1
FORM – 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
SYSTEM FOR CONTROLLING AN ERCV IN A HYDROGEN INTERNAL
COMBUSTION ENGINE
Applicant(s):
VE COMMERCIAL VEHICLES LTD
102, INDUSTRIAL AREA 1, PITHAMPUR- 454775, DIST. DHAR, MP, INDIA
Inventors:
1. Narendra Chaudhary
2. Mukesh Gond
3. Aditya Singh
4. Hemant Rathi
5. Sachin Agarwal
The following specification particularly describes the invention and the manner
in which it is to be performed.
2
SYSTEM FOR CONTROLLING AN ERCV IN A HYDROGEN INTERNAL
COMBUSTION ENGINE
FIELD OF THE DISCLOSURE
[0001] The present invention relates generally to the field of automotive electronic
control systems, and more particularly to a system and method for enabling,5
conditioning, and safely controlling an electronically controlled rotary control valve
(eRCV) in hydrogen internal combustion engine (H₂ ICE) application
BACKGROUND OF THE INVENTION
[0002] The subject matter discussed in the background section should not be assumed10
to be prior art merely as a result of its mention in the background section. Similarly, a
problem mentioned in the background section or associated with the subject matter of
the background section should not be assumed to have been previously recognized in
the prior art. The subject matter in the background section merely represents different
approaches, which in and of themselves may also correspond to implementations of the15
claimed technology.
[0003] Conventional systems for controlling electronically controlled rotary control
valves (eRCVs) in internal combustion engines typically rely on multiple discrete
electronic modules, including external DC-DC converters, independent signal
conditioning circuits, separate relay or logic control units, and standalone20
electromagnetic interference (EMI) and surge protection components. In such
architectures, each module performs an isolated function, requiring manual design and
calibration to match high-side Engine Control Unit (ECU) outputs, commonly
operating at 24 V, with low-voltage eRCV logic inputs in the range of 3–5 V. These
solutions are generally derived from petrol or diesel engine control designs and are not25
optimized for the unique operational characteristics of hydrogen internal combustion
engines (H₂ ICE). As a result, these systems demand extensive wiring harnesses
3
between the ECU, DC-DC converter, valve driver, and eRCV, increasing packaging
volume, installation complexity, and dependency on skilled technicians for integration
and tuning.
[0004] Further, the use of external DC-DC converters and discrete conditioning
modules introduces additional failure points, increases susceptibility to voltage5
fluctuations and electromagnetic interference (EMI), and complicates system reliability
in harsh automotive environments. Conventional solutions typically require external or
manual arrangements to implement delay-based braking logic during engine shutdown,
which is critical to prevent abrupt valve stoppage and mechanical stress in hydrogen
combustion systems. Moreover, EMI filtering and surge suppression are often added as10
separate components, further increasing system cost, footprint, and wiring complexity.
Consequently, existing approaches struggle to deliver the precise, stable, and fail-safe
control demanded by modern H₂ ICE platforms under dynamic operating conditions,
highlighting a need for a more integrated, compact, and robust eRCV control solution.
[0005] According to the patent application number “CN119502770A” titled “Control15
system of high-power hydrogen fuel cell”, discloses a control system of a high-power
hydrogen fuel cell, which comprises a box body and a circuit control system in the box
body, and the circuit control system comprises an ECU module, a fuel cell DC/DC
module, a filtering and discharging circuit, an EIS module, an air compressor control
module, a hydrogen circulating pump control module, a step-down DC/DC module, an20
HV-PDU module and an LV-PDU module. The circuit control system is electrically
connected with a plurality of electrical connection interfaces arranged on the box body.
The system simplifies pipeline connection, and is high in integration level, diversified
in function, convenient to use and high in compatibility. However, the reference does
not disclose any dedicated Electronic Rotary Control Valves (eRCV) Interface Unit25
which integrates signal conditioning, DC-DC converter, voltage translation, built-in
fault protection, EMI filtering or adapt ECU high-side output (24V) to eRCV low-
voltage input (5V). Further, the reference also fails to disclose any eRCV interface
4
circuit that incorporates a programmable delay logic after ECU “off” signal to
maintain eRCV hold for a defined time.
