Seirel Automatismes - Electrical control panels for cableways and ski lifts

Seirel Automatismes is a French company specializing in electrical control panels for cableways and ski lifts.
Gefran’s ADV200 inverter with integrated STO (Safe Torque Off) board and AFE200 regenerative unit fully meet these demands and offer the system integrator an excellent price/performance ratio.

The customer

Seirel Automatismes is a company of Gérard Perrier Industrie Group. It is based in Lyon, France, where it was founded in 1985.

In 30 years it has become a specialist in cable transport and lifting, offering its final customers a variety of products and services that make it a reliable partner in mountain tourism.

It has thorough knowledge of safety rules and their application in this sector, and also provides after-sales management and maintenance of its systems.

Thanks to this know-how, it offers customers excellent service. Seirel Automatismes has also a laboratory specializing in the manufacture of cabinets AFE 30kW to several MW.

The process

Cable transport systems are specific examples of industrial lifting, called continuous motion: a closed-loop cable between two end terminals flows non-stop and carries a variable number of cars that can be stably fixed to the cable.

Machinery to drive the transport cable and the emergency cable by means of a winch and electric motor, control equipment and anchors for weight-bearing cables are usually installed at the upper station.

The lower station, also called “return station” or “tension station,” has mechanisms which keep all of the cables taut by means of adequate counterweights.

This application has a ”motor” phase and a “generator” phase. If there is no one to transport, the system is balanced and energy to overcome mechanical friction is the only energy required.

There are two different situations when passengers are transported. When the majority of passengers goes up, the electric motor works as a motor and draws energy from the grid. On the other hand, when the majority goes down, the electric motor works as a generator and brakes the

The problem

In the past, all cable systems were run by DC motors that provided high-power performance at relatively low cost.
They used a thyristor converter drive that generated high-energy harmonics on the grid. These had significant impact on the (normally weak) electrical grids in mountain towns where these systems operated.

In addition, the use of 4-quadrant AC/DC converters to manage the “generator” phase as well exposed the system to brief interruptions which, if occurring during generation, could trip the fuses due to overcurrent caused by failed switching of the thyristors.

This caused the entire system to stop, requiring intervention by the maintenance team and creating obvious problems for customers.

The solution

Gefran was one of the first companies to believe in IGBT regenerative units called Active Front End, which reduce grid harmonics to less than 3% of nominal power and make the motor torque/drive power factor equal to 1. In addition IGBT regeneration eliminates the problem of blown fuses due to switching failure.

Taking advantage of this state-of-the-art technology and competitive price, Seirel Automatismes changed from DC to AC motors driven with speed and current control by Gefran ADV200 vector inverters. In turn, the inverters are powered by AFE200 Active Front End units.

In this way, Seirel Automatismes became a pioneer in AFE regenerative applications and immediately gained a technological advantage over its direct competitors.

The modularity of Gefran’s inverters and regenerative units (compact modules up to 355 kW, then parallelable up to a maximum of 5) lets Seirel Automatismes create a compact but expandable solution up to a maximum of 1800 kW, enough to satisfy any request by its final customers.

Seirel Automatismes used the same ADV200 inverter to drive auxiliary movements such as automatic hooking of chairs in the station, chair parking, and synchronized movement of the skier walkway with ski lift speed.
In this way, the customer has a single stock of spare parts for all of the inverters and, therefore, a single operator interface.

Lastly, the STO (Safe Torque Off) board (standard on the ADV200 inverter and SIL3 certified) lets Seirel Automatismes operate the system in the best possible way, eliminating the use of expensive output contactors between inverter and motor in case of emergency, stopping, or maintenance of the motor.

All ADV200 and AFE200 electronic boards have three layers of coating to guarantee high resistance and excellent performance even in the presence of aggressive agents such as humidity, corrosion, and sea fog.

Therefore, these products are perfect in environments with wide temperature excursion, such as lower and upper stations of mountain cableways.  

Other info on the ADV200

ADV200 field-oriented vector inverters are the state of the art in precision control of asynchronous and brushless motors. They can be used in any system-based application demanding high dynamics and torque control in a power range from 0.75 kW to 1800 kW and voltages of 400-480 V and 690V.

It is especially suitable for industrial hoisting and for heavy industry markets such as metal (lamination lines, plate shearing, wiredrawing), industrial water and smoke treatment, and for the plastics industry in general (extrusion, blowing, injection molding).