1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 22072:2011Aerospace Electrohydrostaticactuator (EHA) Characteristics to be defined inprocurement specificationsBS ISO 22072:2011 BRITISH STANDARDNational forewordThis Brit
2、ish Standard is the UK implementation of ISO 22072:2011. Itsupersedes BS ISO 22072:2005 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee ACE/69, Aerospace hydraulic systems, fluids andcomponents.A list of organizations represented on this committee can b
3、eobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 67898 1ICS 49.080Compliance with a British Standard cannot confer immunity fromlegal obligations.This
4、 British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 August 2011.Amendments issued since publicationDate Text affectedBS ISO 22072:2011Reference numberISO 22072:2011(E)ISO 2011INTERNATIONAL STANDARD ISO22072Second edition2011-08-01Aerospace Electroh
5、ydrostatic actuator (EHA) Characteristics to be defined in procurement specifications Aronautique et espace Actionneurs lectrohydrostatiques (EHA) Caractristiques dfinir dans les spcifications dapprovisionnement BS ISO 22072:2011ISO 22072:2011(E) COPYRIGHT PROTECTED DOCUMENT ISO 2011 All rights rese
6、rved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the reques
7、ter. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2011 All rights reservedBS ISO 22072:2011ISO 22072:2011(E) ISO 2011 All rights reserved iiiContents Page Foreword iv Introd
8、uction . v 1 Scope 1 2 Normative references 1 3 Terms and definitions . 1 4 Requirements . 3 4.1 General . 3 4.2 Brief description of the system 3 4.3 Description and interfaces . 3 4.4 Performance . 4 4.5 Electrical power consumption and regeneration . 6 4.6 Hydraulic consumption . 7 4.7 Strength a
9、nd life 7 4.8 Protection against fire risk . 7 4.9 Reliability and safety . 8 4.10 Bonding 8 4.11 Lightning, electromagnetic compatibility . 8 4.12 Maintainability and servicing . 8 4.13 Thermal requirements . 9 5 Installation and operating conditions . 9 5.1 General . 9 5.2 Mechanical data . 9 5.3
10、Electrical supply data 9 5.4 Thermal data 9 5.5 Hydraulic data 10 5.6 Control and monitoring data 10 5.7 Environmental data . 10 5.8 Duty cycle data 10 Bibliography 12 BS ISO 22072:2011ISO 22072:2011(E) iv ISO 2011 All rights reservedForeword ISO (the International Organization for Standardization)
11、is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be repres
12、ented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are
13、drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International
14、 Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 22072 was prepa
15、red by Technical Committee ISO/TC 20, Aircraft and space vehicles, Subcommittee SC 10, Aerospace fluid systems and components. This second edition cancels and replaces the first edition (ISO 22072:2005), which has been technically revised. This second edition adds requirements for electronic module
16、hardware (4.3.5), operation under failure conditions (4.4.5), electrical power consumption and regeneration (4.5) and fatigue wear life (4.7.2). BS ISO 22072:2011ISO 22072:2011(E) ISO 2011 All rights reserved vIntroduction Electrohydrostatic actuators (EHAs) are integrated, electrically powered, hyd
17、raulic actuators that are used to power aircraft control surfaces or other moving parts. This International Standard provides requirements that should be included in a Procurement Specification for this type of actuator. BS ISO 22072:2011BS ISO 22072:2011INTERNATIONAL STANDARD ISO 22072:2011(E) ISO
18、2011 All rights reserved 1Aerospace Electrohydrostatic actuator (EHA) Characteristics to be defined in procurement specifications 1 Scope This International Standard defines the general characteristics, requirements and design data to be included in the procurement technical specification of an elec
19、trohydrostatic actuator (EHA) to be used to power aircraft control surfaces or other moving parts of an aerospace vehicle. This type of actuator is an alternative to the hydraulically powered servo-control actuators that are currently used. It is intended that this International Standard cover the u
20、nique requirements of EHAs. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies
21、. ISO 7137, Aircraft Environmental conditions and test procedures for airborne equipment DO-178B, Software Considerations in Airborne Systems and Equipment Certification1)DO-254, Design Assurance Guidance for Airborne Electronic Hardware1)SAE ARP1383B, Impulse Testing of Aerospace Hydraulic Actuator
22、s, Valves, Pressure Containers, and Similar Fluid System Components2)3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 electrohydrostatic actuator EHA an electrically powered actuator that includes one or several hydraulic rams NOTE 1 The chamb
23、ers of each ram are connected to an integrated hydraulic fluid reservoir and to a bidirectional, fixed-displacement pump driven by a variable-shaft-speed, bidirectional electric motor controlled by an electronic module including power electronics, mounted on the actuator or remotely, and considered
24、a part of the actuator. NOTE 2 The motor/pump/power electronics assembly may be incorporated into a standard Electrohydrostatic Module (EHM). 1) RTCA Radio Technical Commission for Aeronautics, www.rtca.org. 2) SAE Society of Automobile Engineers, www.sae.org. BS ISO 22072:2011ISO 22072:2011(E) 2 IS
25、O 2011 All rights reservedNOTE 3 A manifold, in which components necessary for additional functions can be installed, interconnects the mechanical elements; see Figure 1. The additional functions may include, for example, allowing the operation of other actuators installed in parallel, or ensuring t
26、he damping of movement of the load in case of loss of all electric power. NOTE 4 This assembly is part of the position control loop of the surface, or of any other load, in which the error signal, difference between the commanded and achieved positions determines the command of the speed and directi
27、on of rotation of the motor. Other components of the position servo-loop, e.g. position transducer, control electronics, generating the error signal and control laws, do not necessarily form part of this assembly. NOTE 5 The electronic module function may be limited to Motor Drive Electronics (MDE),
28、 higher-level functions such as closing the position loop, control laws, failure detection and isolation, and built-in-test being implemented in a central computer, or these functions can be included as an Electronics Control Unit (ECU). Key 1 command signal 7 position transducer signal 2 power supp