[0006] According to another patent application number “US10538154B2” titled
“Smart active mount”, discloses a smart active mount apparatus configured for
removing a complicated wiring for connecting a controller, a mount, and an engine5
ECU, a vacuum negative pressure hose, and a controller may include an insulator
disposed in a case to define a liquid chamber; a lower orifice plate disposed in the case
to partition the liquid chamber into upper and lower liquid chamber; an upper orifice
plate disposed above the lower orifice plate; a membrane disposed between the lower
and upper orifice plates; a diaphragm disposed under the lower orifice plate, an air10
chamber defined between the membrane and the lower orifice plate; a solenoid valve
connected to the air chamber; and a generator disposed to the diaphragm, the generator
generating electrical energy by movement or deformation of the diaphragm to supply
the electrical energy as actuating power of the solenoid valve. However, the reference
does not disclose any dedicated Electronic Rotary Control Valves (eRCV) Interface15
Unit which integrates signal conditioning, DC-DC converter, voltage translation,
built-in fault protection, EMI filtering or adapt ECU high-side output (24V) to eRCV
low-voltage input (5V). Further, the reference also fails to disclose any eRCV
interface circuit that incorporates a programmable delay logic after ECU “off” signal
to maintain eRCV hold for a defined time.20
[0007] The cited prior arts, either individually or in combination, do not adequately
address the technical requirements of a dedicated eRCV enable interface system for
hydrogen internal combustion engine applications. In particular, the prior arts fail to
disclose or suggest a unified, single-module interface that integrates DC-DC power
conversion, ECU high-side (24 V) to eRCV low-voltage (3–5 V) signal translation,25
enable signal conditioning, speed signal buffering, EMI filtering, built-in fault
protection, and ground reference management within a compact PCB-mounted unit.
Further, the cited references do not teach or contemplate a solution that operates directly
5
with existing ECU outputs without firmware modification, nor do they disclose any
programmable delay or power-hold logic configured to maintain eRCV operation for a
defined duration after an ECU OFF command to enable controlled rotor deceleration,
which is critical for hydrogen combustion safety. As a result, existing solutions remain
fragmented, rely on multiple discrete components, increase wiring complexity and5
failure points, and lack hydrogen-specific fail-safe control behavior. Therefore, there
exists a need for an improved, integrated eRCV interface system and method that
provides reliable, safe, and manufacturable control of eRCVs under real-world
hydrogen engine operating conditions, while reducing system complexity, cost, and
installation effort.10
OBJECTIVES OF THE INVENTION
[0008] An objective of the invention is to provide a system for controlling an
electronically controlled rotary control valve (eRCV) in a hydrogen internal
combustion engine.
[0009] Furthermore, the objective of the invention is to provide a method for15
controlling an electronically controlled rotary control valve (eRCV) in a hydrogen
internal combustion engine.
[0010] An objective of the invention is to provide all in one system that integrates
power conversion, control logic, and signal interfacing within a single compact unit to
eliminate the need of multiple discrete modules and simplifying system architecture in20
hydrogen internal combustion engine (H₂ ICE) applications.
[0011] Furthermore, the objective of invention is to provide system that is capable of
adapting high-side ECU control signals to low-voltage eRCV logic levels to ensure
accurate and noise-immune communication without requiring any modification to
existing ECU firmware.25
6
[0012] Furthermore, the objective of the present invention is to provide a system the
maintains eRCV operation for a predefined duration after engine shutdown to enable
safe and controlled rotor deceleration and preventing abrupt mechanical stoppage.
[0013] Furthermore, the objective of the present invention is to provide a system that
minimize wiring harness complexity by consolidating power, control, and signal5
interfacing functions into a single module to reduce installation effort, potential failure
points, and overall system cost.
SUMMARY
[0014] The invention relates to a system for controlling an electronically controlled
rotary control valve (eRCV) in a hydrogen internal combustion engine.10
[0015] According to an aspect, system for controlling an electronically controlled
rotary control valve (eRCV) in a hydrogen internal combustion engine is disclosed.
Further, the system comprises a vehicle electrical power source configured to provide
a nominal 24 V DC supply. Further, an engine control unit (ECU) comprising a high-
side enable output configured to selectively output an ON/OFF control signal at15
approximately 24 V D, and a frequency-based speed signal output represents an engine
or rotor speed. Further, a power hold relay having a coil and switched contacts, the
switched contacts being connected between the vehicle electrical power source and a
power input of the eRCV. Further, a eRCV unit comprises a power input terminal, a
ground terminal, an enable input terminal, and a speed signal input terminal. Further,20
eRCV enable coupling device electrically coupled to the RCU, the power hold relay
and the eRCV unit, wherein the eRCV enable coupling device is configured to receive
the 24 V high-side enable signal from the ECU via a pin 1. Further, convert the received
24V high-side enable signal into a regulated logic-level enable signal in a range 0-5 V
suitable for direct connection to the eRCV enable input terminal (i.e. pin 3). Further,25
derive at least one regulated low-voltage supply from the 24 V vehicle power source
for the eRCV enable coupling device, via an integrated DC-DC convertor. Further,
7
receive a frequency-based speed signal from the ECU and output a buffered speed
signal to the speed signal input terminal of the eRCV (i.e pin 4). Further, provide a
stable and noise- controlled ground reference between the ECU and the eRCV unit via
a pin 2. Further, maintain energization of the power hold relay and the enable signal to
the eRCV for a predefined time interval after the ECU high-side enable output5
transitions to an OFF state, such that the eRCV remains powered and enabled for
controlled rotor deceleration in hydrogen combustion operation.
