Abahlinzeki bemishini ekhethekile yokuguqula imvamisa yamakheshi bakukhumbuza ukuthi ngokuthuthuka okuqhubekayo kwemboni yezokwakha yaseShayina kanye nokwenza ngcono okuqhubekayo kwezinga lemishini yokwakha, izidingo zekhwalithi yokukhiqiza kanye nezinga lobuchwepheshe eliphelele lamakheshi okwakha nawo ayakhula. Amakheshi ajwayelekile ngokuvamile asebenzisa indlela yokulawula i-contactor relay, eqala ngokuqondile futhi ifake amabhuleki ngokuzenzakalelayo lapho kubhuleka ngempoqo. Umthelela wokuqala kanye ne-braking mkhulu, okwenza umonakalo omkhulu esakhiweni semishini kanye nomshini, futhi izingxenye zikagesi nazo zivame ukulimala. Ngesikhathi esifanayo, kulula ukubangela ukuba izinto eziku-elevator ziwe, okungathinti nje isivinini sokwakha kodwa futhi kuthinte ukusebenza kahle kwebhizinisi lokwakha. Ikakhulukazi kumakheshi okwakha asetshenziswa kabili kubantu nasezimpahleni, kunezingozi ezinkulu zokuphepha. Ngokukhula kwezidingo zabasebenzisi zokusebenza kanye nokuphepha kwamakheshi okwakha, izindlela zokulawula zendabuko ziya ngokuya zinganele.
In view of the above reasons, professional manufacturers at home and abroad have made many new acceleration application attempts in the lifting speed regulation of elevators, such as using multi-stage electric motors for voltage regulation and speed regulation, and introducing variable frequency speed regulation. Gradually, with the continuous development of frequency conversion technology, it has surpassed any other speed control scheme with absolute advantages and occupies a dominant position. The use of variable frequency speed regulation in elevators has many advantages, such as zero speed holding brakes, which have no wear on the brakes; Any low positioning speed, high leveling accuracy; The smooth transition of speed has no impact on the mechanism and structural components, improving the safety of the elevator; The almost arbitrary wide speed range improves the working efficiency of the elevator; The energy-saving speed regulation method reduces the energy consumption of the system operation. It is precisely because of these obvious characteristics and advantages that frequency converters have been widely used in elevators, which will have important significance for the safe operation of elevators and the reduction of operating energy consumption.
Structure and Control of Elevators:
A construction elevator is a construction machinery that uses a cage (or platform, hopper) to transport people and goods up and down along a guide rail frame or guide rail. It is widely used in construction and other fields, such as industrial and civil buildings, bridge construction, underground construction, large chimney construction, etc. It is an ideal equipment for transporting materials and personnel. As a permanent or semi permanent construction elevator, it can also be used in different occasions such as warehouses and high towers. Vertical transportation is the busiest type of machinery in high-rise building construction and has been recognized as one of the essential key equipment for high-rise building construction.
The main components of the construction elevator are as follows: guide rail frame, lifting cage, transmission system, wall frame, chassis guardrail, electrical system, safety protection device, cable power supply device, etc.
Design of Variable Frequency Speed Control System for Elevators
1. Introduction to the Structure of Variable Frequency Speed Control System
The elevator variable frequency speed regulation system consists of the following parts: disc brake three-phase asynchronous motor, variable frequency speed controller, variable frequency brake unit and brake resistor, linkage platform, electrical protection device, etc. The control process is to operate the speed conversion switch on the linkage platform, select the speed gear, and then output a signal to the frequency converter to change the frequency value, ultimately achieving the purpose of speed regulation.
2. Design points of electronic control system
⑴ Selection of electric motor
Ngemuva kokuthi kunikezwe imingcele eyisisekelo yesistimu yokudlulisa (njengomthamo omkhulu wokuphakamisa, isivinini esiphezulu sokusebenza, njll.) inikezwe, inani lezigaba namandla emoto kagesi linganqunywa futhi libalwe. Indlela yokuphakamisa yekheshi yokwakha kufanele ikhethe injini yefrikhwensi eguquguqukayo elungele ukuqala njalo, umzuzu ophansi we-inertia, kanye ne-torque ephezulu yokuqala. Ukukhethwa kwamandla emoto kufanele kusekelwe kusayizi womthwalo wemishini yokushayela, futhi ifomula yawo yokubala ithi:
P=WV/(η×10-3)(1)
Kufomula, u-W umelela isisindo somthwalo olinganiselwe kanye nesisindo sekheji nentambo
V - Isivinini sokusebenza, m/s;
η - Ukusebenza kahle kwemishini (umkhiqizo wekhono lokudlulisa ingxenye ngayinye yesistimu yokudlulisela).
Ngenxa yesici esingaguquki se-torque ye-torque ye-lifti, i-torque ihlala ingashintshiwe kumaza aphansi, idinga ukuthi isiguquli se-motor ne-frequency sisebenze ngesivinini esiphansi. Ngakho-ke, kuyadingeka ukwandisa amandla e-motor noma ukufaka i-fan yangaphandle yokupholisa.
