Patent
Method and apparatus for controlling refrigerator cycle
TLDR
In this paper, the duty factor of the PWM pulse signal is reduced so as to be cut off after the overcurrent has been detected, without stopping the operation of the compressor and the compressor motor.Abstract:
In case an instantaneous over-current flowing through switching elements is detected between a predetermined rise time point and a predetermined fall time point of each of the PWM control pulses, the output of the duty control circuit is stopped immediately. In other words, the duty factor of the PWM pulse signal to be outputted as it is under the normal conditions is reduced so as to be cut off after the over-current has been detected. Therefore, it is possible to protect the switching elements of the inverter from breakdown due to over-current, without stopping the operation of the compressor and the compressor motor.read more
Citations
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Patent
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References
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Patent
Apparatus and method for controlling the operating frequency of compressor in air conditioning apparatus
TL;DR: In this article, the line voltage of any two phases of a three phase AC power supply is detected through a high pass filter and an amplifier is used to amplify the voltage by a microprocessor.
Patent
Current controlled inverter
TL;DR: In this paper, the instantaneous inverter phase currents are monitored by sensors 16, 17, 18 and used as feedback to enable the inverter phases to be switched so that each phase current conforms in frequency and amplitude to a phase reference sinusoid produced by a sine wave generator.
Patent
Picture scanning reader
TL;DR: In this article, the authors proposed to improve the processing speed of a picture scanning reader by normalizing a picture signal under the condition of an analog signal and then performing digital conversion, which is the case where normalization is made under the conditions of digital signals and obtain a reproduced picture having no light and shade unevenness.
Patent
AC-to-DC power converter with improved power factor and overvoltage suppression
TL;DR: In this paper, an AC-to-DC power conversion by connecting GTO elements to the positive arms of a three-phase full wave bridge circuit is described. And the GTO element is connected to a load from an AC power supply, and the mode of making the current flowing to the load flow back at the time of interruption of the power supply mode is switched over.
Patent
Multiphase pulse width modulator for a multiphase motor
TL;DR: In this paper, a multiphase pulse width modulator for an N-phase motor is presented, which allows continuous conduction of current through each winding in the motor at all times of the motor's operation.