[0016] According to another aspect, a method for controlling an electronically
controlled rotary control valve (eRCV) in a hydrogen internal combustion engine is
disclosed. Further, the method comprising supplying a nominal 24 V DC vehicle power10
to an ECU and to a power hold relay connected in series with a power input of the
eRCV unit. Further, generating, by the ECU, a high-side enable signal at approximately
24 V DC corresponding to a commanded ON state of the eRCV unit. Further, receiving
the high-side enable signal at an eRCV enable coupling device positioned electrically
between the ECU and the eRCV unit. Further, filtering and protecting the received high-15
side enable signal to suppress electrical noise, voltage transients, and electromagnetic
interference. Further, translating the high-side enable signal from approximately 24 V
DC into a regulated logic-level enable signal in a range of 0–5 V compatible with an
enable input of the eRCV unit. Further, supplying the translated logic-level enable
signal to the enable input of the eRCV unit to permit rotary valve operation. Further,20
receiving, at the eRCV enable coupling device, a frequency-based speed signal from
the ECU representing engine or valve rotational speed. Further, buffering the
frequency-based speed signal to improve signal integrity and electromagnetic
immunity. Further, transmitting the buffered speed signal from the eRCV enable
coupling device to a speed signal input of the eRCV unit. Further, generating, within25
the eRCV enable coupling device, at least one regulated low-voltage supply from the
24 V vehicle power using an integrated DC-DC converter to power internal logic and
signal conditioning circuits and upon transition of the ECU high-side enable signal to
8
an OFF state, maintaining energization of the power hold relay and the enable signal to
the eRCV unit for a predefined time interval, thereby allowing controlled deceleration
of an eRCV rotor in hydrogen combustion operation.
9
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The accompanying drawings illustrate the embodiment of the system. Any
person with ordinary skills in the art will appreciate that the illustrated element
boundaries (e.g., boxes, groups of boxes, or other shapes) in the figures represent one
example of the boundaries. It may be that in some examples one element may be5
designed as multiple elements or that multiple elements may be designed as one
element. In some examples, an element shown as an internal component of one element
may be implemented as an external component in another, and vice versa. Furthermore,
elements may not be drawn to scale. Non-limiting and non-exhaustive descriptions are
described with reference to the following drawings. The components in the figures are10
not necessarily to scale, emphasis instead being placed upon illustrating principles.
[0019] FIG. 1 illustrates a block diagram of a system for controlling an electronically
controlled rotary control valve (eRCV) in a hydrogen internal combustion engine,
according to an embodiment of the present invention.
[0020] FIG. 2 illustrates a circuit diagram of an eRCV enable coupling device,15
according to an embodiment of the present invention.
[0021] FIG. 3 illustrates a flow chart of a method for operating the system for
controlling an electronically controlled rotary control valve (eRCV) in a hydrogen
internal combustion engine, according to an embodiment of the present invention.
20
10
DETAILED DESCRIPTION OF THE INVENTION
[0023] Some embodiments of this disclosure, illustrating all its features, will now be
discussed in detail. The words “comprising,” “having,” “containing,” and “including,”
and other forms thereof, are intended to be equivalent in meaning and be open ended in
that an item or items following any one of these words is not meant to be an exhaustive5
listing of such item or items or meant to be limited to only the listed item or items. It
must also be noted that as used herein and in the appended claims, the singular forms
“a,” “an,” and “the” include plural references unless the context clearly dictates
otherwise.
[0024] Although any systems and methods similar or equivalent to those described10
herein can be used in the practice or testing of embodiments of the present disclosure,
the preferred, systems and methods are now described. Embodiments of the present
disclosure will be described more fully hereinafter with reference to the accompanying
drawings in which like numerals represent like elements throughout the several figures,
and in which example embodiments are shown. Embodiments of the claims may,15
however, be embodied in many different forms and should not be construed as limited
to the embodiments set forth herein. The examples set forth herein are non-limiting
examples and are merely examples among other possible examples.
[0025] The present invention discloses a system for controlling an electronically
controlled rotary control valve (eRCV) in a hydrogen internal combustion engine.20
[0026] FIG. 1 illustrates a block diagram of a system (100) for controlling an
electronically controlled rotary control valve (eRCV) in a hydrogen internal
combustion engine, according to an embodiment of the present invention.