⑵ Ukukhethwa kwesiguquli semvamisa
Lapho imoto yohlelo isinqunyiwe, ukwakheka kohlelo lokulawula kungaqala. Okokuqala, ukukhethwa kweziguquli zemvamisa. Njengamanje, kunezinhlobo eziningi ze-frequency converters kokubili ngaphakathi nangaphandle, okunomehluko omkhulu ezingeni lokulawula nokuthembeka. Ohlelweni lokudlulisela lamakheshi, kungcono ukukhetha isiguquli semvamisa esinolawulo lwe-vector noma isilawuli se-torque esiqondile, ukusebenza okuzinzile, nokuthembeka okuphezulu. Ngenxa yemikhiqizo ehlukene yeziguquli zefrikhwensi, umthamo wokulayisha ngokweqile kanye nenani lamanje elilinganiselwe leziguquli zemvamisa akuhambisani ngokuphelele ngaphansi kwamandla afanayo. Ngakho-ke, lapho ukhetha umthamo we-converter yemvamisa, akudingekile kuphela ukucabangela amandla alinganisiwe, kodwa futhi nokuqinisekisa ukuthi ukusebenza kwamanje okulinganiselwe kukhulu kunamanje olinganiselwe we-motor. Okuhlangenwe nakho okujwayelekile ukukhetha isiguquli sefrikhwensi esinomthamo wezinga elilodwa elikhulu kunelemoto.
⑶ Ukukhethwa kwe-braking resistor
Njengesistimu yokuguqula imvamisa esetshenziselwa ukuphakamisa, ukugxila komklamo wayo kusekwethembekeni kwesistimu lapho injini isesimweni sokubhuleka impendulo, ngoba ukwehluleka kwesistimu okunjalo kuvame ukwenzeka phakathi nezimo zokusebenza lapho ikheji lehla, njengokugcwala ngokweqile, isivinini esikhulu, nokugingqika. Isistimu yokuguqula imvamisa igcina injini isesimweni sokukhiqiza kuyo yonke inqubo yokwehla kwento esindayo. Amandla kagesi akhiqizwe kabusha abuyiselwa ebhasini le-DC lesiguquli sefrikhwensi, futhi amadivayisi adla amandla njengamayunithi okubhuleka nama-resistors amabhuleki ngokuvamile axhunywa ohlangothini lwe-DC. Kunzima ukunquma amanani aqondile amapharamitha ezigabeni zokuqala zokwakheka kwesistimu. Ngaphambi kokuba umkhiqizo uqedwe, akunakwenzeka ukulinganisa ngokunembile nokubala inertia yokudlulisela yengxenye ngayinye; Ekusetshenzisweni okungokoqobo, izici zokunciphisa isistimu zizoshintsha ngokuya ngezidingo zesayithi. Ngakho ezimweni eziningi, inani lesipiliyoni ngokuvamile liphakathi kuka-40% no-70% wamandla emoto. Inani lokumelana elingu-R le-resistor yokubhuleka libalwa phakathi kwebanga elilandelayo.
3. Ukulungisa iphutha Lohlelo Lokulawula Isivinini Esishintshashintshayo
Ngemuva kokuqinisekisa i-wiring efanele yesifunda esikhulu kanye nesifunda sokulawula, uhlelo luqala amandla ekulungiseni iphutha. Setha amapharamitha enjini ngephaneli yokusebenza kusiguquli sefrikhwensi, bese ukhetha indlela yokuzifundela emile ukuze ubone injini. Ngemuva kokuthi ukuhlonza kuqediwe, setha imodi yokulawula, imvamisa yokuphuma, ukusheshisa nesikhathi sokunciphisa, imodi yokukhipha i-RO1 edluliselwe, imvamisa yokuthola ukukhishwa kwamabhuleki nokukhiya, kanye neminye imingcele ehambisanayo (bheka incwadi yomsebenzisi yesiguquli ngasinye se-frequency ukuze uthole imingcele ethile yokusetha). Ngemuva kokuthi ukulungiselelwa kwepharamitha sekuqediwe, ngokuya ngemithetho ejwayelekile kazwelonke yokuhlola amakheshi okwakha, izigaba ezimbalwa zokungalayishi iphutha, ukulungisa amaphutha okulayisha okulinganiselwe, kanye no-125% wokulungiswa komthwalo olinganiselwe kuzokwenziwa. Ngesikhathi sokulungisa iphutha, uma kukhona into eshelelayo, imvamisa yebhuleki ingalungiswa ngendlela efanele, kodwa akumele isethwe ibe phezulu kakhulu, ngaphandle kwalokho isiguquli sefrikhwensi sijwayele ukubika amaphutha. Ngokuvamile, isethwe ngaphakathi kwe-0.3~2Hz.
4. Ukuphepha ukulungisa iphutha lamakheshi
Ukuphepha kuyizinga elibaluleke kakhulu lamakheshi okwakha, futhi ukuhlolwa kokuphepha kufanele kwenziwe ngokuvumelana namazinga kazwelonke ngesikhathi sokulungisa iphutha lesistimu. Ngesikhathi sokulungisa iphutha lokungenalo umthwalo, kungenzeka ukuhlola ukuthi ukushintshwa komkhawulo wemikhawulo ephezulu nephansi ye-elevator, kanye neminyango yekheji, isebenza ngokuvumelana nezindinganiso zokuklama; Ngemva kokulungisa iphutha kumthwalo olinganiselwe ongu-125%, lungisa isivikeli sokulayisha ngokweqile sibe ngu-110% futhi wenze ukuhlolwa kokugcwala ngokweqile. Ukuhlolwa kokulwa nokuwa kuvame ukubandakanya ukufaka izinto ezisetshenziswayo zokuphepha ezinqamula ukuwa kumakheshi okwakha. Amadivaysi okuphepha okulwa nokuwa ayingxenye ebalulekile yamakheshi okwakha futhi asetshenziselwa ukuqeda izingozi zokuwa kwekheji. Amakheshi asetshenziswa ezindaweni zokwakha kumele ahlolwe ukuwa njalo ezinyangeni ezintathu. Ukuhlolwa kokuwa kungenziwa ngokwandisa imvamisa yokuphuma kwesiguquli semvamisa ukushayela imoto ukushayela ikheji ngesivinini esilingisiwe sokuwa ukuze kubonakale ukuthi idivayisi yokuphepha yokuwa iyasebenza yini.