lesson-29-CONTROL-SYSTEMS-轮机英语课件

1、LESSON 29 CONTROL SYSTEMS (DIESEL ENGINE BRIDGE CONTROL SYSTEM) II Jimei universityLESSON 29 CONTROL SYSTEMS JimeFig. 9 shows the basic requirements for starting and control of a direct reversing slow speed diesel engine. Jimei universityFig. 9 shows the basic requireThe basic control loop for diese

2、l engine is of closed loop form with a two or, three-term controller, possibly with a load limiting device and alarm, controlling the engine speed. Jimei universityThe basic control loop for dielesson-29-CONTROL-SYSTEMS-轮机英语课件lesson-29-CONTROL-SYSTEMS-轮机英语课件This error signal is then used by the cont

3、roller to adjust the fuel racks to return the engine speed to that required. Jimei universityThis error signal is then usedElectronic, electro-pneumatic, electro-hydraulic and pneumatic systems may be used for signal transmission and fuel rack operation. Jimei universityElectronic, electro-pneumatic

4、,The direction of rotation required is achieved by moving a lever in a horizontal slot, Jimei universityThe direction of rotation requmovement to either extreme operating the valves controlling the servo-motor which positions the cam shaft for the correct air start and fuel valve timing for the requ

5、ired direction of rotation. Jimei universitymovement to either extreme opeThe lever is then moved in a vertical slot, the initial movement actuating(操纵、驱动) the starting sequence on air andJimei universityThe lever is then moved in a vand when a pre-set rpm has been reached (30 r/min for example) the

6、 air is tripped(切断) and fuel applied.Jimei universityand when a pre-set rpm has beeSubsequent(后续的) movement of the lever operates a servo-mechanism which adjusts the speed setting lever on the engine and which is in turn connected to the governor. Jimei universitySubsequent(后续的) movement of thThe st

7、arting sequence is monitored by the interlock and check circuits shown, and a programmer(程序控制器). Jimei universityThe starting sequence is monitThis allows the maximum acceleration to commensurate with(与相应) safe operational requirements of the engine whilst manoeuvring but prevents engine overloading

8、. Jimei universityThis allows the maximum acceleIt also programmes the increase in power when moving from Full Ahead to Full Away, guarding against excessive power demands and propeller cavitation(空洞、气蚀) and critical speed slipping. Jimei universityIt also programmes the increasFor crash manoeuvres(

9、应急操作) the lever is moved from one extreme to the other, the sequence of events is then controlled to braking, starting and reaching full speed (ahead or astern). Jimei universityFor crash manoeuvres(应急操作) theDelays may be fitted to prevent braking air being applied until the engine speed has dropped

10、 to a pre-determined r/min to prevent excessive use of starting air and cavitation. Jimei universityDelays may be fitted to prevenAn alarm may be fitted to warn if starting air is applied to the engine for longer than, for example, 15 seconds. Crash manoeuvre signals may cut-out the governor. Jimei

11、universityAn alarm may be fitted to warnBridge/Engine room control transfer may be carried out by the bridge-engine room telegraph(传令钟) with a special bridge control segment(控制部分). Jimei universityBridge/Engine room control traWhen both bridge and engine room pointers are on this segment, the bridge

12、 has control of the engine, Jimei universityWhen both bridge and engine robut if the pointer on either telegraph is moved from this position, the engine room has control, and manoeuvring may be carried out using the engine room/bridge telegraph. Jimei universitybut if the pointer on either tLocal ma

13、nual control facilities also must be provided. Jimei universityLocal manual control facilitieBridge instrumentation will vary according to the desires of the ship owner and manufacturer, Jimei universityBridge instrumentation will vabut is required to include rpm indicator, direction of rotation ind

14、icator and starting air pressure, Jimei universitybut is required to include rpmwhilst for unattended machinery space vessels, an emergency stop control system independent of the bridge control system is required. Jimei universitywhilst for unattended machinerAlso the bridge watchkeeper must be made

15、 aware of any machinery fault, that the fault is being attended to and that it has been rectified. Jimei universityAlso the bridge watchkeeper muThere should be two means of communication between the bridge and main control station in the machinery space, one to be independent of the main electrical

16、 power supply. Jimei universityThere should be two means of cIn some cases facilities may be provided for emergency overriding oil pressure shutdown. Jimei universityIn some cases facilities may bIf this facility is used, adequate warning must be given to the engine room staff. Jimei universityIf th