[0027] In some embodiments, the system (100) for controlling an electronically
controlled rotary control valve (eRCV) in a hydrogen internal combustion engine25
comprises vehicle electrical power source (102), electronic control unit (ECU) (104),
power hold relay (106), eRCV unit (108), and eRCV enable coupling device (110).
11
[0028] In some embodiments, the vehicle electrical power source (102) is configured
to supply a nominal 24 V DC electrical output, as commonly employed in commercial
and heavy-duty vehicle platforms, and serves as the primary power input for the eRCV
control system (100). The vehicle electrical power source (102) provides electrical
energy to the engine control unit (ECU) (104), the eRCV enable coupling device (110),5
and associated components such as the power hold relay (106).
[0029] In some embodiments, the engine control unit (ECU) (104) comprising a high-
side enable output configured to selectively output an ON/OFF control signal at
approximately 24 V DC. Further, the ECU (104) comprises a high-side enable output
configured to selectively generate an ON/OFF control signal at approximately 24 V10
DC, which functions as a command signal for enabling or disabling operation of the
electronically controlled rotary control valve (eRCV) unit (108).
[0030] In some embodiments, the ECU (104) further comprises a frequency-based
speed signal output that represents the operating speed of the engine or the rotational
speed of the eRCV rotor, typically in the form of a pulse or square-wave signal whose15
frequency corresponds to the measured speed. Together, these outputs allow the ECU
(104) to provide both binary control and real-time operational feedback signals required
for coordinated and accurate control of the eRCV under dynamic engine operating
conditions.
[0031] In some embodiments, the power hold relay (106) having a coil and switched20
contacts, the switched contacts being connected between the vehicle electrical power
source (102) and a power input of the eRCV unit (108). In some embodiments, the
power hold relay (106) comprises an electromagnetic coil and the set of switched
contacts. Further, the switched contacts are electrically connected between the vehicle
electrical power source (102) and a power input of the electronically controlled rotary25
control valve (eRCV) unit (108). Upon energization of the coil, the switched contacts
close to supply electrical power from the vehicle power source to the eRCV to enable
normal valve operation. The power hold relay (106) further functions as a controllable
12
power isolation element that allows the eRCV unit (108) to remain powered for a
defined duration when required, such as during engine shutdown, thereby supporting
controlled operation and safe deceleration of the eRCV rotor before complete power
removal.
[0032] In some embodiments, the eRCV unit (108) comprises a power input terminal,5
a ground terminal, an enable input terminal, and a speed signal input terminal. Further,
the power input terminal configured to receive operating electrical power from the
vehicle electrical system (100). Further, the ground terminal provides a return path for
electrical current. Further, the enable input terminal configured to receive a logic-level
control signal that activates or deactivates valve operation. Further, the speed signal10
input terminal configured to receive a frequency-based signal corresponding to engine
or rotor speed. The terminals collectively enable the eRCV unit (108) to be powered,
controlled, and synchronized with engine operating conditions, allowing precise and
reliable valve actuation within the hydrogen internal combustion engine system (100).
[0033] In some embodiments, the eRCV enable coupling device (110) electrically15
coupled to the ECU (104), the power hold relay (106) and the eRCV unit (108). Further,
the eRCV enable coupling device (110) is configured to receive the 24 V high-side
enable signal from the ECU (104) via a pin 1. The eRCV enable coupling device (110)
is configured to receive the 24 V ON/OFF high-side enable signal from the ECU (104)
through Pin 1 of the eRCV enable coupling device (110). The high-voltage control20
signal is processed within the eRCV enable coupling device (110) by an internal signal
conditioning and level-shifting circuit, which converts the 24 V signal into a stable 0–
5 V logic-level enable signal suitable for the enable input of the eRCV at Pin 3 (i.e.
enable input terminal). The eRCV enable coupling device (110) further provide proper
voltage compatibility and timing alignment between the high-side ECU output and the25
low-voltage logic requirements of the eRCV unit (108) by filtering transients,
suppressing noise, and controlling signal rise and fall characteristics to enable reliable
13
and safe activation and deactivation of the eRCV unit (108) under dynamic hydrogen
engine operating conditions.
[0034] In some embodiments, the eRCV enable coupling device (110) is configured to
derive at least one regulated low-voltage supply from the 24 V vehicle power source
for the eRCV enable coupling device (110), via an integrated DC-DC convertor. The5
eRCV enable coupling device (110) is configured to derive at least one regulated low-
voltage power supply from the 24 V vehicle electrical power source (102) through an
integrated DC-DC converter housed within the eRCV enable coupling device (110).
