IEC TS 62763:2013

IEC/TS 62763 ®
Edition 1.0 2013-12
TECHNICAL
SPECIFICATION
Pilot function through a control pilot circuit using PWM (pulse width modulation)
and a control pilot wire
IEC/TS 62763:2013(E)
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IEC/TS 62763 ®
Edition 1.0 2013-12
TECHNICAL
SPECIFICATION
Pilot function through a control pilot circuit using PWM (pulse width modulation)

and a control pilot wire
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
V
ICS 43.120 ISBN 978-2-8322-1281-3

– 2 – TS 62763  IEC:2013(E)
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Control pilot circuit. 7
3.1 General . 7
3.2 Typical pilot electric equivalent circuit . 8
3.3 Simplified pilot electric equivalent circuit . 9
3.4 Other requirements . 9
4 Requirements for parameters . 10
5 Test procedures for immunity of EV supply equipment to wide tolerances on the
pilot wire and the presence of high frequency data signals on the pilot wire . 25
5.1 General . 25
5.2 Constructional requirements of the EV simulator . 25
5.3 Test procedure . 25
5.4 Test list – Oscillator frequency and generator voltage test . 26
5.5 Duty cycle test . 27
5.6 Pulse wave shape test . 27
5.7 Sequences diagnostic – normal charge cycle . 27
5.8 Open earth wire test. 29
5.9 Test of short circuit values of the voltage . 29
5.10 Example of a test simulator of the vehicle (informative) . 29
5.11 Optional hysteresis test . 31
5.11.1 General . 31
5.11.2 Test sequence for hysteresis between states B and C . 32
5.11.3 Test sequence for hysteresis between states C-E, D-E . 32
5.11.4 Test sequence for hysteresis between states C-D . 32

Figure 1 – Typical control pilot electric equivalent circuit . 8
Figure 2 – Simplified control pilot electric equivalent circuit . 9
Figure 3 – State machine diagram for typical control pilot . 15
Figure 4 – State machine diagram for simplified control pilot . 15
Figure 5 – Normal operation cycle. 27
Figure 6 – Simplified control pilot cycle . 28
Figure 7 – Optional charge cycle test . 29
Figure 8 – Example of a test circuit (EV simulator) . 30

Table 1 – Maximum allowable carrier signal voltages on pilot wire . 10
Table 2 – Control pilot circuit parameters (see Figures 1 and 2) . 10
Table 3 – Vehicle control pilot circuit values and parameters . 11
Table 4 – System states detected by the EV supply equipment . 12
Table 5 – State behavior . 14
Table 6 – List of sequences . 16

TS 62763  IEC:2013(E) – 3 –
Table 7 – Pilot duty cycle provided by EV supply equipment . 24
Table 8 – Maximum current to be drawn by vehicle . 24
Table 9 – Test resistance values . 25
Table 10 – Parameters of control pilot voltages. 26
Table 11 – Test parameters of control pilot signals at the measure point according to
Figure 8 . 27
Table 12 – Normal charge cycle test . 28
Table 13 – Position of switches . 31
Table 14 – Initial settings of the potentiometer at the beginning of each test . 31

– 4 – TS 62763  IEC:2013(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PILOT FUNCTION THROUGH A CONTROL PILOT CIRCUIT
USING PWM (PULSE WIDTH MODULATION) AND A CONTROL PILOT WIRE

FOREWORD
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• the required support cannot be obtained for the publication of an International Standard,
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• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC/TS 62763, which is a technical specification, has been prepared by IEC technical
committee 69: Electric road vehicles and electric industrial trucks.
Edition 2 of IEC 61851-1, published in 2010 is presently undergoing revision. This Technical
Specification will be valid until the publication of Edition 3 of IEC 61851-1.
In this document, the numbers in square brackets at the beginning of a sentence, help to
identify requirements.
TS 62763  IEC:2013(E) – 5 –
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
69/242/DTS 69/254/RVC
Full information on the voting for the approval of this technical specification can be found in
the report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• transformed into an International Standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – TS 62763  IEC:2013(E)
INTRODUCTION
The pilot wire function described in this document has been designed as a control mechanism
for the supply of electrical energy to electric vehicles, principally for the charging of the
traction batteries of the vehicle. It concerns all charging systems that ensure the pilot function
with a pilot wire circuit with PWM for mode 2, mode 3 and mode 4 charging as described in
the IEC 61851 series. As indicated in the foreword, Edition 2 of IEC 61851-1, published in
2010 is presently undergoing revision. This Technical Specification will be valid until the
publication of Edition 3 of IEC 61851-1.

