Patents Assigned to Tokyo Denryoku Kabushiki Kaisha
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Patent number: 4329637Abstract: A shaft torsional oscillation signal of a rotatable torsional system including a rotor of a synchronous machine, at least one rotatable body and a shaft coupling the synchronous machine and the rotatable body, is detected. The shaft torsional oscillation signal with a specific frequency is made to advance the phase thereof by a stabilizing control device. The field voltage of the synchronous machine is so controlled that a sub-synchronous resonance (SSR) of the rotatable torsional system caused by the specific frequency is restrictedly controlled by the shaft torsional signal of the specific frequency phase-advanced.Type: GrantFiled: April 8, 1980Date of Patent: May 11, 1982Assignees: Tokyo Denryoku Kabushiki Kaisha, Tokyo Shibaura Denki Kabushiki KaishaInventors: Tosio Kotake, Katuaki Watanabe, Kaoru Koyanagi
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Patent number: 4328556Abstract: In a system of controlling the operation of a plant by using a digital computer, operation control procedures are classified according to various states of the plant process variables. The control procedures comprise essential break points of the plant running, and process controlling operations, process supervision operations, information display operations and other processings related to the Tables corresponding to the operation control procedures are prepared containing classified items which are described according to a predetermined format. The contents of the tables are converted into machine words and stored in the memory device of the computer. The computer is provided with means responsive to a changed process signal from the plant for selecting a table corresponding to the changed process signal (representing a changed state) to form an operating signal which is used to control the plant. There is also provided means for displaying and modifying the content of a selected table.Type: GrantFiled: April 16, 1979Date of Patent: May 4, 1982Assignees: Tokyo Denryoku Kabushiki Kaisha, Tokyo Shibaura Denki Kabushiki KaishaInventors: Masao Abe, Haruo Kawahara, Yoichiro Kogure, Masahiro Maeohmichi, Tetsuo Takeuchi, Norihiko Karashima
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Patent number: 4313169Abstract: At an end (11) of a power transmission line (10), a fault detecting system monitors variations resulting from a fault in voltage and current being transmitted through the line and calculates the distance between the end and location (20) of the fault by the use of the variations and a line constant inherent to the line, such as that given by the characteristic impedance and the propagation constant, to thereby locate the fault with a sufficient accuracy by directly using the commercial frequency and without affected by the impedance that accompanies the fault. The system can calculate the fault impedance from the distance and those backward impedances seen at the end and an opposing end (12) of the line backwardly of the location of fault.Type: GrantFiled: August 3, 1979Date of Patent: January 26, 1982Assignee: Tokyo Denryoku Kabushiki KaishaInventors: Toshio Takagi, Yukinari Yamakoshi
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Patent number: 4231258Abstract: In a method for detecting foreign matters present in gas sealed electrical apparatus including a tank at the ground potential and containing an insulating gas and a high voltage live part disposed in the tank, a voltage is applied to the high voltage live part causing generation of ultrasonic waves and the ultrasonic waves propagated through the tank is sensed by a sensing element mounted on the tank.Type: GrantFiled: January 2, 1979Date of Patent: November 4, 1980Assignees: Tokyo Shibaura Denki Kabushiki Kaisha, Tokyo Denryoku Kabushiki KaishaInventors: Shinichi Menju, Kunio Takahashi, Eiichi Haginomori, Yoichi Murakami, Eiichi Zaima
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Patent number: 4075697Abstract: Apparatus for monitoring two sinusoidal electric quantities of a common period, comprises two similarly timed samplers, an arithmetic unit for combining, in accordance with a preselected relation, three consecutive samples of each electric quantity so as to produce an output signal which is independent of time and phase relations between the sampling pulses and the respective quantities. The output signal may be determined solely by peak values of the respective quantities, phase difference between the electric quantities, and timing period. The apparatus further comprises a discriminator circuit having a reference level and responsive to the output signal for producing a signal for use in monitoring the electric quantities.Type: GrantFiled: October 21, 1976Date of Patent: February 21, 1978Assignees: Tokyo Denryoku Kabushiki Kaisha, Kabushiki Kaisha MeidenshaInventors: Tomoyoshi Ochiai, Takeshi Hayashi, Mituhiro Furuse