The integrated DC-DC converter steps down the nominal 24 V input to one or more
stable low-voltage levels, such as 5 V and/or 12 V, required for powering internal10
control logic, signal conditioning circuits, and protection elements of the eRCV enable
coupling device (110). By integrating the DC-DC converter within the eRCV enable
coupling device (110), the system (100) ensures consistent voltage regulation,
improved immunity to load variations and electrical noise, and eliminates the need for
external power conversion modules to enhance reliability, reducing wiring complexity,15
and enable compact installation within the engine bay.
[0035] In some embodiments, the eRCV enable coupling device (110) is configured to
receive a frequency-based speed signal from the ECU (104) and output a buffered speed
signal to the speed signal input terminal of the eRCV unit (108) (i.e pin 4). The eRCV
enable coupling device (110) is configured to receive a frequency-based speed or RPM20
signal from the ECU (104). The signal has a frequency of up to approximately 168 Hz,
corresponding to the operational speed range of the engine or the eRCV rotor. The
frequency-based input signal in a range from 0 Hz to about 168 Hz, corresponding to
an engine speed of up to approximately 1000 RPM. The incoming speed signal is
processed through an internal buffering and signal conditioning circuit within the eRCV25
enable coupling device (110) that stabilizes signal amplitude, sharpens signal edges,
and suppresses electrical noise and electromagnetic interference. The conditioned and
buffered speed signal is then transmitted reliably to the speed signal input terminal of
14
the eRCV unit (108), namely Pin 4 to ensure accurate speed representation and maintain
signal integrity under harsh automotive and hydrogen engine operating environments.
[0036] In some embodiments, the eRCV enable coupling device (110) is configured to
provide a stable and noise- controlled ground reference between the ECU (104) and the
eRCV unit (108) via a pin 2 (i.e., GND Reference). The eRCV enable coupling device5
(110) configured to provide a stable and noise-controlled ground reference between the
ECU (104) and the electronically controlled rotary control valve (eRCV) unit (108)
through Pin 2 of the eRCV enable coupling device (110). The Pin 2 is referring as
dedicated ground path that is common to both the ECU (104) side and the eRCV unit
(108), while being internally conditioned within the eRCV enable coupling device10
(110) to maintain controlled impedance or isolation as required. The arrangement
ensures that both the ECU (104) and the eRCV unit (108) operate with a consistent
ground reference to prevent ground loops and reduce differential noise that may
otherwise distort low-voltage enable and speed signals.
[0037] In some embodiments, the eRCV enable coupling device (110) is configured to15
maintain energization of the power hold relay (106) and the enable signal to the eRCV
unit (108) for a predefined time interval after the ECU (104) high-side enable output
transitions to an OFF state, such that the eRCV unit (108) remains powered and enabled
for controlled rotor deceleration in hydrogen combustion operation. By keeping the
power hold relay (106) and enable signal active for a predefined interval that is at least20
five seconds may ensure that the eRCV unit (108) remains powered and operational for
a short period beyond the initial shutdown command. The functionality is critical during
hydrogen combustion operation, where sudden loss of eRCV unit (108) control may
lead to unsafe rotor dynamics or uncontrolled system behavior.
[0038] In conjunction with the power hold relay (106), the eRCV enable coupling25
device (110) implements proper braking logic, allowing the rotor to decelerate safely
according to predefined operational requirements. By preventing abrupt disabling of
the eRCV unit (108), it ensures that the braking sequence occurs in a controlled manner,
15
reducing mechanical stress and enhancing overall system reliability. The eRCV enable
coupling device (110) acts as a safeguard to ensure that power and control are sustained
just long enough to allow safe rotor slowdown without compromising system integrity.
[0039] In some embodiments, the eRCV enable coupling device (110) is further
equipped with protection features to enhance its reliability and robustness in operation.5
The features include electromagnetic interference (EMI) filtering, electrostatic
discharge (ESD) protection, and transient voltage suppression (TVS), either
individually or in combination. EMI filtering prevents unwanted electrical noise from
affecting the device’s operation, ESD protection safeguards the circuitry from sudden
static discharges, and TVS mitigates voltage spikes that could damage sensitive10
components. Together, these protective measures ensure stable and safe performance
of the eRCV enable coupling device (110) under challenging electrical and
environmental conditions.
