As development of hybrid and electric vehicles progresses
in the automobile industry, in 2000, JR East started
development of a new power system using the New Energy
Train (NE Train) test car, putting the Series Kiha E200 diesel
hybrid railcar into commercial service in 2007. Subsequently,
we fitted the NE Train with high-capacity storage batteries in
2008 and started development of a catenary and batterypowered
hybrid railcar that can run on non-electrified
sections. This was followed by various tests until March
2012 when practical use was shown to be feasible, so
we produced Series EV-E301 pre-production cars and
introduced them on some sections of the Tohoku main line
and Karasuyama Line in March 2014.
This article overviews the Series EV-E301, particularly
development of the battery-powered hybrid railcar system.
Railways are said to have high energy efficiency compared
to other transport modes. However, much of the energy
railway operators use for operations goes to running trains.
For that reason, curbing energy consumption and reducing
CO2 emissions is an important issue. Measures taken to
make rolling stock more energy efficient have included
reducing weight, making drive systems more efficient, and
utilizing regenerative braking effectively.
Diesel railcars running on non-electrified sections
cannot, in principle, be equipped with regenerative braking
systems, so they are less efficient than EMUs. They also
have problems with exhaust gases and noise. Consequently,
we decided to develop the NE Train test car in an effort
to reduce the environmental load of rolling stock running
on non-electrified sections through innovations in drive
systems. The success of the NE Train was demonstrated in
July 2007 with the introduction of the Series Kiha E200 on
the Koumi Line for practical use as a diesel hybrid railcar.
This was followed by the Series HB-E300 introduced from
October to December 2010 as ‘resort hybrid railcars’ in the
Nagano, Akita, and Aomori areas.
Meanwhile, battery performance in areas such as output
and capacity has been increased tremendously in the
automobile industry with progress in development of hybrid and electric automobiles, and price has dropped. Against
this backdrop, JR East shifted its focus to the feasibility
of fitting trains with high-capacity batteries for running on
non-electrified sections using electrical energy stored in
batteries. We modified the NE Train into a catenary and
battery-powered hybrid railcar (dubbed ‘Smart Denchi Kun’)
in 2008 using knowledge gained from diesel hybrid railcar
development, and started development of a catenary and
battery-powered hybrid railcar system including wayside
charging facilities. This system supports operation on both
electrified and non-electrified sections, thereby increasing
rolling stock operational efficiency. Other effects include
reduced maintenance by reducing mechanical parts such
as engines and transmissions, reduced engine exhaust,
and reduced CO2 emissions and noise. Various tests were
performed subsequently until March 2012, showing practical
use to be feasible, so we produced Series EV-E301 preproduction
cars and introduced them on some sections
of the Tohoku main line (Utsunomiya to Hoshakuji) and
Karasuyama Line in March 2014.
|Trainset and Rolling Stock Performance
The Series EV-E301 has EV (Energy storage Vehicle) as its
rolling stock type, indicating that it is a catenary and batterypowered
hybrid railcar. It is a two-car fixed trainset with car
No. 1 at the Utsunomiya end being a Type EV-E300, and car
No. 2 at the Karasuyama end with two pantographs being a
Type EV-E301. Each car can carry 133 passengers.
In terms of per formance, the maximum speed
is 100 km/h; the acceleration is 2.0 km/h/s, and the
deceleration is 3.6 km/h/s.
|Hybrid System using Overhead Catenary
In electrified sections, the trainset raises its two pantographs
to run on power from the overhead catenary and charge
At the Hoshakuji Station junction between the
electrified and non-electrified sections, the pantographs
are lowered and the train runs on battery power in the non-electrified section.
Arriving at Karasuyama Station, the pantographs are
raised for quick charging at the new charging facility there.
In this way, the Series EV-E301 raises and lowers its
pantographs depending on the presence of overhead
catenary at the running section to allow direct service
between electrified and non-electrified sections. The
frequency of pantograph raising and lowering is greater than
with ordinary rolling stock. Furthermore, electrical current
restrictions differ at quick charging by charging facilities
depending on the catenary conditions, such as charging
at greater collection currents than with ordinary overhead
catenary. For this reason, the Series EV-E301 has equipment
for identifying the type of overhead catenary, which receives
location information from the wayside so the train itself
automatically recognizes the type of overhead catenary at
the running location.
Photo: Exterior view of EV-E301 Hybrid Railcar (JR East)
Photo: ACCUM Logomark (JR East)
Photo: Interior of EV-E301 passenger cabin (JR East)
Photo: Cab equipment of EV-E301 (JR East)
Photo: On board display showing energy flow (JR East)
The overall concept of the Series EV-E301 is to be ‘next-generation
rolling stock leading to a people-friendly future’,
expressing the innovation of the catenary and batterypowered
hybrid railcar system. The carriage design theme also reflects the image of the region along the Karasuyama
Line where it has been introduced.
