1、AECMA STANDARD NORME AECMA AECMA NORM Edition approved for publication 31 July 2002 prEN 2282 Edition P 1 July 2002 Comments should be sent within six months after the date of publication to Gulledelle 94 AECMA-STAN B-1200 BRUXELLES ICs: 49.060 Will supersede EN 2282: 1992 ENGLISH VERSION Aerospace
2、series Characteristics of aircraft electrical supplies Srie arospatiale Caractristiques de lalimentation lectrique des aronefs Luft- und Raumfahrt Eigenschaften der elektrischen Stromversorgung von Luftfahrzeugen This Herospace Series“ Prestandard has been drawn up under the responsibility of AECMA-
3、STAN (The European Association of Aerospace Industries - Standardization). It is published on green paper for the needs of the European Aerospace Industry. It has been technically approved by the experts of the concerned Domain following member comments. Subsequent to the publication of this Prestan
4、dard, the technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and review by users and formal agreement of AECMA-STAN it will be submitted as a draft European Standard to CEN
5、(European Committee for Standardization) for formal vote. t Nota - Extra copies can be supplied by B.N.A.E. - Technopolis 54 - 199, rue Jean-Jacques Rousseau - 92138 ISSY-LES-MOULINEAUX CEDEX I I Electrical Domain I I I Copyright 2002 O by AECMA-STAI Page 2 prEN 2282: 2002 Contents Page O 1 2 3 4 4.
6、1 4.2 5 5.1 5.2 5.3 5.4 5.5 6 6.1 6.2 6.3 Introduction . . Scope . Normative references Definitions . Requirements common to all electrical power systems . General requirements for electrical power generation . General requirements for utilization equipment A.C. power system . General . Supply chara
7、cteristics for category A (CF) system . Supply characteristics for category A (NF) system . Supply characteristics for category A (WF) system Requirements relating to utilization equipment . D.C. power system 28 V . General . Requirements relating to utilization equipment . Supply characteristics fo
8、r 28 V systems . 3 3 3 3 6 6 7 7 7 8 9 10 11 13 13 13 13 Page 3 prEN 2282: 2002 O Introduction This standard has taken into consideration national documents together with IS0 1540 and STANAG 3456. 1 Scope This standard specifies the characteristics of electrical power supplied to the terminals of eq
9、uipment installed in the aircraft. It also defines the supply system and compatibility requirements for equipment together with the special systems with constant and variable frequency. This standard applies to a.c. and d.c. on-board or ground systems. 2 Normative references This European Standard i
10、ncorporates by dated or undated reference provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this E
11、uropean Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. IS0 1540 Aerospace - Characteristics of aircraft electrical systems EN 3830 Aerospace series - Electrical load and power source analysis 1) STANAG
12、 3456 Aircraft Electrical Power System Characteristic 3 Definit ions For the purpose of this standard the following definitions apply: 3.1 abnormal operation the consequence of a failure or disturbance bringing about the loss or deterioration of the system characteristics which may then reach the li
13、mits provided by the protective devices The extent and duration of this abnormal operation may escape detection until the end of the flight. 3.2 available power of a system The power which can be used simultaneously under continuous steady-state conditions taking account of the specified conditions
14、of use in the aircraft and the rated power of each power supply 1) Published as AECMA Prectandard at the date of publication of this standard Page 4 prEN 2282: 2002 3.3 categories category A( ): this category refers to aircraft electrical networks where the primary power is from a constant or variab
15、le frequency a.c. system, and where the d.c. system is supplied from transformer-rectifier units A battery may be floating on the d.c. bus. A(CF) designates a.c. or/and d.c. electrical network where the primary power is from constant frequency (400 Hz) a.c. input power A(NF) designates a.c. or/and d
16、.c. electrical network where the primary power is from narrow range variable frequency (360 Hz to 650 Hz) a.c. input power A(WF) designates a.c. or/and d.c. electrical network where the primary power is from wide range variable frequency (360 Hz to 800 Hz) a.c. input power category B: this category
17、refers to aircraft d.c. electrical networks which are supplied by engine-driven alternator/rectifiers, or d.c. generators where a battery of significant capacity is floating on the d.c. bus at all times category Z: this category refers all other d.c. types of electrical networks applicable to these
18、standards. This category shall be acceptable for use in place of category A( ). Examples of this category are d.c. networks supplied from variable-speed generators where: a) b) c) the d.c. power supply does not have a battery floating on the d.c. bus, or control or protective equipment may disconnec