[0040] FIG. 2 illustrates a circuit diagram (200) of the eRCV enable coupling device
(110), according to an embodiment of the present invention.15
[0041] In some embodiments, the circuit diagram (200) illustrates the overall electrical
interconnection and functional role of the eRCV enable coupling device (110) between
the ECU (104) and the eRCV unit (108) in the hydrogen internal combustion engine
system (100). As shown, a vehicle battery providing a nominal 24 V DC supply feeds
both the ECU (104) and a power hold relay (106). The power hold relay (106) is placed20
in series between the vehicle battery and the power input of the eRCV unit (108),
allowing controlled delivery of power to the eRCV unit (108). The power hold relay
(106) is configured to remain energized for a defined duration such as approximately
five seconds after the ECU (104) enable signal is turned OFF to ensure safe rotor
deceleration before complete power removal.25
[0042] On the control side, the ECU (104) outputs the 24 V high-side ON/OFF enable
signal, which is routed to the eRCV enable coupling device (110) through the dedicated
input pin. Within the eRCV enable coupling device (110), the high-voltage signal is
16
conditioned and level-shifted to a 0–5 V logic-level enable signal, which is then
delivered to the enable input pin (Pin 3) of the eRCV unit (108), as shown in FIG. 2.
This ensures voltage compatibility and correct timing between the ECU (104) and the
low-voltage logic circuitry of the eRCV unit (108). In parallel, the ECU (104) also
provides the frequency-based speed or RPM signal, shown in the FIG. 2 as the separate5
signal path, which is routed through the eRCV enable coupling device (110) where it is
buffered and conditioned before being supplied to the speed signal input (Pin 4) of the
eRCV unit (108) to maintain signal integrity and EMI immunity.
[0043] The FIG. 2 further shows a dedicated ground connection (Pin 2) managed by
the eRCV enable coupling device (110) to provide the stable and noise-controlled10
ground reference shared between the ECU (104) and the eRCV unit (108). The ground
management prevents ground loops and minimizes differential noise, which is critical
for reliable low-voltage signal operation.
[0044] In some embodiments, the FIG. 2 demonstrates how the eRCV enable coupling
device (110) consolidates power conversion, signal conditioning, ground management,15
and fail-safe power-hold control into a single module to reduce wiring complexity,
improve reliability, and enable safe and precise eRCV operation in hydrogen engine
environments.
[0045] FIG. 3 illustrates a flow chart of a method (300) for operating the system (100)
for controlling an electronically controlled rotary control valve (eRCV) in a hydrogen20
internal combustion engine, according to an embodiment of the present invention.
[0046] At operation 302, the nominal 24 V DC vehicle power is supplied to an ECU
(104) and to a power hold relay (106) connected in series with the power input of the
eRCV unit (108). Supplying the nominal 24 V DC vehicle power involves providing
electrical energy from the vehicle electrical system (100) to both the ECU (104) and25
the power hold relay (106) that is connected in series with the power input of the eRCV
unit (108). In the arrangement, the ECU (104) receives continuous operating power for
generating control and speed signals, while the power hold relay (106) selectively
17
controls the delivery of the same 24 V supply to the eRCV unit (108). When the power
hold relay (106) is energized, the switched contacts close to allow the 24 V vehicle
power to reach the eRCV unit (108), enabling normal valve operation.
[0047] At operation 304, the ECU (104) is configured to generate a high-side enable
signal at approximately 24 V DC corresponding to a commanded ON state of the eRCV5
unit (108). The high-side enable signal represents an active control state in which the
ECU (104) sources current at the nominal 24 V level to indicate that the eRCV unit
(108) is permitted to operate. The signal serves as a clear and robust ON/OFF command
suitable for automotive environments, providing sufficient voltage margin and noise
immunity, while being subsequently processed by downstream interface circuitry to10
ensure compatibility with the low-voltage logic requirements of the eRCV unit (108).
[0048] At operation 306, the high-side enable signal is received at the eRCV enable
coupling device (110) positioned electrically between the ECU (104) and the eRCV
unit (108). The eRCV enable coupling device (110) functions as an interface that
intercepts the approximately 24 V DC enable signal before it reaches the eRCV unit15
(108) to allow the high-side enable signal to be processed, conditioned, and adapted to
the electrical requirements of the eRCV unit (108). By receiving the enable signal at
this intermediate interface, the system (100) may ensure controlled signal translation,
protection, and timing management to enable reliable and safe communication between
the ECU (104) and the eRCV unit (108) under varying automotive and hydrogen engine20
operating conditions.
[0049] At operation 308, the received high-side enable signal is filtered and protected
to suppress electrical noise, voltage transients, and electromagnetic interference. This
is achieved through the use of integrated protection and filtering elements such as
transient voltage suppressors, EMI filters, and surge protection circuits, which25
condition the incoming 24 V signal before further processing. The eRCV enable
coupling device (110) ensures that only a clean and stable control signal is passed to
subsequent voltage translation and logic circuits by attenuating high-frequency noise
18
and limiting voltage spikes to prevent false triggering, signal distortion, and potential
damage to sensitive low-voltage components of the eRCV unit (108).
