IEEE Electrification Magazine - September 2014 - 21

The vehicle's HV circuit upgrade consisted of adding a
connection to the underbody magnetic shoe by means of
an HV contactor (located on the roof of the trams, as
shown in Figure 4) to allow connection and disconnection
of this circuit.
In addition, some changes were introduced to the LV circuit (24-V dc) of the trams to include the elements required
to operate the Tramwave system, including several circuit
breakers and relays. The motion of the magnetic shoe is
driven by two hydraulic pistons controlled by a control unit
positioned under the driver cab (see Figure 5).
As the SIRIO tram is bidirectional, the controls for the
new system were duplicated in both driving cabs and
included (see Figure 6): a switch allowing the driver to
choose between the overhead or the ground power supply,
buttons to open or close the main switch, and light indicators to show the state of each button and switch.
When the vehicle reaches the trial ground-fed section,
the following sequence of operations is carried out:
1) opening the main circuit breaker, 2) lowering the pantograph
on the roof, 3) closing the contactor of the ground power
supply, 4) lowering the underbody magnetic shoe, and
5) closing the main circuit breaker.
The logic of the vehicle also included inhibiting the lowering of the
ground-level collector when the pantograph of the roof was raised. Similarly, the pantograph of the roof could
be raised only if the ground-level collector was also raised. In the axis of
the ground-level pantograph gearboxes, two angular-position sensors were
fitted that were used to indicate the
status of the collector ("up" or "down")
on the driving desk, interfacing also
with the TCMS.
To provide visual information to
the driver of the state of the groundlevel pantograph, a color camera was mounted in a lateral
position on the bogie so as to resume the lowering and raising processes, providing a TV signal to one display in each
driving cab.

Figure 7. An HV contactor for connecting and disconnecting the
Tramwave contact line.

protection degree of IP55 was mounted on the roof of
carbody R.
The ground-level current collections system, including
both the collector and the pantograph, was mounted on the
trailed bogie of the vehicle carbody.
This system has limited size and
dimensions to allow for the mounting
in the area between the girders and
tubular beams of the bogie frame;
therefore, all movements (raising and
lowering) of the system without interference with neighboring parts of the
bogie and the underbody are guaranteed. To allow this, the ground-level
pantograph is fixed to the bogie frame
by means of a plate screwed in
correspondence of the two tubular
beams screwed by four anchoring systems in the center line of the carriage
(see Figure 7). In addition, the electrohydraulic brake system was shifted
from the center line of the bogie to the left.
The solution chosen for mounting the current collection system was adapted (see Figure 1). Under condition of
maximum vertical movements (wheel wear and subsidence of the suspensions), the minimum distance (shape of
the lower parts) from the plane of the iron was 60 mm
(see Figure 2).

The electrical
contact is ensured
by the attractive
force of the
permanent magnets
mounted inside the
magnetic shoe.

Mechanical Modifications
Some noninvasive mechanical changes were performed to
allocate space for mounting the new system with a power
supply from the ground on the vehicle, involving the carbody and the bogies.
The hydraulic system was installed at the underbody
of the cab and connected at the carbody, which, in turn,
interfaced with the trailed bogie. A metal box with a

biography
Luigi Pastena (Pastena.Luigi@ansaldobreda.it) is a senior
researcher at Ansaldobreda. He collaborated on the
TramWave Project with the Ansaldo STS team from 2008
to 2011.

IEEE Elec trific ation Magazine / S ep Tem be r 2 0 1 4

Table of Contents for the Digital Edition of IEEE Electrification Magazine - September 2014