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Patent number: 4073008Abstract: The amplitude value of a sinusoidal wave is calculated by operating means which processes absolute values of two data samples which are sampled from the sinusoidal wave at two points spaced 90.degree. electrical degrees apart thereby producing an electrical signal proportional to the amplitude value. The operation means comprises a comparator, a combination of an adder and a subtractor, or a combination of a comparator and an adder. The output of the comparator or the combination is multiplied with a predetermined coefficient and then added together to produce said signal.Type: GrantFiled: August 26, 1976Date of Patent: February 7, 1978Assignees: Tokyo Shibaura Denki Kabushiki Kaisha, Tokyo Denryoku Kabushiki KaishaInventors: Fumio Andow, Tetsuo Matsushima, Minoru Iwasaki
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Patent number: 4073009Abstract: The apparatus comprises a sampling hold circuit for sampling the amplitude of a sinusoidal wave at a predetermined frequency, a data sample extracting circuit for extracting two data samples at two points immediately before and after the peak value of the sinusoidal wave, and an operation circuit responsive to the absolute values of the two data samples for calculating the amplitude value of the sinusoidal wave.Type: GrantFiled: August 26, 1976Date of Patent: February 7, 1978Assignees: Tokyo Shibaura Denki Kabushiki Kaisha, Tokyo Denryoku Kabushiki KaishaInventors: Fumio Andow, Tetsuo Matsushima, Minoru Iwasaki
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Patent number: 4006348Abstract: Apparatus for monitoring two sinusoidal electric quantities of a common period, comprises two similarly timed samplers, an arithmetic unit for combining, in accordance with a preselected relation, three consecutive samples of each electric quantity so as to produce an output signal which is independent of time and phase relations between the sampling pulses and the respective quantities. The output signal may be determined solely by peak values of the respective quantities, phase difference between the electric quantities, and timing period. The apparatus further comprises a discriminator circuit having a reference level and responsive to the output signal for producing a signal for use in monitoring the electric quantities.Type: GrantFiled: September 23, 1974Date of Patent: February 1, 1977Assignees: Tokyo Denryoku Kabushiki Kaisha, Kabushiki Kaisha MeidenshaInventors: Tomoyoshi Ochiai, Takeshi Hayashi, Mituhiro Furuse
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Patent number: 3972470Abstract: A supervisory control system for an electric power system comprises a synchronized encoder for producing digital signals from voltage and/or current data detected by at least one of a number of detecting devices for such data coupled to the power system at various points. Inherently stationary data detected by similar detecting devices are converted into digital signals by asynchronous encoders. Responsive to such digital signals, data processing means produces address signals representative of the addresses of the detecting devices and processes the digital signals in compliance with programs for various supervisory control and with reference to the address signals to produce control signals, which are sent to circuit breakers, voltage regulators, and the like to protect the power system against troubles.Type: GrantFiled: March 27, 1975Date of Patent: August 3, 1976Assignee: Tokyo Denryoku Kabushiki KaishaInventor: Toshio Takagi
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Arrangement for supplying input signals to central processing units without interruption of programs
Patent number: 3949374Abstract: A read-out signal generator supplies read-out signals through a read-out bus bar to sources of first data signals and buffer memories storing second data signals produced by accompanying central processing units (CPU's) to make the read-out bus bar transmit also the first and second data signals in timed relation to the read-out signals. A coupling device supplies read-in signals with reference to the read-out signals and transfers the first and second data signals from the read-out bus bar to a read-in bus bar, which supplies the transferred data signals to the CPU's in predetermined time relation to the read-in signals. The coupling device may either be a mere connection (in which case the read-out signals serve as the read-in signals) or a data bank.Type: GrantFiled: June 24, 1974Date of Patent: April 6, 1976Assignees: Tokyo Denryoku Kabushiki Kaisha, Kabushiki Kaisha MeidenshaInventors: Toshio Takagi, Shiro Seki, Akihiro Ito