[21空调] 733增压系统学习

PRESSURIZATION CONTROL SYSTEM - DESCRIPTION AND OPERATION

1. General

A. The pressurization control system is an electrically operated and electronically controlled system,

which meters the exhaust of ventilating air to supply controlled pressurization of the passenger and

control cabins, the electronic compartment, the two cargo compartments, and the lower nose compartment. The pressurization control system has a pressure control panel, a pressure controller,and a cabin pressurization outflow valve (Figure 1 ). The pressurization control system characteristics are as follows:

增压系统是一个电操作和电控制系统，它计量流通空气的排出，控制客舱、驾驶舱、电子舱、两个货舱和前下舱的压力。增压控制系统有一个增压控制面板、一个压力控制器和一个增压后溢流活门，该增压系统特性如下：

(1) The system has four operating modes; automatic, standby, ac manual and dc manual. Automatic is the normal operating mode. Standby is a semiautomatic backup. The ac manual and dc manual modes are backups for automatic and standby modes. Normal operation is automatic and normally requires no adjustment by the flight crew throughout the flight except for barometric correction.

    该系统有4个工作模式：自动、备用、人工AC和人工DC。自动是一个正常工作模式，备用是一个半自动备份，人工AC和人工DC模式是自动和备用模式的备份，除了气压修正外整个飞行阶段是正常自动工作，并且无需机组调节。

(2) The ac manual mode and the dc manual mode supply direct control to the outflow valve through separate electrical actuators. The manual modes back up the automatic and standby systems.

    人工AC和人工DC模式是通过各自的电马达直接控制后溢流活门，该人工模式是自动和备用系统的备份。

(3) In the automatic mode, the system accepts manual inputs of planned flight altitude and landing altitude before takeoff. It then finds the lowest possible cabin pressure that can be maintained during airplane high altitude flight and schedules any necessary change in cabin pressure during the flight without any action by the crew. The system can also be reset if a change in planned flight altitude or landing field altitude is made.

    在自动模式中，起飞前系统接收计划飞行高度和着陆高度的人工输入，此时能找到在高高度飞行时被保持最低可能的座舱压力和在没有机组操作的飞行期间计划任一所需的座舱压力变化。假如计划飞行高度和着陆机场高度有了改变，该系统也能被重新设定。

(4) Cabin pressure rate of change is automatically controlled in AUTO. Rate of change may be manually controlled in STBY.

    在自动方式座舱压力变化率是自动控制的，备用方式的变化率是可以人工控制的。

(5) Barometric correction for automatic and standby pressure control assures that cabin pressure and landing field pressure are approximately the same at landing.

    自动和备用压力控制的气压修正可以确保座舱压力和着陆机场压力在着陆时基本相等。

(6) A mode selector switch on the control panel permits selection of four modes of operation plus a check position for system test.

    控制面板的模式选择电门允许选择4个工作模式和一个作为系统测试的检查位。

(7) The STANDBY system automatically takes over to control cabin pressure according to cabin altitude and rate of cabin pressure change settings if certain limits are exceeded in AUTO. In addition, a manual transfer can be made from AUTO to STBY, if desired, by use of the mode selector switch.

    如果在自动方式某一确定限制被超出，根据座舱高度和座舱压力变化率的设置，备用系统自动接管控制座舱压力，另外也能通过使用模式旋转电门，人工转换从自动到人工。

B. Operation of the pressurization control system requires signals into the pressurization control system from direct ambient pressure sensing, barometric pressure correction and the landing gear ground safety sensor (LANDING GEAR SAFETY SENSORS - DESCRIPTION AND OPERATION, PAGEBLOCK 32-09-00/001) for the automatic mode and from the air data computer (AIR DATA SYSTEMS - DESCRIPTION AND OPERATION, PAGEBLOCK 34-12-01/001 or AIR DATA SYSTEMS - DESCRIPTION AND OPERATION, PAGEBLOCK 34-12-00/001 ), barometric correction and the landing gear ground safety sensor in the standby mode. Electrical circuit protection for the pressurization control system is supplied by circuit breakers on the P6 circuit breaker panel.