• Expressing innovation
A simple impression is created through the new front
shape and striped livery expressing innovation.
• Expressing environmental friendliness
The silver/green livery expresses consideration for the
environment, harmony with the wayside scenery, and
• Expressing catenary and bat tery-powered hybrid
The under-floor battery boxes for the traction circuit
and the pantographs are coloured green to harmonize
the exterior. This promotes the Series EV-E301’s main
characteristic of being a catenary and battery-powered
hybrid railcar system.
We aimed to create an image of an innovative cabin not
seen before on commuter trains. This includes aspects
such as indirect LED lighting arranged continuously, new ceiling cross-sectional shape, and cabin interior featuring
a black upper area at end walls to clearly identify the
information display space to passengers.
• Next-generation service
Keeping in mind the concept of universal design used
for the Series E233, we aimed to make the cars easy for
anyone to use. This included enhancing wheelchair spaces.
• Potential of Karasuyama Line
Elements with a feel of greenery, colour, and vibrancy
were employed for the seat and floor design. These
elements include features of the wayside scenery
offering a feel of the seasons, traditional crafts typified by
Japanese paper, and the Yamaage festival enlivening the
The public was asked to submit suggestions for the
nickname of the Series EV-E301, and ‘ACCUM’ was chosen
(from accumulator or storage battery). The car’s exterior
bears the ACCUM logomark with an image of the flow of
energy between the overhead catenary, battery, and motor.
The straight body is 19,570-mm long, 2800-mm wide, and
3620-mm high. The total height with pantograph retracted is
3980 mm to run through smaller tunnels. The floor height is
The body is a lightweight stainless-steel construction except
in part of the underframe where strength is needed, and the
head structure is reinforced at the front as a countermeasure
to damage in level-crossing accidents. Reinforcement was
added as necessary to improve body strength because the
Series EV-E301 is heavier than conventional cars despite
use of lighter materials due to the onboard batteries. On
the other hand, the weight had to be reduced as far as
possible to keep battery consumption down. Consequently
we changed materials to aluminium, added holes to reduce
weight, and took other measures to make the body as light
as possible while confirming body strength.
Structure and equipment
Both cars in the Series EV-E301 two-car trainset have the
same longitudinal seating arrangement with equipment room
at the rear. Each car has seating for 48 passengers with
12-person seats between the three doors on each side.
The seats are cantilever type with heaters and air
conditioning/electrical equipment housed under them,
having independent cover-type risers. Sinuous springs are
used for the seat face to improve cushion comfort. These
springs are integrated into the attachment frames to make
attaching and removing easier. Seat cushions and backs
are bucket type with an effective width of 460 mm to clearly
identify the seat spacing for each passenger.
Interior lights are indirect LEDs to cut power consumption
and give continuous unbroken lighting for the entire length of
the cabin, offering a never-before-achieved cabin image.
The side ceilings have a new three-fold cross sectional
shape with a design aspect of one face being black with a
washi Japanese paper feel. Cabin decorative panels are
As a measure to further enhance accessibility functions,
an LCD fare display that also serves as an on-board guide
for information such as the next station is located at the
top centre of the wall behind the driver’s cab. A chime
sounds when doors open and close and a red lamp flashes,
giving guidance to passengers with vision and hearing
impairments. The door side edges also use yellow doorstop
rubber to make doors more visible from both inside and
outside the train.
Hand straps and luggage racks are 50-mm lower at
part of the front 12 seats, which include priority seats,
allowing easier access by shorter passengers. Moreover
the stanchion poles in the priority seat area have a curved
shape and non-slip surface, making them easier to use.
Aluminium round pipes are used for the luggage racks to
make them lighter.
A wheelchair space at the back end features an emergency intercom at a level where passengers can
communicate with crew while seated in a wheelchair.
Windows and doors
The side windows are separated into top and bottom sections
with the top section able to slide down to open. Sufficient
window area was secured by combining with fixed windows.
The windows use UV-absorbent glass; FRP window frame
covers are set on the interior side of side windows.
The side sliding doors use stainless steel panels on both
the interior and exterior, with a honeycomb core between
them for lightness and strength. The effective width of the
doors is 1300 mm.
The end sliding doors at the gangway between cars
close naturally thanks to tilted door operating equipment.
They have an 800-mm effective width, so wheelchair users
can pass through, taking into account limited door operation
by one-person crew.
The only crew cabin is the one-person operation driver’s
cab with no corridor connection to the passenger cabin.
To protect the driver in an impact, the body front has a reinforced structure as well as a rescue port behind the cab.