[0050] At operation 310, the high-side enable signal is translated from approximately
24 V DC into a regulated logic-level enable signal in a range of 0–5 V compatible with
an enable input of the eRCV unit (108). The voltage translation is performed using an5
internal level-shifting and regulation circuit that precisely limits the output voltage,
stabilizes signal levels, and protects the eRCV input from over-voltage conditions.
[0051] At operation 312, the translated logic-level enable signal is supplied to enable
input of the eRCV unit (108) to permit rotary valve operation. The translated logic-level
enable signal, having a regulated voltage in the range of 0–5 V, is supplied from the10
eRCV enable coupling device (110) to the enable input of the eRCV unit (108). Upon
receipt of this enable signal, the eRCV transitions from a disabled state to an active
operating state to permit controlled rotation and actuation of the valve in accordance
with engine operating requirements.
[0052] At operation 314, the eRCV enable coupling device (110) is configured to15
receive a frequency-based speed signal from the ECU (104) representing engine or
valve rotational speed. The frequency based speed signal is typically provided as a pulse
or square-wave signal whose frequency varies in proportion to the measured rotational
speed. By receiving the frequency based speed signal, the eRCV enable coupling device
(110) is able to process and condition speed-related information required for20
synchronized operation of the eRCV to enable monitoring and coordination of valve
behavior with engine operating conditions under dynamic hydrogen combustion
environments.
[0053] At operation 316, the frequency-based speed signal is buffered to improve
signal integrity and electromagnetic immunity. The buffering operation stabilizes the25
signal amplitude, sharpens signal transitions, and isolates the ECU (104) output from
downstream electrical loading effects to prevent signal degradation over wiring
harnesses.
19
[0054] At operation 318, the buffered speed signal is transmitted from the eRCV enable
coupling device (110) to the speed signal input of the eRCV unit (108). By driving the
speed signal through a low-impedance buffered output, the eRCV enable coupling
device (110) maintains consistent signal amplitude and frequency fidelity while
minimizing distortion, attenuation, or interference during transmission.5
[0055] At operation 320, the eRCV enable coupling device (110) is configured to
generate at least one regulated low-voltage supply from the 24 V vehicle power using
an integrated DC-DC converter to power internal logic and signal conditioning circuits.
The DC-DC converter steps down the high vehicle voltage to a stable low-voltage level,
such as 5 V or 3.3 V, while providing isolation, voltage regulation, and protection10
against load variations, transients, and electrical noise commonly present in automotive
environments.
[0056] At operation 322, upon transition of the ECU (104) high-side enable signal to
an OFF state, maintaining energization of the power hold relay (106) and the enable
signal to the eRCV unit (108) for a predefined time interval, thereby allowing controlled15
deceleration of an eRCV rotor in hydrogen combustion operation.
[0057] In some embodiments, the present invention is applicable to automotive control
systems for hydrogen internal combustion engines using electronically controlled rotary
control valves (eRCVs). Further, it provides an integrated interface for power
conversion, signal conditioning, and control. The system (100) converts high-voltage20
ECU signals, typically 24 V, into regulated low-voltage levels such as 5 V or 12 V
required by the eRCV, thereby enabling seamless electrical compatibility without
external converters. The present invention further enhances operational safety by
maintaining eRCV activation for a predefined duration after ignition-off to allow
controlled rotor braking, which is especially critical in hydrogen engine applications.25
By integrating DC-DC conversion, signal conditioning, relay control, and protection
circuitry into a single compact unit, the present invention significantly reduces wiring
complexity, installation effort, and failure points, while improving system reliability
20
and saving space. Additionally, the system (100) operates in a plug-and-play manner
with existing ECU high-side outputs without requiring firmware modifications and
incorporates automotive-grade protections such as EMI filtering, ESD protection, and
surge suppression to ensure reliable operation in harsh engine bay environments.
[0058] It has thus been seen the system (100) for controlling an electronically5
controlled rotary control valve (eRCV) in a hydrogen internal combustion engine, as
described. The system (100) for controlling an electronically controlled rotary control
valve (eRCV) in a hydrogen internal combustion engine in any case could undergo
numerous modifications and variants, all of which are covered by the same innovative
concept; moreover, all of the details can be replaced by technically equivalent elements.10
In practice, the components used, as well as the numbers, shapes, and sizes of the
components can be whatever according to the technical requirements. The scope of
protection of the invention is therefore defined by the attached claims.

