Expressway are equipped with various facilities which play an important role to maintain safe and smooth traffic. The extension of roads and increase in social complexity demand sophisticated functions for these facilities.
This paper gives an outline of Fuji Electric's achievements and its attitude toward future development in this field.

The management of highways has become a matter of great importance with increase in their length in service. The supervisory control system is the center of centralized and unified management, and efforts have been made to enhance reliability and man-machine functions.
This paper describes an outline of the system and its trends.

The electrostatic precipitator has attracted a great deal of attention as powerful equipment reducing the construction and maintenance cost of tunnel ventilation system.
This paper outlines the development, system configuration, and future technical problems of the precipitator for road tunnels.

The number of road tunnels has increased as construction shifted from running-through highways to crossing highways, and tunnel ventilation control has been regarded as more important.
This paper gives an outline of tunnel ventilation control and examples of Fuji Electric's supply and study with simulation.

The power system for roads is essential equipment supplying power to lighting, information board, ventilation, disaster prevention, communication, and other systems in interchanges, tunnels, etc. The power system consists of power receiving and distributing equipment, exclusive-use power plants, and uninterruptible power supplies.
This paper describes the planning, actual erection, and technical tendency of the system concentrating on receiving and distributing equipment.

Various instruments and systems are used in the field of roads for supporting safe and comfortable traffic, saving management cost , and preventive maintenance.
This paper describes an outline of the major equipment from among them and introduces Fuji Electric's products.

Almost all hydraulic research laboratories in Japan and overseas have automated data acquisition. However, there are few examples completing laboratory automation including automatic calibration of performance measuring instruments and automated operation from start to shop. Fuji Electric, in recent modernization of its old equipment, has renovated the performance measuring instruments to further improve measuring accuracy and also introduced laboratory automation to save labor, to speed up experiments, and to automate data processing. The paper outlines the points.

This paper describes the distribution of cavitation in a large low-head bulb turbine with a runner diameter exceeding the head, and in particular, a method of estimating its vertical distribution from model cavitation test results and three-dimensional flow analysis around the runner. Further, it gives a new conversion method for cavitation characteristics considering this vertical distribution. The method makes it possible to estimate the characteristics of a large low-head bulb turbine with high reliability from its model test result, which have hardly been investigated so far.

Recently increasing energy cost has put low-head hydroelectric power plants into an economically competitive position. The civil portion accounts for a large rate of construction cost in a development at a low-head site; therefore, it is very important to raise specific speed to minimize the size of turbine-generators. Fuji Electric has developed bulb turbines for low-head plants In particular, efforts has made to develop high specific speed ones in these few years. This paper gives an outline of the developments results.

Fuji Electric developed a new Kaplan turbine with high cavitation performance for Sasado power plant of Chubu Electric Power Co., Inc., where the existing Francis turbine was replaced with the 8-bladed Kaplan turbine. The existing building and draft tube had to be used as it was, resulting in positive suction head. Longer blades than usual as well as optimized pressure distribution on blade surfaces improved cavitation performance without increase in cost. The model test verified that the new runner could be operated with positive suction head.

Reducing maintenance in hydraulic power plants has seriously been demanded recently because of difficuties in maintenance due to their special site conditions and steep rise in labor costs.
From among Fuji Electric's technologies enhancing maintenance saving in hydraulic power plants, this paper introduces recent developments in practical use, such as bearings with hcat pipes for water turbines, air-cooled bearings for hydraulic turbine generators, and an improved method for fixing stator windings in core slots.

Fuji Electric put epoxy resin insulated coils into practical use first in Japan. This paper describes application of the result obtained by investigating the characteristics of epoxy resin insulation in the first machine operated for 30 years is utilized for life diagnosis. Further, it refers to the superiority of epoxy resin insulation to compound insulation proved by data, problems of insulation diagnosis now prevailing, and a method for life diagnosis newly developed and in use.

With the progress of programmable controllers, the control system for hydraulic power station has developed into a total digital control system including primary regulating functions, such as functions of an automatic voltage regulator for sysnchronous generators and functions of an electric controlling unit of electro-hydraulic governor for hydraulic turbines.