Abstract: An apparatus for detecting the amplitude and phase of an a.c. signal. The apparatus includes a signal detection circuit for detecting the a.c. signal, a signal splitting circuit for splitting the detected a.c. signal into first and second a.c. signals out of phase with each other by 90.degree.. The signal splitting circuit includes a first order lag circuit having a phase lag, a subtractor, and first and second amplifying circuits. The apparatus also includes a phase compensation circuit coupled to the signal splitting circuit for receiving the first and second a.c. signals from the signal splitting circuit and for advancing the phase of an output signal of the apparatus by the phase lag of the first order lag circuit. The phase compensation circuit also includes an amplitude and phase detection circuit for detecting the amplitude and phase of the detected a.c. signal by implementing a polar coordinate transformation of the first and second a.c. signals received from the signal splitting circuit.

Abstract: An apparatus for detecting the amplitude and phase of an a.c. signal detects the a.c. signal with signal detection means (4), calculates an a.c. signal that is phase-shifted by the amount of the phase characteristic .phi. of the calculation circuit (14) at the frequency of the detected a.c. signal, multiplies the detected a.c. signal by cos .phi., and multiplies by 1/sin .phi. the multiplication result subtracted by the phase-shifted a.c. signal.

Abstract: A power converter controlling apparatus outputs voltage signals different in phase from phases of commutation voltages of each switching device by 90 degrees to transform the voltage signals and the commutation voltages in conformity with polar coordinate transformation, and outputs amplitudes of the commutation voltages and the phase differences of the commutation voltages to a reference phase based on the results of the transformation to operate phase-control angles of each switching device on the amplitudes and the phase differences.

Abstract: An apparatus for detecting the amplitude and phase of an a.c. signal. The apparatus includes a signal detection circuit for detecting the a.c. signal, a signal splitting circuit for splitting the detected a.c. signal into first and second a.c. signals out of phase with each other by 90.degree.. The signal splitting circuit includes a low-pass filter, and a differentiation circuit. The apparatus also includes a phase compensation circuit coupled to the signal splitting circuit for receiving the first and second a.c. signals from the signal splitting circuit and for advancing the phase of an output signal of the apparatus by the phase lag of the low-pass filter. The phase compensation circuit also includes an amplitude and phased detection circuit for detecting the amplitude and phase of the detected a.c. signal by implementing a polar coordinate transformation of the first and second a.c. signals received from the signal splitting circuit.

Abstract: An apparatus for detecting the amplitude and phase of an a.c. signal detects the a.c. signal with signal detection means (4), calculates an a.c. signal that is phase-shifted by the amount of the phase characteristic .phi. of the calculation circuit (14) at the frequency of the detected a.c. signal, multiplies the detected a.c. signal by cos .phi., and multiplies by 1/sin .phi. the multiplication result subtracted by the phase-shifted a.c. signal.

Abstract: An apparatus for detecting the amplitude and phase of an a.c. signal detects the a.c. signal with signal detection means (4), calculates an a.c. signal that is phase-shifted by the amount of the phase characteristic .phi. of the calculation circuit (14) at the frequency of the detected a.c. signal, multiplies the detected a.c. signal by cos .phi., and multiplies by 1/sin .phi. the multiplication result subtracted by the phase-shifted a.c. signal.

Abstract: An artificial intelligence software shell for plant operation simulation includes a blackboard module including a database having objects representing plant elements and concepts. A rule-based knowledge source module and a case-based knowledge source module, in communication with the blackboard module, operate on specific predefined blackboard objects. An input data module, in communication with the blackboard module, enables a user to input data to the shell. A control module, in communication with the knowledge source modules and the input data module, receives all input data and controls operation of the knowledge source modules in accordance with a predetermined knowledge source interruptibility/priority scheme. The control module including an event detector module having a hash table defined by a chaining algorithm.

Abstract: An interactive graphic recognition and data processing system includes an image reader for reading a facility drawing in which facility symbols are drawn, a display device for displaying the facility drawing read by the image reader overlapped with a topographical drawing corresponding thereto, a mouse for designating the position of the facility symbol displayed on the display device, a recognition device for recognizing the facility symbol designated by the mouse by comparing the same with a plurality kinds of facility symbols previously stored and causing the facility symbols recognized thereby to be displayed in different color from the color of the facility symbols which have not yet been recognized, and a memory for storing therein positional data in the topographical drawing of the facility symbol recognized by the recognition device and attributive data about the facility symbol as data base.