17、is facility is used, adeqREADING MATERIAL A. CONTROL OF PROPULSION MACHINERY FROM THE NAVIGATING (航行、驾驶) BRIDGE Jimei universityREADING MATERIAL A. CONTROL OF1. Under all sailing conditions, including manoeuvring, the speed, direction of thrust and, if applicable, Jimei university1. Under all sailin

18、g conditionthe pitch of the propeller shall be fully controllable from the navigating bridge.Jimei universitythe pitch of the propeller shaa) Such remote control shall be performed by a single control device for each independent propeller, Jimei universitya) Such remote control shall bwith automatic

19、 performance of all associated services, including, where necessary, means of preventing overload of the propulsion machinery.Jimei universitywith automatic performance of b) The main propulsion machinery shall be provided with an emergency stopping device on the navigating bridge which shall be ind

20、ependent of the navigating bridge control system. Jimei universityb) The main propulsion machine2. Propulsion machinery order from the navigating bridge shall be indicated in the main machinery control room or at the propulsion machinery control position. Jimei university2. Propulsion machinery orde

21、r 3. Remote control of the propulsion machinery shall be possible only from one locating at a time. Jimei university3. Remote control of the propuThe transfer of control between the navigating bridge and machinery spaces shall be possible only in the main machinery space or in the main machinery con

22、trol room.Jimei universityThe transfer of control betweeThe system shall include means to prevent the propelling thrust from altering significantly when transferring control from one location to another. Jimei universityThe system shall include means4. It shall be possible for all machinery essentia

23、l for the safe operation of the ship to be controlled from a local position, even in the case of failure in any part of the automatic or remote control system. Jimei university4. It shall be possible for al5. The design of the remote automatic control system shall be such that in case of its failure

24、 an alarm will be given. Jimei university5. The design of the remote auUnless the Administration considers it impracticable, the present speed and direction of thrust of the propeller shall be maintained until local control is in operation. Jimei universityUnless the Administration cons6. Indicators

25、 shall be fitted on the navigating bridge for:a) propeller speed and direction of rotation in the case of fixed pitch propeller; orJimei university6. Indicators shall be fitted b) propeller speed and pitch position in the case of controllable pitch propeller.Jimei universityb) propeller speed and pi

26、tch 7. The number of consecutive(连续的，连贯的) automatic attempts which fail to produce a start shall be limited to safeguard sufficient starting air pressure. Jimei university7. The number of consecutive(连An alarm shall be provided to indicate low starting air pressure set at a level which still permits

27、 starting operations of the propulsion machinery. Jimei universityAn alarm shall be provided to B. BRIDGE CONTROL SYSTEMS (U. M. S.)Jimei universityB. BRIDGE CONTROL SYSTEMS (U. Bridge control of propulsion plant and propulsion control systems centralized in a control room are now normal provision.

28、Jimei universityBridge control of propulsion pSystems provided vary to some extent to suit the particular engine requirements of the major designs, e.g. Burmeister & Wain or Doxford or MAN etc. Jimei universitySystems provided vary to some As a typical example, the standard design for Sulzer RND eng

29、ine provides engine control from the wheelhouse telegraph with fully automatic direction selection, starting, speed control and safety devices. Jimei universityAs a typical example, the stanTheir Type SBC7 bridge console and control console panels are shown on Fig. 10 and 11, these being indicative(

30、指示的) of the instrumentation involved. Jimei universityTheir Type SBC7 bridge consoleIn addition to the parts listed a non-reply telegraph(非应答式车钟) receiver or telegraph indicator panel is mounted adjacent to the engine emergency manoeuvering controls. Jimei universityIn addition to the parts listeC.

31、ALARM SYSTEM Jimei universityC. ALARM SYSTEM Jimei universiAn alarm system shall be provided indicating any fault requiring attention and shall: Jimei universityAn alarm system shall be provi1. be capable of sounding an audible alarm in the main machinery control room or at the propulsion machinery

32、control position, Jimei university1. be capable of sounding an aand indicate visually each separate alarm function at a suitable positionJimei universityand indicate visually each sep2. have a connection to the engineers rooms and to each of the engineers cabins through a selector switch, to ensure

33、connection to at least one of those cabins. Jimei university2. have a connection to the enAdministrations may permit equivalent arrangementsJimei universityAdministrations may permit equ3. activate an audible and visual alarm on the navigating bridge for any situation which requires action by or att