19、t the battery from the d.c. bus, or the battery capacity is small compared with the capacity of the d.c. generators. 3.4 crest factor the ratio of the peak to r.m.s value of an a.c. waveform measured under steady state conditions 3.5 drift this is a random and extremely slow variation in a controlle
20、d parameter inside the specified limits The speed of variation or drift rate of the parameter is expressed in Hz/min or in V/min. 3.6 electrical network an assembly constitued by the sources of electrical power, utilization equipment, safety device, and all common connections of the installation 3.7
21、 emergency operation the condition of the electrical system when the main power supplies are unable to provide sufficient or proper electrical power 3.8 frequency modulation the cyclic (generally non-sinusoidal) and/or random variation of the frequency around a mean value during a one minute period
22、in steady state conditions Page 5 prEN 2282: 2002 3.9 individual harmonic distortion Di Hi Di% = 100 x - H1 where: H1 = r.m.s value of fundamental current or voltage Hi = r.m.s value of ith harmonic current or voltage This is the ratio between the r.m.s value of the ith harmonic and the r.m.s value
23、of the fundamental component. The harmonic analysis or spectrum of distortion decomposes a periodic wave giving the amplitude of its components depending upon their frequency. 3.1 O modulations the modulation of the parameter is the cyclic (generally non-sinusoidal) and/or random variation of its ma
24、ximum value around a mean value in steady-state conditions For a.c. power, the maximum value of modulation (of voltage or current) is the maximum difference (peak to valley) between the peak values of the parameter measured on the most unfavourable phase and polarity. For d.c. power, it is called “r
25、ipple“, measured as the peak to peak excursion about the mean value. in both cases, modulation may be likened to the superimposition of an alternating wave on the base parameter. A spectral analysis of this wave or of its resulting envelope indicates the frequencies and amplitudes of its components,
26、 with a view to limiting them (see figures 8 and 9). 3.1 1 normal operation this is the situation where all the intended operational modes of the aircraft electrical power system are available 3.12 phase displacement the angular separation between any 2 phase voltages of a 3 phase network 3.13 phase
27、 voltage unbalance the difference between the maximum r.m.s phase voltage and the minimum r.m.s phase voltage 3.14 power factor for a.c. utilization equipment, power factor is the ratio of the real or active power (in Watts) to the apparent power (in Volt-Amperes) 3.15 spikes brief voltage variation
28、s, compared with steady-state conditions, which arise in the distribution system, due for example, to switching of inductive loads that are superimposed on the aircraft power supply They generally produce a voltage peak and/or a wave train, the characteristics of which are dependent on relative impe
29、dances of the line, equipment and power supply, and on the manner in which the interruption occurs. Page 6 prEN 2282: 2002 3.16 steady-state conditions operating conditions of the system when only negligible changes in electrical parameters appear which are not due to any variation in load or any fa
30、ult 3.1 7 total harmonic distortion Dt (current or voltage) where: H1 = rm.s value of fundamental current or voltage H, = r.m.s value of nth harmonic current or voltage This is ratio of the r.m.s value of the supply waveform less the fundamental component, to the r.m.s value of the fundamental perio
31、dic wave. 3.18 transients momentary variations of a characteristic from its steady-state conditions. They result, for example, from the response of the generator regulator to a disturbance Brief undervoltages or interruptions due to switching, may be considered as transients. 3.19 utilization equipm
32、ent any equipment or any functional group of units consuming electrical energy 3.20 voltage values the value of the a.c. voltage is defined by the r.m.s. value measured between each phase and the neutral, the value of the d.c. voltage is defined by the mean arithmetical value measured between the po
33、sitive terminal and earth 4 Requirements common to all electrical power systems 4.1 4.1.1 Design and control Design and control of the electrical power sources shall ensure that the power supply characteristics of this standard are available at the terminals of the utilization equipment. Except wher
34、e specified otherwise (e.g. nominal voltages), all the values of parameters specified in this standard shall be measured at the equipment terminals including during the power supply to the aircraft by a ground support unit, in conformity with this standard. General requirements for electrical power
