Abstract: A DC bus control system for controlling power fluctuations in a DC bus connecting an input power source and a load, comprising: a main stabilization device including a first charging/discharging element and a first power converter; a plurality of the sub stabilization devices including a second charging/discharging element, a charging element, or a discharging element and a second power converter, wherein the plurality of the sub stabilization devices includes a first sub stabilization device having a charging/discharging element and a second power converter and at least one second sub stabilization device having a charging element or a discharging element and a second power converter, and a response speed of the first sub stabilization device is set such that a charging amount of the charging element or a discharging amount of the discharging element of the second sub stabilization device changes with a predetermined time constant.

Abstract: A direct current bus control system including a direct current bus connecting between an input power supply and a load, including a main stabilizing device including a first charge-&-discharge element and a first power converter, and at least one sub-stabilizing device including a second charge-&-discharge element, a charge element, or a discharge element, and including a second power converter, wherein the first power converter is configured to derive a bus voltage target value according to a power storage amount index of the first charge-&-discharge element, and to bidirectionally pass direct current power, so that the voltage of the direct current bus matches the bus voltage target value, and the second power converter is configured to derive a current target value, and to pass direct current power, so that a current equal to the current target value flows.

Abstract: A direct current bus control system including a direct current bus connecting between an input power supply and a load, including a main stabilizing device including a first charge-&-discharge element and a first power converter, and at least one sub-stabilizing device including a second charge-&-discharge element, a charge element, or a discharge element, and including a second power converter, wherein the first power converter is configured to derive a bus voltage target value according to a power storage amount index of the first charge-&-discharge element, and to bidirectionally pass direct current power, so that the voltage of the direct current bus matches the bus voltage target value, and the second power converter is configured to derive a current target value, and to pass direct current power, so that a current equal to the current target value flows.

Abstract: An optical device has a reflecting mirror using a particle-dispersed silicon material including silicon carbide and silicon. The reflecting mirror includes a plurality of segments joined to each other by reaction sintering. Producing the segments is easy in comparison with that of a reflecting mirror of one piece. Accordingly, it is possible to reduce probability of breakage of the segments and to shorten process time of production of a reflecting mirror.

Abstract: An optical device has a reflecting mirror using a particle-dispersed silicon material including silicon carbide and silicon. The reflecting mirror includes a plurality of segments joined to each other by reaction sintering. Producing the segments is easy in comparison with that of a reflecting mirror of one piece. Accordingly, it is possible to reduce probability of breakage of the segments and to shorten process time of production of a reflecting mirror.

Abstract: The present invention adopts a particle dispersed silicon material, comprising silicon carbide as dispersion particles, as a mirror substrate, subjects the mirror substrate to mirror finish polishing to form a mirror body, forms a reflecting film on the mirror body to form a mirror, and uses the mirror to form a large aperture optical system.

Abstract: The present invention adopts a particle dispersed silicon material, comprising silicon carbide as dispersion particles, as a mirror substrate, subjects the mirror substrate to mirror finish polishing to form a mirror body, forms a reflecting film on the mirror body to form a mirror, and uses the mirror to form a large aperture optical system.

Abstract: A laser beam from a laser beam oscillator is guided to an incidence light path of a beam splitter of a Michelson interferometer by means of a first guide mirror, reflected by a fixed mirror and a scanning mirror of the Michelson interferometer, and returned to the beam splitter, thus obtaining an interference light beam. The interference laser beam is guided to first and second laser beam detectors by means of a second guide mirror to detect variations in intensity of the interference laser beam. On the basis of the variations in intensity of the interference laser beam, an angle of inclination (.theta.) of the scanning mirror is measured.

Abstract: Sunlight passes through the light-transmission sections of a periodic pattern reticle of a sun sensor, and light components thus divided at regular intervals are incident on the light-receiving surface of a photoelectric converting section. The photoelectric converting section transfers charges stored in the light-receiving sections, in response to a pulse signal from a transfer pulse-generating section, to convert the light intensity distribution to a time series signal. A reference phase signal-generating section generates a reference phase signal whose polarity is inverted at an interval corresponding to the width and interval of the light-transmission sections, based on the pulse signal from the transfer pulse generator. An error voltage-detecting section multiplies the reference phase signal by the time series signal, and integrates the result of multiplication to detect an error voltage corresponding to the phase difference between the two signals.

Abstract: A star sensor mounted in a satellite subjected to a spinning motion includes an optical system for obtaining an image of a fixed star, a CCD area sensor as an image pickup device arranged at a focal point of the optical system, a signal processing circuit for receiving an output from the CCD area sensor through a preamplifier, and a CCD driving circuit connected to the CCD area sensor. The CCD area sensor is an interline type CCD. The optical axis of the optical system is perpendicular to a spinning axis of the satellite. The horizontal scanning direction of the CCD area sensor coincides with the direction of the spinning axis. For this reason, the star image is moved on the light-receiving surface of the CCD area sensor along the vertical scanning direction with the spinning motion of the satellite. The CCD driving circuit causes the CCD area sensor to perform time-delay integration at a speed corresponding to the spinning speed of the satellite.

Abstract: A star scanner according to this invention has an optical system for forming a star image, a photoelectric transducer arranged at a scanning section for the star image to be formed by the optical system, and a signal processor for generating detection data on the star image in accordance with a signal output from the photoelectric transducer. The optical detector fo the photoelectric transducer has semiconductor photosensitive elements arranged at the scanning section for the star image to be formed, and reticles, arranged between the semiconductor photosensitive elements and the optical system, to constitute a plurality of photosensitive sections and light-blocking sections on the photosensitive surface ofthe semiconductor photosensitive elements along a star image-scanning direction. The signal processor has means for generating detection data on the star image in accordance with the signal output of the semiconductor photosensitive elements.