The Series EV-E301 has new switches required by a
catenary and battery-powered hybrid railcar, such as
quick-charge switches, as well as equipment for identifying
the type of overhead catenary. They are arranged to help
prevent driver error.
The front window glass is partitioned into two parts with
a 2:1 ratio for the driver’s side and assistant’s side, taking
maintainability into account. It is vertically curved large
quadratic surface glass
The front marker lights use LEDs located on the top front
with two each on the left and right sides. The rear marker
lights are placed vertically at the bottom rear to give a
Under-floor equipment layout
Auxiliary power sources and related equipment along with
electric compressor units are installed on car No. 1, and
traction circuit-related equipment, such as power converters,
is installed on car No. 2. A total of 10 battery boxes for the
traction circuit are located in groups of five in each car.
Rooftop equipment layout
Two pantographs supporting quick charging are installed on
car No. 2. Both cars have air conditioners and train radios.
Main controller and auxiliary power source
DC/DC converters are located under the pantographs to
convert the 1500-Vdc overhead line voltage to 630 Vdc.
Large-capacity lithium-ion batteries are located in the
630-Vdc intermediary link circuit as traction circuit batteries,
and there is also a VVVF inverter and two auxiliary induction
motors with 630-Vdc input. Moreover, the auxiliary power
source primarily runs on power from the traction circuit
batteries. The intermediary link circuit is 630 Vdc to secure
safety with the lithium-ion batteries. The Series EV-E301 is
a two-car trainset, so a two-group structure is installed to
ensure redundancy for the traction circuit system.
Since the intermediary link circuit is 630 Vdc, the VVVF
inverter and induction motors are not the same type as
used by ordinary EMUs running off 1500-Vdc overhead
catenary. During the design stage, we considered a
system where the intermediary link circuit was 1500 Vdc and a DC/DC converter was located upstream from the
batteries, but the current system was used so as not to
reduce the limited power from the battery energy through
The drive method with this system differs in electrified
and non-electrified sections. At power running on nonelectrified
sections, motive power is generally electric power
from batteries. On electrified sections, the train receives
electric power from the overhead catenary while running on
electric power from the batteries, so the actual battery state
of charge (SOC) does not fluctuate very much.
Regenerative energy from braking is generally stored
in the batteries but when the batteries are fully charged, it
is returned to the overhead catenary in the same way as an
At power running on non-electrified sections,
regenerative energy from braking is stored in the batteries
and subsequently used as energy for motive power.
The traction circuit performance offers a starting
acceleration of 2.0 km/h/s, giving acceleration equivalent
to limited-express trains. The maximum speed on the
Karasuyama Line is 50 to 60 km/h, but is 100 km/h on the
Utsunomiya Line. Two-level inverters are used for the DC/DC converter and VVVF inverter to increase quality by reducing
the number of elements. The DC/DC converter and VVVF
inverter have an integrated chassis structure to make the
devices more compact. Inverter equipment is cooled by air
as the train moves, but the DC/DC converter has cooling fins
to allow sufficient cooling when the train is stopped at quick
charging and there is no air flow.
The main motor is a three-phase squirrel-cage open type
induction motor. An ordinary EMU induction motor cannot be
used because the inverter voltage is 630 Vdc. Consequently,
we used the same induction motor as used on Type Kiha
E200 hybrid railcars with similar battery voltage, and worked
to make the equipment common between the two.
Batteries (for motive power)
Battery energy is important with the Series EV-E301, so
we decided to use lithium-ion batteries with higher energy
density, although the power is weaker than using capacitors.
630 Vdc is supplied from 22 traction circuit batteries in
series; arranging 10 banks of these in parallel achieves
190 kWh. Each bank is housed in one box, and a total of 10 boxes are installed under the floor.
The capacity was designed to give leeway in terms of
charge failure in addition to energy consumed when running,
taking into account situations that might occur, such as
To ensure a high safety level for the lithium-ion batteries,
the double protection of a battery controller and power
converter controller was provided in addition to a structure to
prevent battery box rupture in an accident.
Power collection device
A single arm design was adopted for the two pantographs;
they feature strengthened contact strips to handle the
large current at quick charging. Moreover, the pantograph
horn is painted fluorescent green to give distinctive design
characteristics and to increase visibility at night.
The braking system uses electric-command brake
equipment combined with regenerative braking equipment.
There are five types of brakes: service, emergency, straight
air reserve, snowproof, and holding. Each bogie has one
Service brakes control each car. By performing electropneumatic
cooperative control where the trailing bogie
braking power is supported as much as possible by the
motored bogie regenerative braking, regenerative energy is
increased and brake shoe wear is reduced.