TS 62763  IEC:2013(E) – 7 –
PILOT FUNCTION THROUGH A CONTROL PILOT CIRCUIT
USING PWM MODULATION AND A CONTROL PILOT WIRE

1 Scope
This Technical Specification describes the pilot wire function designed as a control
mechanism for the supply of electrical energy to electric vehicles, principally for the charging
of the traction batteries of the vehicle. It concerns all charging systems that ensure the pilot
function with a pilot wire circuit with PWM for mode 2, mode 3 and mode 4 charging as
described in the IEC 61851 series.
This document describes the functions and sequencing of events for this circuit based on the
recommended typical implementation circuit parameters. The parameters indicated also
ensure the interoperability of control pilot wire systems designed according to SAE J1772.
This document is not applicable to vehicles using pilot functions that are not based on a PWM
signal and a pilot wire.
NOTE 1 In the context of this document the words “EV supply equipment” designate any one of the following: the
AC EV supply equipment in mode 3, the in cable control box in mode 2 and/or the DC EV supply equipment in
mode 4.
NOTE 2 The control pilot wire is a supplementary conductor, in addition to the power lines linking the vehicle to EV
supply equipment via the vehicle coupler.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61851-1:2010, Electric vehicle conductive charging system – Part 1: General
requirements
IEC 61851-23 , Electric vehicle conductive charging system – Part 23: D.C. electric vehicle
charging station
ISO/IEC 15118 (all parts), Road vehicles – Vehicle to grid communication interface
3 Control pilot circuit
3.1 General
Two types of pilot functions are possible: simplified and typical.
• Simplified pilot function fulfils the basic requirements that are described in 6.4.1 of
IEC 61851-1:2010.
• Typical pilot function fulfils the basic requirements that are described in 6.4.1 of
IEC 61851-1:2010 and also allows the selection of charging rate as described in 6.4.2.
of IEC 61851-1:2010.
—————————
To be published.
1,3 KΩ
or 270 Ω
2,74 KΩ
– 8 – TS 62763  IEC:2013(E)
Additional requirements for implementation in mode 4 system are described in IEC 61851-23.
Figures 1 and 2 show examples of the principle of operation of the control pilot circuit.
The EV (electric vehicle) supply equipment may cut off the power after at least 5 s in case the
EV will use more current than the duty cycle indicates.
It is recommended to de-energize the system, if the measured current exceeds the current
signalled by duty cycle with a tolerance of 10 %.
[RA03-010] The circuit parameters shall be designed in accordance with Table 2, Table 3
and 3.4.
[RA03-020] The functionality of the pilot line shall follow the requirements defined in
Table 2, Table 6, Table 7, and Table 8.
This information may be provided to the pilot function controller by an energy management
system.
3.2 Typical pilot electric equivalent circuit
Charging side
EV side
Voltage
measurement
(Va)
D
R1 Duty cycle and
Pilot
frequency measurement
contact
(Vb)
1 KΩ
(Vg)
R2
Cv
Cs
Cc
R3
Oscillator S2
±12 V, 1 KHz
Chassis
Earth
(ground)
IEC  2926/13
NOTE Inductive components can be included, but are not shown here.
Figure 1 – Typical control pilot electric equivalent circuit
The EV supply equipment communicates by setting the duty cycle of a PWM signal or a
steady-state DC voltage of the pilot signal, (Table 7 and Table 8).
The EV supply equipment may change the duty cycle of the PWM at any time.
The EV communicates by loading the positive half-wave of the pilot signal.
For further information see also Table 3 and Table 4.
[RA03-030] Typical control pilot (Figure 1) shall support state B.
[RA03-040] Using a typical control pilot, the EV shall follow the PWM, Table 8.
NOTE The designations of R2 and R3 have been exchanged with respect to IEC 61851-1:2010.

