge lamp every half cycle. This makes it possible to light directly a discharge lamp having a lamp voltage approximate to the source voltage.

Abstract: A discharge lamp lighting device comprises a serial connection of an inductive ballast and a discharge lamp connected across an A.C. power source, and a switching circuit connected substantially in parallel to the discharge lamp and operable to carry out two consecutive ON/OFF operations in the beginning of each half cycle of the A.C. power source while the discharge lamp is in its lit condition. The switching circuit preferably comprises a full-wave rectifier connected substantially in parallel to the discharge lamp, a switching element connected between the output terminals of the rectifier, and a control circuit for controlling the ON/OFF operation of the switching element.

Abstract: A starter for a discharge lamp including first and second filaments, comprises an SCR having an anode and a cathode connected in series through the first and second filaments and a ballast transformer to an AC power supply. The gate electrode and the anode of the SCR are connected to each other through a first resistor, while the gate electrode is further connected through a second resistor to the power supply side.

Abstract: A voltage producing device comprises a circuit in which an AC power source, a coil and a first capacitor connected in series. A unidirectional triode semiconductor switching element is connected across both terminals of the capacitor, a voltage limiting semiconductor element is connected to a gate electrode of the switching element, and a charging-and-discharging circuit including a second capacitor is connected to a cathode of the switching element.

Abstract: A solid state starter apparatus for a discharge lamp comprises a current limiter, an AC power supply, a discharge lamp of filament-preheating type and a switching circuit for controlling the turning on and off of the discharge lamp. The switching circuit further includes a lightedstate detector circuit for detecting the turning on or off of the discharge lamp, a current breaker circuit controlled by the lighted-state detector circuit to cause the filament current to be turned on and off, and a preheater circuit for starting to supply a filament preheating current in accordance with the magnitude of the current controlled by the current breaker circuit.

Abstract: An electric discharge lamp lighting circuit in which a discharge lamp is lighted by a circuit comprising a semiconductor switching circuit in which the cathode of a first thyristor is connected to the gate of a second thyristor and the first and second thyristors are commonly connected at the respective anodes, an integration circuit consisting of a capacitor and a resistor and connected between the gate of the first thyristor and the cathode of the second thyristor, a resistor connected between the integration circuit and the anode of the first thyristor, and a resistor connected between the gate and cathode of the second thyristor.