Abstract: In a motor control apparatus of the present invention, a control section which receives an input voltage to an inverter circuit, a motor current flowing to a brushless motor and a motor current command value indicating the value of a current required to flow to the inverter circuit, and controls the inverter circuit by maintaining a phase of the voltage applied to the brushless motor when the value of the input voltage to the inverter circuit is smaller than the value of a voltage required to be applied to the brushless motor.

Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device generates PN voltage correction coefficient by dividing the reference DC voltage by the detected DC voltage, and corrects the voltage command of each phase by multiplying the voltage command of each phase obtained by the motor voltage command generator with the PN voltage correction coefficient output from the PN voltage corrector, thus resulting in the corrected motor voltage command. The inverter control device has, in generating PN voltage correction coefficient, a first mode in which the PN voltage correction coefficient is set to 1 when the DC voltage value is more than the reference DC voltage, and a second mode in which the value obtained by dividing the reference DC voltage by the detected DC voltage is set to the PN voltage correction coefficient.

Abstract: A reactor having a predetermined small capacity is connected to a rectifier, and a capacitor having a predetermined small capacity is connected between DC bus lines of the inverter. A PN voltage corrector calculates a ratio of the DC voltage detection value of the inverter obtained by the PN voltage detector to a predetermined DC voltage reference value of the inverter to thereby generate a PN voltage correction factor. A beat amount corrector calculates a fluctuation amount of the motor current from the motor current detection value obtained by the motor current detector and generates a reverse phase component of the motor current fluctuation amount. Thus, a small, light and low-cost inverter controller can be implemented.

Abstract: An inverter controller for driving a motor includes a rectifier having a reactor, an inverter, a capacitor, a generator which generates a voltage command value for each phase of the motor, a detector which detects a DC voltage between the DC buses of the inverter, a first corrector which calculates a voltage correction coefficient by comparing the DC voltage with a predetermined DC reference voltage, a second corrector which corrects the voltage command value by multiplying the voltage command value and the voltage correction coefficient, a selector which selects either two-phase modulation or three-phase modulation as a modulation type, a computer that computes a carrier frequency, and a pulse width modulation controller which controls a pulse width modulation so that a value of a voltage to be applied to the motor equals to the corrected voltage command value, by using the selected modulation type and the selected carrier frequency.

Abstract: An inverter control unit for motor driving includes a rectifier circuit for converting into a DC power a first AC power inputted from an AC power supply, which includes a diode bridge and a reactor connected to an AC input side or a DC output side of the diode bridge and having a small inductance, and an inverter for converting the DC power from the rectifier circuit into a second AC power so as to output the second AC power to a motor. Furthermore, a capacitor for absorbing regenerative energy of the motor, which has a small capacitance and an overvoltage protecting circuit whose impedance is lowered by overvoltage are connected between DC buses of the inverter.

Abstract: A reactor (5) having a predetermined small capacity is connected to a rectifier (2), and a capacitor (6) having a predetermined small capacity which is connected between DC bus lines of the inverter (3). A PN voltage corrector (10) calculates a ratio of the DC voltage detection value of the inverter obtained by the PN voltage detector (9) to a predetermined DC voltage reference value of the inverter (3) to thereby generate a PN voltage correction factor. A beat amount corrector (16) calculates a fluctuation amount of the motor current from the motor current detection value obtained by the motor current detector (15) and generates a reverse phase component of the motor current fluctuation amount. Thus, a small, light and low-cost inverter controller can be implemented.

Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device generates PN voltage correction coefficient by dividing the reference DC voltage by the detected DC voltage, and corrects the voltage command of each phase by multiplying the voltage command of each phase obtained by the motor voltage command generator with the PN voltage correction coefficient output from the PN voltage corrector, thus resulting in the corrected motor voltage command. The inverter control device has, in generating PN voltage correction coefficient, a first mode in which the PN voltage correction coefficient is set to 1 when the DC voltage value is more than the reference DC voltage, and a second mode in which the value obtained by dividing the reference DC voltage by the detected DC voltage is set to the PN voltage correction coefficient.

Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device includes a first motor voltage command corrector that corrects a voltage command of each phase by multiplying the each phase voltage command by a PN voltage correction coefficient, and a second motor voltage command corrector that corrects again the each phase voltage command once corrected by the first motor voltage command corrector, only when any one of the phase voltage commands corrected by the first motor voltage command corrector is larger than the inverter DC voltage, by multiplying the voltage command of each phase corrected by the first motor voltage command corrector by the inverter DC voltage value, and dividing the product of the multiplication by the maximum value of the phase voltage commands corrected by the first motor voltage command corrector.

Abstract: A reactor (11) having a predetermined small capacity is connected to a rectifier (2), and a capacitor (12) having a predetermined small capacity is connected between DC bus lines of the inverter (3), so that a small, light and low-cost inverter controller for driving a motor can be implemented, and even when an inverter DC voltage largely fluctuates and it is difficult to drive the motor, the motor can be kept driving by operating the inverter such that a voltage applied to the motor may stay constant by a motor voltage command corrector (17) which generates a motor voltage command correction value of the motor.