Claims

1. A system (100) for controlling an electronically controlled rotary control valve
(eRCV) in a hydrogen internal combustion engine, the system (100)
comprising:
a vehicle electrical power source (102) configured to provide a nominal
24 V DC supply;
an engine control unit (ECU) (104) comprising a high-side enable
output configured to selectively output an ON/OFF control signal at
approximately 24 V D, and
a frequency-based speed signal output represents an engine or rotor
speed;
a power hold relay (106) having a coil and switched contacts, the
switched contacts being connected between the vehicle electrical power source
(102) and a power input of the eRCV unit (108), wherein the RCV unit (108)
comprises a power input terminal, a ground terminal, an enable input terminal,
and a speed signal input terminal; and
eRCV enable coupling device (110) electrically coupled to the ECU
(104), the power hold relay (106) and the eRCV unit (108), wherein the eRCV
enable coupling device (110) is configured to:
receive the 24 V high-side enable signal from the ECU (104) via a pin
1,
convert the received 24V high-side enable signal into a regulated logic-
level enable signal in a range 0-5 V suitable for direct connection to the eRCV
enable input terminal (i.e. pin 3),
derive at least one regulated low-voltage supply from the 24 V vehicle
power source for the eRCV enable coupling device (110), via an integrated DC-
DC convertor,
receive a frequency-based speed signal from the ECU (104) and output
a buffered speed signal to the speed signal input terminal of the eRCV (i.e pin5
4),
provide a stable and noise- controlled ground reference between the
ECU (104) and the eRCV unit (108) via a pin 2, and
maintain energization of the power hold relay (106) and the enable
signal to the eRCV for a predefined time interval after the ECU (104) high-side10
enable output transitions to an OFF state, such that the eRCV remains powered
and enabled for controlled rotor deceleration in hydrogen combustion
operation.
2. The system (100) as claimed in claim 1, wherein the eRCV enable coupling
device (110) configured to convert the ECU (104) high-side output from
approximately 24 V DC to a logic-level enable signal not exceeding 5 V DC.
3. The system (100) as claimed in claim 1, wherein eRCV enable coupling device
(110) configured to process the frequency-based input signal in a range from 0
Hz to about 168 Hz, corresponding to an engine speed of up to approximately
1000 RPM, and to output a square-wave or conditioned signal with improved
electromagnetic interference immunity.
4. The system (100) as claimed in claim 1, wherein eRCV enable coupling device
(110) is configured to maintain energization of the power hold relay (106) for
a time period of at least five seconds after deactivation of the ECU high-side
enable output.
5. The system (100) as claimed in claim 1, wherein the predefined time interval is
programmable or configurable to accommodate different eRCV rotor inertia
characteristics and braking requirements of hydrogen internal combustion
engines.
6. The system (100) as claimed in claim 1, wherein the eRCV enable coupling
device (110) is configured to provide a controlled ground reference shared
between the ECU (104) and the eRCV unit (108) to reduce ground loop
formation and differential noise in the enable and speed signal paths.
7. The system (100) as claimed in claim 1, wherein the eRCV enable coupling
device (110) further comprises at least one protection feature selected from
electromagnetic interference filtering, electrostatic discharge protection, and
transient voltage suppression.
8. A method (300) for controlling an electronically controlled rotary control valve
(eRCV) in a hydrogen internal combustion engine, comprising:
supplying a nominal 24 V DC vehicle power to an ECU (104) and to a
power hold relay (106) connected in series with a power input of the eRCV unit
(108);15
generating, by the ECU (104), a high-side enable signal at
approximately 24 V DC corresponding to a commanded ON state of the eRCV
unit (108);
receiving the high-side enable signal at an eRCV enable coupling device
positioned electrically between the ECU (104) and the eRCV unit (108);
filtering and protecting the received high-side enable signal to suppress
electrical noise, voltage transients, and electromagnetic interference;
translating the high-side enable signal from approximately 24 V DC into
a regulated logic-level enable signal in a range of 0–5 V compatible with an
enable input of the eRCV unit (108);
supplying the translated logic-level enable signal to the enable input of
the eRCV unit (108) to permit rotary valve operation;
receiving, at the eRCV enable coupling device (110), a frequency-
based speed signal from the ECU (104) representing engine or valve rotational
speed;
buffering the frequency-based speed signal to improve signal integrity
and electromagnetic immunity;
transmitting the buffered speed signal from the eRCV enable coupling
device (110) to a speed signal input of the eRCV unit (108);
generating, within the eRCV enable coupling device (110), at least one
regulated low-voltage supply from the 24 V vehicle power using an integrated
DC-DC converter to power internal logic and signal conditioning circuits; and
upon transition of the ECU (104) high-side enable signal to an OFF
state, maintaining energization of the power hold relay (106) and the enable
signal to the eRCV unit (108) for a predefined time interval, thereby allowing
controlled deceleration of an eRCV rotor in hydrogen combustion operation.