  增压控制系统工作要求信号进入增压控制系统，自动方式需要直接外界压力感受、气压修正和起落架地面安全传感器，备用方式从大气数据计算机、气压修正和起落架地面安全传感器得到信号，P6板跳开关板的跳开关提供增压控制系统线路保护。

2. Pressure Control Panel压力控制面板

A. The pressure control panel includes four groupings of dials, switches, and indicators used in the operation of the pressurization control system. One grouping is for the automatic (AUTO) mode of operation, another is for the semiautomatic or standby mode, the third is for the manual mode, and the fourth is to let you choose the desired mode of control and function available.

   压力控制板包括了用于增压控制系统操作的4组盘面、电门和一个指示表，一组作为自动工作方式，另一组作为半自动或备用方式，第三组是人工方式，第四组是由你选择所需的控制方式和可利用的功能。

B. For the AUTO mode there is an adjusting knob and indicator (LAND ALT) for setting destination landing field altitude and another knob and indicator (FLT ALT) for setting cruise altitude.

   自动方式有一个调节旋钮和指示器用于着陆目的地场高设置，另一个旋钮和一个指示用于巡航高度的设置。

C. Instruments for STANDBY consist of a cabin altitude adjusting knob (CAB ALT) and indicator and a cabin rate of pressure change (CAB RATE) knob. There is an index mark on the panel for the CAB RATE knob which marks the setting for approximately 300 feet per minute rate of change. CAB RATE range is from 50 to 2000 sea level ft/ min.

   备用方式的仪表包括座舱高度调节旋钮、指示器和一个座舱压力变化率旋钮。在变化率旋钮处的一个指示标志用于设置接近300英尺/分钟变化率，变化范围从50-2000海平面FEET/MIN。

D. The manual mode uses a three-position self-centering toggle switch to control the position of the outflow valve. The switch has momentary contacts to drive the outflow valve open or closed. Releasing the switch opens the contacts, stopping outflow valve movement. A position indicator is supplied for monitoring outflow valve position in all modes.

   人工模式用一个三位自定中波动开关去控制后溢流活门，电门有一个瞬间接触去驱动后溢流活门开/关，释放电门断开接触，停止后溢流活门移动，一个位置指示表提供活门所有方式的位置指示。

E. The fourth section of the panel includes a five-position mode selector switch, CHECK, AUTO, STBY, AC and DC MAN; and a two-position FLT-GRD toggle switch. The FLT-GRD switch is used in conjunction with the mode selector switch and landing gear sensor switch to control minimum cabin pressurization on the ground when the mode selector is in AUTO or STBY, and to check the rate limit fault detector of the auto transfer when the mode selector is in the CHECK position. When the mode selector is in MAN AC or DC position, cabin pressurization is controlled directly by the use of the manual OPEN-CLOSE switch to actuate the outflow valve under ac or dc control, depending on the position of the selector switch.

   面板的第四个部分包含了一个5位置模式选择电门、检查、自动、备用、AC/DC人工和一个两位置FLT-GRD拨动电门。当选择AUTO或STBY时，FLT-GRD电门用于与模式选择电门和起落架传感器联合控制地面最低座舱压力；并且当选择在CHECK位时，去检查自动转换的变化率限制失效探测器；当选择MAN AC或DC位，依据选择电门位置，座舱压力通过使用人工OPEN-CLOSE电门直接控制作动后溢流活门。

3. Pressure Controller 压力控制器

A. The pressure controller is an electronic unit which receives inputs from the pressurization control panel, airplane ambient pressure and cabin pressure, then positions the outflow valve to maintain proper differential pressure (Figure 2).

   压力控制器是一个电子装置，接收增压控制面板、飞机外界压力、座舱压力和后溢流活门的输入，以维持正压差。

B. Two completely independent pressure control system networks are contained within the pressure controller. The automatic system operates as a function of destination landing field altitude and cruise altitude while the standby system operates according to the selected cabin altitude and selected rate of cabin pressure change.

   压力控制器里包含两套完全独立的压力控制系统网，当备用系统工作时，根据所选择舱高度和座舱压力变化率，自动系统操作作为目的地场高和巡航高度的函数。

C. Inputs to the pressure controller for the automatic and standby systems are shown schematically on

a block diagram (Figure 2 ).