To prevent increased braking distance and wheel flat
generation due to sliding when braking, wheel slide readhesive
control is provided. Each axle has a tachometer
generator to detect speed and if sliding is detected, braking
power to the sliding axle is temporarily weakened to promote
As a feature of the Series EV-E301, emergency
braking is applied based on the overhead catenary status
determined by the equipment for identifying the type of
overhead catenary to prevent entry into non-electrified
sections while the pantographs are raised, and movement of
the train during quick charging.
Air conditioner and heater
One 33,000-kcal/h air conditioner is mounted on the
roof. Sheathed-wire type heaters are located in the
passenger cabin longitudinal seat area and wall area of
the wheelchair space.
The air conditioning is controlled manually from
the monitor screen by selecting heating, cooling, or
ventilation. However, when heating or cooling is set,
output is selected automatically to maintain the base
temperature set for the cabin.
Door operating equipment
The door equipment is a directly operated pneumatic type
with a semi-automatic function. At door closing, the closing
force is weakened temporarily after closing to allow easy
removal of hands, fingers, clothing, bags, etc., that may be
trapped in the door.
The monitoring device supports the driver’s management of
the catenary and battery-powered hybrid railcar system.
The energy flow screen shows the state of the batteries,
and the driver can visualize the flow from the pantograph
through the static converter as well as battery charging
and running of the motors through the inverter. Energy flow
can be confirmed at power running, coasting, braking, and
stopping, and the battery charge, and overhead line type,
are also displayed.
The monitoring equipment is also compatible with
conventional-line digital radio applications, including
operation information and rolling stock information display,
crew support functions such as one-person crew operation
device control, control functions for service equipment such
as coolers and heaters, and inspection/repair functions
related to failure recording and testing.
Train protection system
The trains are equipped with the ATS-P train protection
system. It sends information on overhead catenary status
according to the running location from the wayside to the
equipment to identify the type of overhead line.
Train destination indicators and cabin guidance displays
Train destination indicators use three-colour graphic LEDs
installed at both the front and sides.
There are no cabin guidance displays. The next station,
destination station, side with opening doors, operation
information, etc., are displayed on the LCD fare display
mounted on the wall behind the driver’s cab.
Announcement equipment and emergency intercom
The announcement equipment has functions for making
announcements in the passenger cabin and outside the train.
There is also an automatic system that automatically makes
appropriate announcements at locations where needed.
Emergency intercoms allow two-way passenger
communications with crew. They are located at two positions
in each car, including the wheelchair space.
One-person crew operation equipment
The Series EV-E301 runs with one-person crew on the
Karasuyama Line. Equipment to handle one-person crew
operation includes an outside one-person crew indicator showing passenger doors, in-cabin ticket-issuing machine,
fare box, and LCD fare display (also serving as cabin
guidance display). The outside one-person crew indicator
and ticket-issuing machine are at the two front and back
doors on each side of the car, taking account of the flow of
passengers getting on at the back and off at the front during
The Series EV-E301 bogies are bolster-less with trailing
bogies at the front and powered bogies at the rear.
The wheels are corrugated for the trailing bogies and
solid rolled for the powered bogies. The wheel bearings use
sealed duplex tapered roller bearings.
The power transmission is a parallel cardan-type drive
with main motor and gear units connected by TD joints. The
gear ratio is 6.06.
The car suspension system supports the vertical load
of the body on left and right air springs attached to the
top of the bogie frame. The traction device has a centre
pin attached to the body joined to the bogie frame with a
An axle beam type is used for the axle box suspension.
The brake equipment uses a one-sided tread block and
disk brakes for the trailing bogie, and a one-sided tread
block for the powered bogie.
The lead axle has a ceramic jet ting device for
The Series EV-E301 function has been confirmed by
performance tests and charging tests, and its crew made
training runs before the start of commercial operation using
one trainset of pre-production cars on the Karasuyama Line
on 15 March 2014. We have high hopes that it will be very
popular with users and local residents into the future.
We plan to replace all diesel railcars on the Karasuyama
Line with Series EV-E301 cars sometime in the future.
We are working to improve the battery technology as well
as accelerate our efforts in catenary and battery-powered
H. Abiko, ‘Development of Hybrid Railcars and Catenary and Batterypowered
Hybrid Railcar System,’ JR EAST Technical Review No. 23
M. Shinbo, H. Abiko, H. Sonoda, K. Shibanuma, ‘Utilization of Catenary and
Battery-powered Hybrid train system (4-S7-9),’ Proceedings of the 2013
Japan Industry Applications Society Conference
H. Takiguchi, ‘Overview of Series EV-301 Catenary and Battery-powered
Hybrid Railcar,’ Rolling Stock & Machinery, Japan Railway Rolling Stock &
Machinery Association (May 2014)