Abstract: With the progress and development of the times and society, the number of elevators will inevitably grow rapidly. This article mainly puts forward views on the future development direction and overall trend of elevators, hoping that the new technology will be popularized and used by civilians as soon as possible. Keywords: Elevator, intelligent, green, environmentally friendly and energy-saving
CLC Number: TU857 Document Identification Code: A Article Number: 1672-3791(2012)05(b)-0245-01 Elevator as a means of transportation , has become a symbol of human civilization, and its technological development reflects the progress and civilization of society.
Elevators are indispensable vertical transportation equipment in high-rise buildings. Each large high-rise building is an independent city, such as the 88-story Jinmao Building in Pudong, Shanghai, with a construction area of ??220,000 square meters, 60 elevators, and 18 escalators. This small building integrates finance, commerce, office, and tourism. plays a role in cities that cannot be ignored. The needs of market and social development are the standards for research and development of elevator technology and the development of new products. Some views on several major trends in the development of elevator technology in my country are put forward for reference.
1. Intelligentization of elevators
The needs of today's society have prompted the development of computers and communication technologies, resulting in intelligent systems that can bring together a large amount of the world's information and transmit it quickly. Vertical transportation elevators are also developing in the direction of intelligence. If you want to make an intelligent elevator a safe, comfortable, efficient and high-quality service tool, and interact with systems such as fire protection, security, and building equipment control, you must network with all automated information systems in the building. Serial communication, which is widely used in current elevator control systems, has the advantages of simple wiring and large amount of information transmission. The removal of the input and output circuits on the microcomputer interface board reduces the number of wiring in the hoistway and machine room, greatly improving its reliability and safety. The actual maintenance and repair of elevators has become easier and more time-saving, greatly reducing the error rate.
From the perspective of intelligent control of elevator operation, elevators are required to have high quality service. Advanced scheduling rules should be adopted in the control program to ensure the best elevator dispatching mode for group control management. Many of the current group control elevator algorithms simply aim at "the shortest passenger waiting time". Some elevators use methods that incorporate comprehensive considerations such as fuzzy theory, neural networks, expert systems, etc. into the group control system. Among these factors are factors that affect the psychology of passengers, as well as evaluation decisions about upcoming situations. They are multi-objective control that combines the expert system and the current operating status of the elevator. The elevator control system designed in this way will make the service quality of the elevator better and better. However, the intelligence at this stage is only based on the preset control program and is still a periodic system automatic Although the control is more perfect in terms of service, in many cases, the elevator will still run without load, causing unnecessary waste. Real intelligence should be able to automatically control the elevator according to the situation in the car and the waiting information on each floor. Formulate the optimal movement speed and parking policy for each time, and require the elevator to have an automatic safety detection function so that the elevator itself can detect the fault of the elevator and alarm in time to eliminate it. Intelligence in the true sense needs to be further developed.
The problem of trapped people in elevators has always been a common problem in daily use of elevators. Many elevator manufacturers have added remote monitoring systems to elevators, and installed cameras and communication systems in the elevator car to detect passengers trapped in the car. Can establish contact with building surveillance personnel.
Since this kind of facility is limited to the building where the elevator is located and is in charge of security or other part-time personnel, once a person is trapped in the elevator, professionals must be notified to rescue them. Although current elevator installers generally train users on rescue methods, users still have to Without professionals or corresponding qualifications, it is very easy to cause secondary injury accidents due to improper operation. Nowadays, the emerging remote monitoring service system that integrates communication, fault diagnosis, and computer processing takes the remote monitoring system a step further. It can provide real-time information on the elevator. Operation information and fault information are transmitted to the remote service center (i.e. elevator remote monitoring and maintenance center) through local telephone lines or optical fibers, allowing maintenance personnel to quickly understand the operating status of the elevator, know where the elevator problems are, and even perform remote assistance and control to troubleshoot. The benefits of remote services to users are obvious. The remote monitoring of elevators (integrating audio and video of fault information) enables users to enjoy a complete set of services to ensure the safe operation of elevators. The contracted elevator is always under the monitoring of the remote maintenance monitoring center, and the operating status of the elevator and the nature of the fault can be known at any time. The maintenance personnel already know the maintenance items before going to repair, which reduces the cost and time of maintenance services. This kind of The pre-maintenance after-sales service method is deeply trusted by users abroad, and has also been implemented on a pilot basis in some areas of our country. It is an important direction for the development of my country's elevator industry technology.
2 Energy Saving of Elevators
With the development of science and technology, the shortage of non-renewable resources is increasing, and various electrical appliances and transportation vehicles in life are developing in the direction of energy saving and low carbon. , elevators should not be an exception.
There are many measures to reduce elevator energy consumption. Mainly include: selecting an efficient drive system; reducing the inertia and frictional resistance of the elevator mechanical system, etc.
(1) Permanent magnet synchronous gearless traction machines have now been widely used. From the working principle of permanent magnet synchronous motors, it can be seen that the excitation is provided by permanent magnets. The stator is not required to provide excitation current, so the power factor of the motor can be very high. At the same time, no current passes through the rotor, and there is no rotor loss problem. Generally, the loss is about half lower than that of an asynchronous motor. Since there is no frictional resistance in the worm gear transmission shaft, energy consumption can be further reduced.
(2) In some factories with compact assembly lines, some freight elevators can realize a host machine to drive two cars to run up and down respectively, that is, the counterweight block is eliminated, and goods are transported up and down on both sides at the same time. Another way to reduce energy consumption is to control energy consumption during elevator operation. Utilizing the characteristics of the motor being in the power generation state when the elevator is moving up with no load and descending with full load, the regenerated energy is fed back to the power grid. This energy-saving measure has a significant effect on high-speed elevators.
(3) For traction drive elevators, when the weight of the elevator car is less than the weight of the elevator counterweight, the potential energy of the counterweight is converted into electrical energy when the elevator goes up, that is, generating electricity; when the elevator goes down, a motor is required. Dragging the load consumes electric energy, that is, electric operation. On the contrary, when the weight of the elevator car is greater than the counterweight of the elevator, the upward movement is electric operation and the downward movement is power generation operation. During power generation operation, the frequency converter consumes the electric energy generated by the elevator on the braking resistor, wasting a large amount of electric energy and also generating a large amount of heat. Since the generated electric energy cannot be directly input into the power grid and will cause electric power pollution, a certain control method should be adopted to store the electric energy in a large capacitor for use by other equipment, or feed it back to the inverter after processing such as eliminating harmonics.
(4) Since most domestic elevator machine rooms are currently on the roof (especially in high-rise residential buildings), using solar energy as a supplementary energy source for elevators will also be the future development direction.
In addition, how to reduce or even eliminate oil pollution caused by the use of elevators, including hydraulic oil, transmission oil, lubricating oil, etc., as well as reduce operating noise, reduce electromagnetic radiation generated during the operation of the inverter, These research and developments are necessary to reduce interference to surrounding electrical equipment and instruments.
3 Conclusion
Everyone is happy to see the convenience brought by the development of modern science and technology, and people have been pursuing a more convenient and simple life, but we should prevent and To control the resulting problems such as environmental pollution and resource consumption, only by taking an overall approach can we achieve the simultaneous development and progress of social civilization and the harmonious relationship between man and nature.
References
[1] Zhao Bitao, Xu Yiping. A brief discussion on the application of energy feedback in elevators [J]. China Elevator, 2009, 20(23).
[2] Shi Boning. A brief discussion on the development of elevator technology [J]. Fujian Agricultural Machinery, 2007(3).