作为自动和备用系统，给压力控制器的输入看方块示意图（图2）

D. All outputs from the pressure controller operate the cabin pressurization outflow valve. The controller will operate either under the automatic system or the standby system, but never the two systems simultaneously. The FLT-GRD switch is used to modify the two outputs for cabin pressurization control on the ground. When the switch is moved to FLT position with the mode selector in AUTO the valve will move to a position which will cause cabin pressure to rise slightly above (approximately 0.1 psi) that of the takeoff field. With the selector in STBY the valve will be positioned to control the pressure to the selected standby cabin altitude. With mode selector switch in either AUTO or STBY and FLT-GRD switch is moved to GRD (airplane on ground), the outflow valve will move to the full open position at the rate necessary to completely depressurize the airplane at rate limit.

  压力控制器所有的输出操作座舱增压后溢流活门，控制器可操作任一自动系统或备用系统、但不会两个系统同时工作。FLT-GRD电门用于地面修正座舱压力控制器的两个输出，当电门移动到FLT位，且模式选择在AUTO，活门将自动移动到一个位置，并引起座舱压力微微上升到起飞机场场压以上（约0.1PSI）。选择STBY位，活门将被定位去控制所选择备用座舱高度时的压力。方式选择电门在任一AUTO或STBY和FLT-GRD电门移动到GRD位，后溢流活门将以一定的速率移动到全开位，以一定速率限制完全释压飞机。

E. On the front of the controller, there are test points under a cover which are used for trouble-shooting the pressurization control system. On the rear of the controller, the upper connection is used only for bench test.

  在控制器前面的盖板下面有用于增压控制系统故障检测的测试点，控制器后面上接口仅用于台架测试。

F. The pressure controller is installed in the electronic equipment compartment on the forward top shelf. There is a delta P module installed adjacent to the pressure controller, which supplies a maximum of 7.45 psi with the pressurization mode selector in AUTO and 28,000 ft or below selected with the FLT ALT selector. A 7.80 P is supplied when FLT ALT above 28,000 ft is selected with the pressurization mode selector in AUTO. STANDBY maximum pressure differential is 7.8 psi.

   压力控制器安装在E/E舱前支架上，有一个压差组件位于控制器附近，当增压模式选择自动和28000feet或已选定飞行高度时提供最大7.45PSI压差。

4. Cabin Pressurization Outflow Valve 座舱增压后溢流活门

A. The outflow valve is a thrust recovery, rotating gate valve which is driven by either a rotary dc electrical actuator or a rotary ac electrical actuator. Each actuator connects to the gate shaft with an electrically operated spring-loaded clutch. AUTO and AC MANUAL modes operate the ac actuator. STANDBY and DC MANUAL modes operate the dc actuator. When either actuator is in operation the clutch to the other actuator is disengaged.

  后溢流活门是一个可反向推动的旋转门活门，由任一旋转AC或DC电作动器驱动，每个作动器连接到装有电操作弹簧载荷离合器的门轴上，当任一作动器操控该离合器去脱开另一作动器时，AUTO和AC MANUA模式操控AC作动器，STANDBY和DC MANUAL模式操控DC作动器。

B. With no electrical power to the clutches, the dc actuator clutch is spring loaded disengaged and the ac actuator clutch is spring loaded engaged. The clutches are energized when operating from the standby system or the manual dc system. With electrical power to the clutches, the dc actuator clutch is engaged and the ac actuator clutch is disengaged.

  离合器无电源时，DC作动器离合器是靠弹簧载荷脱开，并AC作动器离合器是靠弹簧载荷接通。当操控备用系统或人工DC系统时，作为离合器有电源，DC作动器离合器是接通的，AC作动器离合器是脱开的。

C. There is a limit switch installed on each end of the valve gate shaft. The switches assure that the forward outflow valve (CARGO COMPARTMENT HEATING - DESCRIPTION AND OPERATION, PAGEBLOCK 21-43-00/001) does not affect the cabin pressurization control system. The forward outflow valve closes when the cabin pressurization outflow valve is within 0.5 degrees of the full closed position. The forward outflow valve opens when the cabin pressurization outflow valve opens approximately 4.5 degrees.