882 Ω
or 246 Ω
TS 62763  IEC:2013(E) – 9 –
3.3 Simplified pilot electric equivalent circuit
Charging side
EV side
Voltage
measurement
(Va)
R1 D
Optional
Pilot
Duty cycle and
contact
1 KΩ
frequency measurement
(Vb)
(Vg)
Re
Cv
Cs
Cc
Oscillator
±12 V, 1 KHz
Chassis
Earth
(ground)
IEC  2927/13
NOTE Inductive components can be included, but are not shown here.
Figure 2 – Simplified control pilot electric equivalent circuit
[RA03-050] EVs, designed with simplified circuit, shall be limited to single phase charging
and not exceeding 10 A.
[RA03-060] For a system using the simplified control pilot, the EV supply equipment side
shall modulate the PWM in the same manner as done for a system using a typical control
pilot.
The simplified control pilot circuit gives an equivalent result to the circuit shown in Figure 1 as
if the switch S2 is closed.
[RA03-070] In a simplified pilot circuit, state B does not exist.
[RA03-080] An EV using the simplified control pilot circuit, may measure the duty cycle.
[RA03-090] The EV supply equipment may cut off the power after at least 5 s in case the EV
will use more current than the duty cycle indicates.
It is not recommended to use simplified pilot for new design.
For the EV in new design, it is recommended to follow the PWM.
NOTE In some countries simplified pilot is not allowed: US.

3.4 Other requirements
[RA03-100] Additional components required for signal coupling shall not cause the control
pilot duty cycle signal, to get deformed beyond the limits defined in Table 7 and tested as in
5.5.
[RA03-110] Any impedance inserted in series with the pilot wire, at the EV supply equipment
shall not have a total inductance of more than 1 mH (Lse).
[RA03-120] Any impedance inserted in series with the pilot wire, at the EV shall not have a
total inductance of more than 1 mH (Lsv).
[RA03-130] Any inductive impedance inserted in series with the pilot wire shall be resistively
damped to avoid high frequency oscillation of the PWM signal.

– 10 – TS 62763  IEC:2013(E)
When using high frequency signals for digital communication the following requirements have
to be taken into account.
[RA03-140] The additional signal shall have a frequency of at least 148 kHz.
[RA03-150] The voltage of the high frequency signal shall be in accordance with the values
given in Table 1.
Digital communication standard is described in the ISO/IEC 15118 series.
NOTE One further capacitive (max of 2 000 pF) branch can be used for injection of the additional signals provided
the resistance impedance to ground is greater than 10 kΩ. Such capacitive/resistive branch would typically be used
for signal inputs and automatic signal voltage control (refer to Table 1).

Table 1 – Maximum allowable carrier signal voltages on pilot wire
Frequency (kHz) Max peak/peak voltage (V)
148 to 249 0,4
250 to 499 0,6
500 to 1 000 1,2
> 1 000 2,5
4 Requirements for parameters
Table 2 – Control pilot circuit parameters (see Figures 1 and 2)

a
Parameter Symbol Value Units Remark
Generator open circuit positive Voch V
12 (± 0,6)
c
voltage
Generator open circuit negative Vocl V
−12 (± 0,6)
c
voltage
Frequency generator output Fo 1 000 (± 2%) Hz The EV shall detect the frequency
In case the frequency is outside of 1 kHz the
EV should not charge.
For simplified control pilot this is not
applicable
b c
Pulse width Pwo
Per Table 7 (± 5 μs) μs
c
Maximum rise time (10 % to 90 %) Trg 2
μs
c
Maximum fall time (90 % to 10 %) Tfg 2
μs
Maximum settling time to 95 % Tsg 3
μs
c
steady state
Equivalent source resistance R1
1 000 ± 3 % Ω 970 Ω to 1 030 Ω
1 % equivalent resistors commonly
recommended
d
EV supply equipment capacitance Cs Max 1 600 pF
Min 300
Cable capacitance Cc Max 1 500 pF Case B (cord set)
e
EV capacitance Cv Max 2 400 pF
Stray and additional components
Typical values
Damping resistance Rse, 100 to 1 000 Ω
(may be included in ferrite losses)