Abstract: An inverter controller for driving a motor includes a rectifier having a reactor, an inverter, a capacitor, a generator which generates a voltage command value for each phase of the motor, a detector which detects a DC voltage between the DC buses of the inverter, a first corrector which calculates a voltage correction coefficient by comparing the DC voltage with a predetermined DC reference voltage, a second corrector which corrects the voltage command value by multiplying the voltage command value and the voltage correction coefficient, a selector which selects either two-phase modulation or three-phase modulation as a modulation type, a computer that computes a carrier frequency, and a pulse width modulation controller which controls a pulse width modulation so that a value of a voltage to be applied to the motor equals to the corrected voltage command value, by using the selected modulation type and the selected carrier frequency.

Abstract: In a motor control apparatus of the present invention, a control section which receives an input voltage to an inverter circuit, a motor current flowing to a brushless motor and a motor current command value indicating the value of a current required to flow to the inverter circuit, and controls the inverter circuit by maintaining a phase of the voltage applied to the brushless motor when the value of the input voltage to the inverter circuit is smaller than the value of a voltage required to be applied to the brushless motor.

Abstract: The present invention discloses a power apparatus with the output voltage thereof made variable, which allows harmonics to be suppressed while an enhanced power factor being maintained. The power apparatus comprises an alternating current power source, a bridge rectifier circuit to subject alternating currents from the alternating current power source to full-wave rectification, a reactor connected between the alternating current power source and the alternating current input end of the bridge rectifier circuit and a capacitor connected via a bi-directional switch between the alternating current input end and the direct current end of the bridge rectifier circuit, further comprising a smoothing capacitor, a zero-crossing detecting means, a bi-directional switch drive signal generating means and a bi-directional switch driving means.

Abstract: The present invention discloses a power apparatus with the output voltage thereof made variable, which allows harmonics to be suppressed while an enhanced power factor being maintained. The power apparatus comprises an alternating current power source, a bridge rectifier circuit to subject alternating currents from the alternating current power source to full-wave rectification, a reactor connected between the alternating current power source and the alternating current input end of the bridge rectifier circuit and a capacitor connected via a bi-directional switch between the alternating current input end and the direct current end of the bridge rectifier circuit, further comprising a smoothing capacitor, a zero-crossing detecting means, a bi-directional switch drive signal generating means and a bi-directional switch driving means.

Abstract: An erythromycin A derivative represented by Formula wherein R1 is a group represented by the formula: a group represented by the formula: (c) pyridylacetyl, (d) cycloalkylmethyl or (e) 1,2 bis-(ethoxycarbonyl)vinyl, R2 is the same group as defined for R1, hydrogen, alkyl, alkanoyl, alkoxycarbonyl, R1 and R2 together may form ═CH—R14, or R1 and R2 together with the nitrogen atom to which they are attached may form: R3 is hydrogen, alkyl or cinnamyl, R4 is hydrogen, acetyl, ethylsuccinyl or nicotinoyl, A is —OC(═O)—R17, —OC(═O)—CH2—R17, —OC(═O)—NH—R17, —O—R17 or —OC(═O)—O—R17, and R5 and R6 are each hydrogen or alkyl.

Abstract: An erythromycin A derivative represented by the formula: wherein n is an integer of from 1 to 8, R1 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R2 is a pyridylmethyl group, a quinolylmethyl group, a pyridylsulfonyl group or quinolylsulfonyl group, R3 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or a cinnamyl group, R4 is a cladinosyloxy group or a group represented by the formula: wherein m is 0 or 1, R5 is a pyridyl group, a quinolyl group, a phenyl group, a phenyl group substituted with one, two or three members selected from alkyl groups having 1 to 6 carbon atoms, a nitro group, alkoxy groups having 1 to 3 carbon atoms and halogen atoms, or a pyridyl or quinolyl group substituted with one or two members selected from alkyl groups having 1 to 6 carbon atoms, a nitro group, alkoxy groups having 1 to 3 carbon atoms and halogen atoms; or a pharmaceutically acceptable salt thereof.

Abstract: An erythromycin A derivative represented by Formula (I): ##STR1## (wherein n is an integer of 2 to 4, R.sup.1 is a pyridylmethyl group, a furylmethyl group, a thienylmethyl group, a quinolylmethyl group or a benzyl group having 1 to 3 substitutents selected from the group consisting of an alkyl group having 1 to 5 carbon atoms, a nitro group, an alkoxy group having 1 to 5 carbon atoms, an amino group and an amino group substituted by 1 or 2 alkyl groups having 1 to 5 carbon atoms, R.sup.2 is the same group as defined for R.sup.1, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an acetyl group or a pyridylacetyl group, and R.sup.3 is an alkyl group having 1 to 5 carbon atoms or a cinnamyl group) or a pharmaceutically acceptable salt thereof has a strong antibacterial activity against not only known erythromycin-sensitive bacteria but also erythromycin-resistant bacteria and Haemophilus influenzae.