29、ly 8 anti-cavitation check valve (two places) 3 electronic module 9 piston 4 electric motor 10 EHM 5 reservoir 11 filling port 6 pump Figure 1 Typical arrangement of an electrohydrostatic actuator 3.2 digital signal processor DSP integrated circuit designed for processing signals by digital means as
30、 opposed to analogue means 3.3 field-programmable gate array FPGA integrated circuit designed to be configured by the designer or user after manufacturing BS ISO 22072:2011ISO 22072:2011(E) ISO 2011 All rights reserved 34 Requirements 4.1 General The requirements defined in 4.2 to 4.13 shall be met
31、under all rated operating conditions and during the service life specified. 4.2 Brief description of the system The EHA is one component of a system. The various configurations or reconfigurations typical of this system involve specific modes of EHA operation which shall be described. Normal and fai
32、lure modes of operation for the EHA shall be defined. 4.3 Description and interfaces 4.3.1 General description The unit shall be described in terms of functions and the associated terminology defined. The following are examples: control/electrical/mechanical/structural redundancy; local or remote fl
33、uid level indication/monitoring; filling, either from a ground support equipment or a central hydraulic system; draining; bleeding; internal fluid filtering; anti-back-driving device; local dissipation of generated energy; force and/or pressure and/or speed limitation; stops; temperature monitoring;
34、 heating of stand-by unit; etc. 4.3.2 Mechanical interface The specification, or a separate interface control document, shall define: allocated space envelope; dimensions and tolerances of the mechanical connections or the dimensional standards if connections are achieved through standardized compon
35、ents; line replaceable units; access once installed on aircraft; interfaces with specific items (such as hoisting devices or “jack catchers”) intended to hold the unit in place in the event of attachment rupture or disconnection, to avoid secondary damage to surrounding structures or equipment, etc.
36、, as required. BS ISO 22072:2011ISO 22072:2011(E) 4 ISO 2011 All rights reserved4.3.3 Electrical interface The specification, or a separate interface control document, shall include: wiring schematics defining the electrical connections with power supply, control and monitoring systems, standards, s
37、izes and pin allocation of interface connectors; any particular requirements or limitation on use of connectors for the line replaceable units; segregation rules to comply with, including signal separation requirements; descriptions of signals exchanged, definition of input and output impedances; po
38、wer interruption capability and definition of the strategy for longer interruptions (see 5.3); bonding interface; shielding requirements; specific insulation requirements associated with the use of high voltage d.c. 4.3.4 Hydraulic interface The hydraulic interface requirements shall include definit
39、ion and location of possible filling, bleeding, filtering and draining features. 4.3.5 Electronic module hardware, software/firmware Various control and monitoring functions, such as listed below, can be implemented locally in the embedded electronic module, which is primarily intended to host the m
40、otor drive electronics, or shared with central computers: loop closure; monitoring and redundancy management; status information; built-in test; allowable type of processor such as DSP or FPGA may be specified; etc. The level of criticality and of the associated development, verification and validat
41、ion methods, configuration control, applicable to the software and firmware shall be specified with reference to DO-178B and DO-254. Memory capacity extension and processing power shall be specified. Implementation of monitoring functions may require physical segregation, independent hardware, possi
42、ble hardware and software dissimilarity, depending on criticality. 4.4 Performance 4.4.1 General The EHA should meet the performance requirements when operating in conjunction with the other servo-loop components. BS ISO 22072:2011ISO 22072:2011(E) ISO 2011 All rights reserved 54.4.2 Mechanical perf
43、ormance The definition of the requirements for output force or mechanical power shall take into account the thermal behaviour. These mechanical requirements shall therefore be associated with their duration and environmental conditions. They shall take into account any included force, pressure or sp
44、eed limitation functions. Thus the following shall be specified. a) Maximum operating output force: the maximum driving force to be generated by the unit at very low speed (to be defined), for a short time duration (to be defined), under specified supply and environmental conditions, and the associa
45、ted tolerances. b) Maximum continuous output force: the maximum holding force, with no movement, or the maximum driving force, at very low speed (to be defined), to be generated under given supply and environmental conditions with no time limitation, with and without its possible no-back device enga
46、ged, and the associated tolerances. c) “Worst case” scenarios: operational sequences, or series of sequences, described as functions of time in terms of position, force, environmental conditions, identified as sizing cases in terms of instantaneous power absorbed or rejected, or in terms of heat gen
47、erated. Force fighting shall be considered, depending on system configuration. d) Maximum rate and associated loading conditions, or expressed as the time necessary to reach a given position under a specified load. The rate versus load characteristic shall be identified. e) Run-up time: time from ac
48、tivation of stand-by actuator to being able to achieve maximum rate with a maximum rate demand. Dynamic performance as specified below may also be a sizing consideration: working stroke, stop-to-stop stroke; possible acceptable temporary degradation of performance at start-up, following cold soak in
49、 particular; possible acoustic noise requirements; possible allowed performance degradation under extreme conditions. 4.4.3 Servo-loop static performance The following characteristics, with and without the possible anti-back-driving device, shall be specified either as the complete servo-loop requirement or as the part allocated to the actuator, taking into account data under 5.6: overall accuracy; hysteresis; resolution; stiffness; freeplay;