  在每个活门门轴末端安装有一个限制电门，该电门确保前溢流活门不会影响座舱增压控制系统。当座舱增压后溢流活门位于全关闭位置0.5°范围内时，前溢流活门关闭；当座舱增压后溢流活门位于打开接近4.5°时，前溢流活门打开。

WARNING: OUTFLOW VALVE IS MOTOR-OPERATED. DO NOT INSERT HAND OR TOOLS IN OUTLET DURING ANY GROUND OPERATION OR INJURY TO PERSONS CAN OCCUR.

警告：后溢流活门是马达操作的，在任一地面操作时不要插入手和工具在出口处，以免伤及人员。

D. The outflow valve is installed so its outlet is flush with the body skin. The valve is found to the right of the airplane centerline, at the underside of the airplane, approximately below the aft right service door.

   后溢流活门出口与机身蒙皮平齐，该活门位于飞机下腹中轴线右侧，靠近后勤务门下边。

5. Forward Outflow Valve 前溢流活门

A. The forward outflow valve is located at the forward left side of the forward cargo compartment. The forward outflow valve is a component of the cargo heating system (CARGO COMPARTMENT HEATING - DESCRIPTION AND OPERATION, PAGEBLOCK 21-43-00/001) and does not affect the cabin pressurization control system. This is assured by an electrical circuit that closes the forward outflow valve whenever the cabin pressurization outflow valve is nearly closed. There is a limit switch installed in each actuator of the cabin pressurization outflow valve. The forward outflow valve will close when the cabin pressurization outflow valve is within 0.5 degrees of closed and will open when the pressurization outflow valve opens approximately 4.5 degrees. An electrical circuit also closes the forward outflow valve any time the cabin air recirculation fan is operating (Figure 3).

   前溢流活门位于前货舱前左侧，它是货舱加温系统的部件，且不影响座舱增压系统，只要座舱增压后溢流活门接近关闭，那么前溢流活门通过电子线路确保被关闭。有一个限制电门安装在每一个座舱增压后溢流活门的作动器上，当后溢流活门在关闭位0.5°时前溢流活门关闭；当后溢流活门打开接近4.5°时前溢流活门打开。当座舱空气再循环风扇在任何时间工作时，有一个电子线路也能关闭前溢流活门。

6. Operation 操作

A. The automatic mode is the normal operation of the pressurization control system. The destination landing field altitude and desired cruise altitude are set on the control panel, converted to voltage signals and input to the cabin pressure controller. The controller also receives signals from the air data computer, barometric correction potentiometer, outflow valve position feedback, and from the landing gear ground safety sensor. The controller also senses cabin and ambient air pressure and converts these to voltage signals. The controller provides voltage signals to the outflow valve causing the valve to modulate the flow of cabin air to maintain cabin pressure at the desired level.

   增压控制系统正常工作是自动模式，在控制面板上设置目标着陆机场高度和所需巡航高度，转换成电压信号并输入给CPC；CPC也从ADC、修正场压表、后溢流活门位置反馈和起落架地面安全传感器接收信号；CPC也感受座舱和外界空气压力，并转换成电压信号。CPC提供电压信号给后溢流活门，引起活门去调节座舱空气流量，以便维持座舱压力到所需值。

B. Pressurization control is automatically transferred from automatic mode to standby if the cabin pressure rate of change exceeds 1.0 psi per minute or cabin altitude exceeds 13,895 feet. In the event of a power failure to the automatic system, control will automatically be transferred to the standby system provided power is available to that system. Upon transfer, the cabin pressure will change to the selected standby cabin altitude at the selected standby rate of change. During standby control the cabin altitude is limited to 14,625 feet by a pressure switch in the controller. This signals the dc actuator, which modulates the outflow valve closed. The AUTO FAIL and STANDBY lights come on when the automatic system has been transferred to the standby system and the mode selector is in AUTO. The automatic mode of operation may be reselected after an automatic transfer to standby. If any fault remains in the automatic mode, the system will automatically transfer back to the standby mode.