34、ention of the officer on watch;Jimei university3. activate an audible and vis4. as far as is practicable, be designed on the fail-to-safety principle; and Jimei university4. as far as is practicable, b5. activate the engineers alarm if an alarm function has not received attention locally at limited

35、time. Jimei university5. activate the engineers alaThe alarm system shall be continuously powered and shall have an automatic change-over to a stand-by power supply in case of loss of normal power supply. Jimei universityThe alarm system shall be contD. AUTOMATION ON SHIPS Jimei universityD. AUTOMAT

36、ION ON SHIPS Jimei uTypical example of automation on ships are fire detection and extinguishing systems; emergency lighting systems; Jimei universityTypical example of automation automatic start of standby pumps supplying lubricating oil and fuel oil to the propulsion machinery; and automatic speed

37、reduction or stopping of propulsion machinery when faults are detected. Jimei universityautomatic start of standby pumFurther improvements can be achieved in an integrated control system by incorporating digital data processing equipment-that is, a computer. Jimei universityFurther improvements can

38、be acThis remarkable machine can provide rapid and accurate supervision, analysis, recording and display of the conditions it is monitoring. Jimei universityThis remarkable machine can prIn so doing, it serves as an extremely valuable aid to human judgement. Jimei universityIn so doing, it serves as

39、 an eBut in some control systems the computer is arranged to make the necessary decision and take the necessary action without human intervention. This is called direct digital control. Jimei universityBut in some control systems thIntegrated bridge-engine room control systems are now available that

40、 combine the functions of engine room monitoring and control, collision avoidance, docking and manoervering, navigation, and cargo handling. Jimei universityIntegrated bridge-engine room These systems include one or several computers for facilitating data inquisition, processing, logging and display

41、, and for exerting some degree of direct digital control over the machinery. Jimei universityThese systems include one or sE. REMOTE CONTROL AND AUTOMATION OF LARGE ARINE DIESEL ENGINES Jimei universityE. REMOTE CONTROL AND AUTThe simplest way to achieve remote control of large marine diesel engines

42、 is by providing a separate manoeuvring stand beside, or in front of, the engine. Jimei universityThe simplest way to achieve reMostly, this stand has been developed into a large desk or console, comprising all the instruments needed for manoeuvring and serving the main and auxiliary engines, togeth

43、er with all the measuring instruments. Jimei universityMostly, this stand has been deFurther automation requires remote control from any place in the engine room or a special control room and, in many cases, from the bridge. Jimei universityFurther automation requires reToday automation is being dev

44、eloped with the purpose of relieving the operators, and especially the men on the bridge, from paying any attention to levers, hand-wheels, instruments, etc. Jimei universityToday automation is being deveHowever, in most cases a manoeuvring stand at the engine is still left for direct operation of t

45、he engine in case of emergency. Jimei universityHowever, in most cases a manoeThere are three remote control arrangements in general use, (a) from engine control room to engine; (b) from bridge to engine; (c) from both bridge and engine control room to engine. Jimei universityThere are three remote

46、controlThe remote control is pneumatic up to 3O meters and electro-pneumatic beyond this distance.Jimei universityThe remote control is pneumatiHere is given one of the remote control types applied to large marine diesel engine. It is built on pneumatic elements with a relatively simple electronic c

47、ontrol for fine speed adjustment. Jimei universityHere is given one of the remotThe system provides automatic control of the main engine from the bridge and manual control from the control room in the engine room. Jimei universityThe system provides automatic The pneumatic system is most reliable; a

48、nd the electronic system is simple and easily maintained. Jimei universityThe pneumatic system is most rThe electronic system contains only three insert type units; Jimei universityThe electronic system containsone is a power unit containing a transformer and a rectifier to give 24 V dc and 115 and

49、200 V ac; Jimei universityone is a power unit containingthe second is a programme unit for various fine speed adjustments; and the third is an electronic control for the electric step motor. Jimei universitythe second is a programme unitEven if all electronics should fail, bridge control with the pn

50、eumatic system is possible. Jimei universityEven if all electronics shouldWhen the officer on the bridge moves a selector switch on the bridge console to Bridge Control, the Bridge Control on the control room telegraph lights up and an alarm sounds on the telegraph until acknowledged. Jimei universityWhen the officer on the bridgeThere are also two buttons marked Fine Setting up and Fine Setting down on the bridge console. Jimei universityThere are also two buttons marWhen the ship is man