TS 62763  IEC:2013(E) – 11 –
Rsv
Optional additional series   Lse 1 mH Maximum value allowed on off board EV
inductance supply equipment
Lsv 1 mH Maximum value allowed on vehicle
NOTE 1 Va can be measured at the pilot terminal of the socket outlet or connector during state A (see Clause 4).
NOTE 2 Cases A to C (as defined in IEC 61851-1) refer to the topology of the charging cable:
– case A: cable permanently attached to the vehicle, fitted with a plug;
– case B: separate cable, fitted with plug and vehicle connector;
– case C: cable permanently attached to the charging post, fitted with a vehicle connector.
a
Tolerances to be maintained over the full useful life and under environmental conditions as specified by the
manufacturer.
b
Measured at 0 V crossing of the 12 V signal.
c
Measured at point Vg as indicated on Figure 1.

d
For case C the max equivalent capacitance is total of Cc + Cs.
e
For case A the max equivalent capacitance is total of Cc + Cv.
[RA04-010] Vehicle control pilot circuit values and parameters as indicated on Figures 1 and

2 are given in Table 3.
Table 3 – Vehicle control pilot circuit values and parameters

Parameter Symbol Value Value range Units
Permanent resistor value R3 2,740 2 658 to 2 822 Ω
Switched resistor value for R2 1,300 1 261 to 1 339
Ω
vehicles not requiring ventilation
State Cx
Switched resistor value for R2 270 261,9 to 278,1
Ω
vehicles requiring ventilation
State Dx
Equivalent total resistor value no Re 882 856 to 908
Ω
ventilation (Figure 2)
State Cx
Equivalent total resistor ventilation Re 246 239 to 253
Ω
required (Figure 2)
State Dx
Diode voltage drop         Vd 0,7 0,55 to 0,85 V
(2,75 mA, to 10 mA, - 40 °C to +
85 °C)
Fast turn-off diode (Tr < 200 ns)
Vr > 50 V
Maximum total equivalent input Cv 2 400 N/A pF
capacitance
[RA04-020] Value ranges shall be maintained over full useful life and under design
environmental conditions.
1 % resistors are commonly recommended for this application.
The Table 4 details the pilot voltage ranges as a result of Tables 2 and 3 components values.
These voltage ranges apply to the EV supply equipment (Va).

– 12 – TS 62763  IEC:2013(E)
Table 4 – System states detected by the EV supply equipment
a f
Va PWM System EV S2 EV EV EV supply Remark
state connected    ready to supply equipment
status
to the EV receive equip- supply

g
supply energy ment energy
Lower Nominal Higher
equipment ready to
level
level (v) supply
h
(v) energy
(v)
d
11 12 13 Off A1 N/A No Not ready Off
no Vb = 0 V
d e i
11 12 13 On A2 No Ready Off
j
10 11 N/A Ax or Bx no/yes open No N/A Off
b
8 9 10 Off B1 No Not ready Off Re = R3 =
open 2,74 kΩ
b e i
8 9 10 On B2 No Ready Off
detected
open/
j
7 8 N/A Bx or Cx N/A State dependent
close
c
5 6 7 Off C1 Yes Not ready Off Re = 882
Ω
detected
Charging
c e,i
5 6 7 On C2 Yes Ready On area
yes ventilation
not
required
close
j
4 5 Off Cx or Dx Yes State dependent
c
2 3 4 Off D1 Yes Not ready Off Re = 246
Ω
detected
Charging
c e i
2 3 4 On D2 Yes Ready On
area
ventilation
required
j
1 N/A 2 N/A Dx or E open State dependent
Vb = 0:
EV supply
equipment
or utility
problem
−1 0 1 Off E N/A N/A No Not ready Off or utility
power not
available
or pilot
short to
earth
EV supply
equipment
−13 −12 −11 Off F N/A N/A No Not ready Off
not
available
Low side
−13 −12 −11 On x2 yes N/A State dependent of PWM
signal
Voltage values, Va, as indicated in the table are informative, actual values to be tested according to Clause 5.

