The Administration decided to invest 430 trillion yens in public facilities during coming ten years in June 1990 aiming to promote the national policy toward the better quality of life for its people in the 21st century. Social systems that forms the basis are expected to play an important part in achieving this target.
This paper gives views on the situation, environment, fields, technologies, and trends of social systems.

Card gate systems for leisure facilities have attracted attention. Prepaid cards for the gate system retain information on tickets and facilities necessary for management as well as information on money. The system is advantageous to the management for rationalizing facility management at the gates and to the users for its cashless convenience. This paper introduces the configuration and components of Fuji Electrics system with examples.

Recent garbage incineration plants have been equipped with a power generating unit and become large-sized and sophisticated. This paper describes the result of supply and the control system of incineration plants with a generating facility. It also introduces a network and an optimum operation system for two or more incineration plants and a pneumatic garbage transfer system to rationalize garbage collection and transfer as new environmental business.

The extension of expressways is planned to be further accelerated and various facilities will be increased to secure safe and smooth traffic. These facilities demand high-grade functions and performances based on electronics.
This paper gives an outline of advanced systems for bridges and tunnels and Fuji Electric's attitude for new development in this field.

Because of the advancement of medical treatment and the mission of hospitals, hospital facilities and systems must work day and night. It becomes more and more important to secure the safety and reliability of electrical equipment.
This paper introduces (1) a supervision and control system made redundant with a minicomputer and automatic control thereof, (2) a stable power supply system, flame retardation technology and measures against high harmonics, and (3) a hot-line insulation resistance monitor system aiming at predictive maintenance.

To secure integrity and social activities in a basin including rivers, lakes, and dams and in a harbor and coastal area, it is essential to maintain the safety from floods and tidewater, which requires to improve monitoring efficiency and make efficient use of data.
This paper introduces the present and future of these systems taking a tidewater facility and a river pumping station as examples.

This paper introduces Fuji Electric's power supply system taking the one supplied to Shin-Tokyo International Airport as an example.
(1) 66-kV
ubstation for the central air conditioner,
(2) 6-kV standby generating system,
(3) Switching stations A to F.
The complete dual system is described in (1) and (3), and the parallel operation of a diesel generating system and a gas-turbine generating system, in (2).

In information society, public facilities needs to include an integrated-management system aiming at energy saving, labor saving, and wide-area management. The supervision and control system as the core demands easier usage, higher performance and reliability. Fuji Electric has developed a high-reliability system, SOINS series, which realizes free construction of a system corresponding to a facility scale, display and operation easy to use, data transmission and processing matching the required management level, expandability and quick restoration from a fault. This paper introduces the features and functions of the series.

Among analyses of a gas circuit breaker (GCB) using SF₆ with superior insulation and current interruption ability, the analysis of interrupting phenomena is one of the most important ones related to interrupting capacity. But the possible range of analysis was limited because an arc, high-temperature gas flow and breaker motion including their interactions have to be analyzed. Recent progress in computer and analysis technology has made this complicated analysis possible, contributing to GCB development. This paper describes interrupting operation analysis, fluid analysis, and measurement of withstand voltage characteristics.

Gas-insulated circuit breakers using sulfur hexafluoride (SF₆) have been making remarkable progress in size, reliability, and capacity. Testing technology to verify interrupting capacity has been improving as well.
This paper describes the importance of synthetic-test technology to make up for testing equipment and make tests match interrupting phenomena in actual systems and introduces single-phase synthetic tests, three-phase ones (for systems with noneffective neutral ground and with effective one) from among short-circuit tests, and a synthetic test for capacitive current interruption.

Pulsed power technology that generates high power in a short time and transmits, controls, and uses it in various forms has remarkably progressed recently Its essence is to compress and concentrate large power into an extremely small space and short time. For this purpose, it is necessary to form available energy (power × time) into pulsed large power. This paper mainly describes the experimental results on explosive generating systems as pulsed power supply and refers to an outline of a rotating storage compulsator and a pulsed-power forming equipment using ferromagnetic cores.