35、generation 4.1.2 Supplied power The supplied power shall satisfy the power requirement of the connected loads under all aircraft operating conditions. This applies for both a.c. and d.c. power supply systems and shall be verified by means of an electrical load and power source analysis as defined in
36、 EN 3830. Page 7 prEN 2282: 2002 4.1.3 Interruptions The duration of normal power interruptions caused by busbar or power source switching shall not exceed 50 ms except where specified otherwise, in which case they shall not exceed 200 ms. During this time the voltage may be between zero and the app
37、licable steady state limits specified in this standard. 4.2 4.2.1 General The utilization equipment shall provide the full performance required by its specification when supplied with electrical power having the characteristics for normal operation as laid down in this standard. General requirements
38、 for utilization equipment 4.2.2 Supply type Single phase supplied equipment should be connected between phase and neutral. All equipment for which power consumption exceeds 500 VA should be supplied from a 3 phase power source. These requirements may be disregarded where: a) b) emergency operation
39、is required c) 28 V d.c. is the only supply available interrupt free supplies are required (unless no break power transfer is available on the a.c. supply bus). Utilization equipment shall preferably use only one type of (a.c or d.c.) power. If not the equipment shall give its specified performance
40、when subjected to simultaneous variations of both power inputs within the limits shown in the relevant tables of this standard. The degree of performance degradation allowed during abnormal and emergency operation of the electrical system shall be stated in the individual specification of the utiliz
41、ation equipment. The equipment shall not produce any unsafe condition during these system operations. Utilization equipment characteristic such as pulsed load, d.c. rectification feedback or inrush current shall not cause the supply characteristics to exceed the limits shown in the relevant figures
42、of this standard. 4.2.3 Supply interruptions The utilization equipment shall withstand power supply interruptions as specified in 4.1.3 without damage and recover to full performance when the system is restored. Equipment performance during these events shall be as defined in the equipment specifica
43、tion. 5 A.C. power system 5.1 General The following paragraphs give the characteristics of 3 phase 1 151200 V systems. For alternative voltages the limits follow those hereafter except voltage values are 26/115 times of those shown for 26 V a.c. systems and 23011 15 times for 230 V a.c. systems. Pag
44、e 8 prEN 2282: 2002 Power factor 5.2 5.2.1 Normal Abnormal 0,75 Lag to 0,95 Lead Supply characteristics for category A (CF) system Limits 3-Phase average (V r.m.s) Individual phases (V r.m.s) Table 1 - Summary of category A(CF) system supply characteristics 105,5 to 1203 104 to 122 98,5 to 132,5 97
45、to 134 System limits I Phase unbalance (V r.m.s) 6 DC Component (V d.c.) - 0,l to 0,l - 0,2 to 0,2 I Phase displacement (Degrees) I 116 to 124 I Amplitude (V) 395 Frequency components Figure 8 Crest factor Total harmonic distortion (%) 1,31 to 1,51 1,31 to 1,51 8 10 individual harmonic distortion (%
46、) Frequency (Hz) 6 8 395 to 405 370 to 430 I Spikes I Figure 10 I Figure 10 Frequency modulation NOTE circuit breaker operating time. A short circuit may result in supply voltage and frequency remaining at or close to zero during the All parameters above are measured at the input terminals of the ut
47、ilization equipment. The voltage drop between the equipment terminals and the point of regulation will be 4 V maximum. Emergency supply limits shall be defined for each aircraft by the manufacturer. Figure 2 Voltage transients Frequency transients Figure 6a Figure 3a Figure 6c - See note. Figure 3b
48、- See note. Page 9 prEN 2282: 2002 Power factor 5.3 5.3.1 Limits Supply characteristics for category A (NF) system System limits Normal Abnormal 0,75 Lag to 0,95 Lead Table 2 - Summary of category A(NF) system supply characteristics Individual phases (V r.m.s) Phase unbalance (V r.m.s) 104 to 122 6
49、97 to 134 98,5 to 1323 I 3-Phase average (V r.m.s) I 105,5 to 1203 I 7 Phase displacement (Degrees) 116 to 124 -0,l to 0,l DC Component (V d.c.) - 0,2 to 0,2 Modulation Amplitude (V) Frequency components 3.5 Figure 8 Crest factor 1,31 to 1,51 1,31 to 1,51 Total harmonic distortion (%) Individual harmonic distortion (%) 8 10 6 8 Frequency (Hz) Max rate of frequency change NOTE 1 A short circuit may result in supply voltage and frequency remaining at or close to zero during the circuit breaker operating time. NOTE 2 For aircraft with two or more engines the manufacturer shall id