   如果座舱压力变化率改变超过1.0psi/min或座舱高度超过13895英尺，增压控制就自动从自动模式转换到备用模式。自动系统发生电源失效时，将自动地转换到备用系统电源，在转换器上面，座舱压力将改变到以所选择备用爬升率的所选备用座舱高度。在备用控制期间，座舱高度通过控制器的一个压力电门被限制到14625英尺，这就给信号到DC作动器，调节后溢流活门关闭。当自动系统转换到备用系统，且方式选择在AUTO时，AUTO FAIL和STANDBY灯就亮，自动转换到备用之后可以再次选择自动系统工作，假如自动模式的任一失效，该系统将自动返回到备用模式。

C. The standby system may be utilized, although the automatic change to standby has not occurred. By moving the selector switch to STBY after setting the cabin altitude and pressure rate of change, the standby system will control cabin pressure. The STANDBY light will come on. The possible indicator light conditions for the standby mode are:

   尽管自动改变到备用不会方式，但备用系统仍然可以使用，在设置座舱高度和压力变化率之后，通过移动选择电门到STBY，该备用系统将控制座舱压力，STANDBY灯将亮，作为备用模式可能的指示灯状态如下：

(1) When standby mode is selected, only the STANDBY light will be on.

    当备用模式被选择时，仅有STANDBY灯亮。

(2) When an automatic transfer to standby has taken place and the selected mode is still AUTO the STANDBY and AUTO FAIL lights will be on. The AUTO FAIL light will go out when standby is manually selected.

    当发生自动转换到备用，且方式选择在AUTO，STANDBY和AUTO FAIL灯会亮；当人工选择到备用，AUTO FAIL灯会灭。

(3) If an automatic fault occurs and the standby mode is inoperative, only the AUTO FAIL light will be on.假如发生自动失效，且备用模式不工作，仅有AUTO FAIL灯亮。

D. Manual operation of the outflow valve occurs when the mode selector switch is moved to either MAN AC or MAN DC. Electrical power is switched to the manual control outflow valve toggle switch and the valve can be opened or closed as desired. A single toggle will change the valve position and cause a cabin pressure change in flight. When the switch is released the valve will hold the position obtained. During manual control the cabin altimeter, rate of climb, and differential pressure indicators must be monitored for obtaining the desired cabin condition. The MANUAL light above the control panel comes on during manual control.

当方式选择电门移动任一MAN AC或MAN DC时，人工将操纵后溢流活门。电源被转换到人工控制后溢流活门拨动开关，并根据需要去打开或关闭活门，一个单个拨动将改变活门位置并引起空中座舱压力改变，当释放该电门，活门将保持在所获得的位置。人工控制座舱高度期间，爬升率和压差指示表必须要监控，以便获得所需座舱状态，人工控制期间，控制面板上面的MANUAL灯会亮。

E. The FLT-GRD switch is used to control cabin pressurization during takeoff and after landing in order to minimize the pressure fluctuations as the controller transfers from the ground to flight modes of operation. When the controller is functioning in AUTO and the FLT-GRD switch is placed in the FLT position, the minimum differential pressure control circuit will provide a signal the outflow valve to close to pressurize the cabin to approximately 0.1 psi above ambient (altitude approximately 200 sea level feet below field elevation). When the controller is operated in STBY mode, the cabin altitude selector must be set to provide a cabin altitude 200 feet below the takeoff or landing field elevation. When the FLT/GRD switch is placed to FLT the pressurization controller will provide a signal to close the outflow valve and pressurize the airplane to 200 feet below the selected field elevation under rate limit control. After landing when FLT-GRD switch is moved to GRD, the outflow valve will move to the full open position at the rate required to completely depressurize the airplane under rate limit control.

   FLT-GRD电门用于起飞期间控制座舱增压，着陆后随着控制器转换地面到空中工作模式，以便减小压力波动。当控制器运行在AUTO，且FLT-GRD电门在FLT位，最小压差控制电路提供信号给后溢流活门去关闭，增压座舱到大约外界气压以上0.1psi(低于海平面大约200英尺)。当控制器工作在STBY模式，座舱高度选择器必须设置提供起飞或着陆机场以下200英尺的座舱高度，当FLT/GRD电门放置在FLT，增压控制器将提供一个信号区关闭后溢流活门，并在一定的速率限制控制下，增压飞机到所选择场高以下200英尺。着陆之后当FLT-GRD电门移动到GRD，后溢流活门将以一定速率要求移动到全开位，在一定速率限制下完全释压飞机。

F. The characteristics of the pressurization control system in the event of a power loss and restoration

are as follows:电源丢失时增压控制系统的特性，根据下面恢复：Table 1/21-31-00-993-803-001

*[2] System automatically transfers to standby