TS 62763  IEC:2013(E) – 13 –
a
All voltages are measured after stabilization period.

b
The EV supply equipment generator may apply a steady state DC voltage or a 12 V square wave during this period.
The duty cycle indicates the available current as in Table 7.

c
The voltage measured is function of the value of R2 in Figure 1 (indicated as Re in Figure 2).

d
12 V static voltage.
e
The EV supply equipment shall check pilot line low state of −12 V, diode presence, at least once before the closing of
the supply switch on the EV supply equipment.

f
S2 = switch contacts in the EV.

g
EV ready to receive energy = EV ready to be charged by closing S2 contacts.

h
EV supply equipment ready to supply energy = ready – PWM on, not ready – PWM off.

i
Negative voltage range tolerances of the PWM are defined by “Low side of PWM signal” row (last row).
j
A control pilot circuit defines its own trigger level to separate the states inside this voltage range. It is recommended

to use different trigger levels depending on the direction of the state change to include hysteresis behaviour.

There is no undefined voltage range, for the control pilot, between the system states.
The state is valid if it is within the above values, the state detection shall be noise resistant,
e.g. against EMC and high frequency data signals on the pilot wire.
NOTE 1 Reliable detection of a state change can require measurements during a few milliseconds or a few PWM
cycles.
[RA04-030]  The EV supply equipment shall verify that the EV is properly connected by
verifying the presence of the diode in the pilot circuit, before energizing the system. This shall
be done at the transition from x1 to x2 or at least once during state x2, before closing the
switching device. Presence of the diode is detected if the low side of the pilot pulse is within
the voltage range defined in Table 4.
[RA04-040] The EV supply equipment shall open or close the switching device within the time
indicated in Table 6.
[RA04-050] When not in State C or D, the EV supply equipment shall open the supply
switching device within 100 ms.
Compliance is tested as in Clause 5.
NOTE 2 The EV supply equipment can attempt to retry the charging sequence in case a valid state is recognized.
NOTE 3 In some countries, in case of a short circuit between the control pilot and earth, a max time of 3 s is
allowed to open the switching device according to SAE J1772:2012: US.
The state changes between A, B, C and D are caused by the EV or by the user.
The state changes between x1 and x2 are created by the EV supply equipment.
A change between state x1 and x2 indicates an unavailability or unavailability of power to the
EV.
– 14 – TS 62763  IEC:2013(E)
Table 5 – State behavior
States Behaviour Remark
a
x1 The EV supply equipment is not If energy is available, the EV
capable to deliver energy, either due supply equipment shall change
b
to the lack of available power in the to x2 . The EV can use this as a
grid, or to the EV supply equipment trigger to start or resume
intentionally stopping for intermittent charging.
charging.
State E No power to the EV supply The EV supply equipment
equipment (e.g. AC voltage outage). unlocks the socket outlet at
maximum of 30 s, if any.
Short circuit of control pilot to PE.
State F Unavailability of the EV supply The EV supply equipment
equipment unlocks the socket outlet at
maximum of 30 s, if any.
(e.g. the EV supply equipment can’t
give service, software upgrade etc.).
a
State x1 can be referred to A1 or B1 or C1 or D1.
b
State x2 can be referred to B2 or C2 or D2.
NOTE 1 In case of a power outage and the EV supply equipment has a backup
battery, it can stay in state x1; after the drainage of the battery, it needs to reach state
E.
NOTE 2 In case of case B and the cable belonging to the EV supply equipment
owner, an unlock is under the EV supply equipment owner's decision.
NOTE 3 In case of state F and the EV supply equipment is able to unlock the socket
outlet via user interaction (e.g. authorisation) there is no need to unlock in 30 s.
It is not recommended to use the F state to signal unavailability of energy to the EV. State x1
gives the same information.
The state E may be caused by any number of difficulties and shall not be used as a signalling
state to convey specific information.
When
...