| KYOSAN ELECTRIC MFG. CO., LTD. Patent applications |
| Patent application number | Title | Published |
|---|
| 20110134669 | UNBALANCED VOLTAGE COMPENSATION METHOD, UNBALANCED VOLTAGE COMPENSATOR, THREE-PHASE CONVERTER CONTROL METHOD, AND CONTROLLER OF THREE-PHASE CONVERTER - In compensating for unbalanced voltages of three-phase AC, instantaneous values of wye-phase voltages 120° out of phase with each other are obtained from line voltages using a centroid vector operation, symmetrical component voltages of three-phase balanced system are obtained from the instantaneous values of wye-phase voltages, a compensation signal to compensate unbalanced voltages of three-phase AC is generated from zero-phase-sequence voltage of symmetrical component voltages is generated, wye-phase voltages 120° out of phase, the unbalanced voltages of which are compensated, are obtained from the compensation signal and the symmetrical component voltages, a control signal of a PWM conversion is generated based on the compensated wye-phase voltage compensated, and the unbalanced voltages of three-phase AC are compensated. The amount of time to compensate the three-phase unbalanced voltages required for detecting an unbalance of voltages and generating a control signal can be shortened. | 06-09-2011 |
| 20110032047 | PULSE MODULATED RF POWER CONTROL METHOD AND PULSE MODULATED RF POWER SUPPLY DEVICE - The pulse modulated RF power control method includes an output amplitude control step for controlling amplitude of a pulse output, and a duty control step for controlling a duty ratio of the pulse output. The output amplitude control step performs a constant amplitude control to control an amplitude value of the pulse output so that the amplitude value becomes equal to a set amplitude value. The constant amplitude control according to the output amplitude control, for instance, gives a feedback of the amplitude value of the pulse output outputted by the power control, obtains a difference value between the feedback value and the set amplitude value, and controls the amplitude value of the pulse output so that the difference value becomes zero. | 02-10-2011 |
| 20100187998 | ABNORMAL DISCHARGE SUPPRESSING DEVICE FOR VACUUM APPARATUS - The present invention is directed to an apparatus for suppressing abnormal electrical discharge used for vacuum equipment which supplies power from a high-frequency power source to a plasma reaction chamber and executes a film formation process, provided with a power controller for controlling the high-frequency power source based on a deviation between a power command value and a power feedback value, and a cutoff controller for cutting off the power supply from the high-frequency power source to the plasma reaction chamber, based on a detection of the abnormal electrical discharge within the plasma reaction chamber. The cutoff controller exercises a first handling cutoff control and a second handling cutoff control, each having a different cutoff time. The first handling cutoff allows ions to remain in the plasma reaction chamber, and exercises the cutoff control over the high-frequency power source within a time duration which allows an arcing element to disappear. On the other hand, the second handling cutoff control exercises cutoff control over the high-frequency power source within a time range which allows abnormal arc ions to disappear. Accordingly, it is possible to supply power to plasma stably. | 07-29-2010 |
