The rapid development of China's elevator industry, the rapid development of the elevator industry at the same time, the issue of high power consumption can not be ignored. According to incomplete statistics, among the more than 600,000 elevators in use nationwide in 2013, energy-saving elevators accounted for only 1.92%. By 2015, if all elevators in China still use non-energy-saving elevators, China's elevators will consume about 80 billion kilowatt-hours more, equivalent to one-year power generation of Three Gorges Power Station. Figures show how important elevator energy conservation is. The following is the elevator energy-saving six ways and six new energy-saving technologies are introduced
Variable speed technology in operation
The rated power of an elevator traction motor is designed based on the maximum power output of the traction motor under full load or no load. When the car, the heavy weight of the same conditions, the traction motor in theory only to overcome the traction wheel static pressure friction, the output power is not full and there is still margin.
Under the premise of constant motor power, when the car and heavy weight are in consistent condition, the elevator speed can be relatively increased according to the change of the number of passengers. Compared with the traditional elevator operating at rated speed, the use of variable speed technology can be properly increased elevator speed (the original speed of about 1.6 times the original speed). This relative reduction in passenger waiting and boarding time, but also the contribution to energy saving.
Energy feedback technology
The energy feedback technology can convert the regenerative energy generated by the car at light load or full load downwards and the kinetic energy generated by motor braking through multiple rectification technologies into electric energy and feed it back to the grid for use by other electrical devices in the same local area network. Reduce the energy consumption of the device in line with the green. According to this principle, an experimental "hybrid power elevator" has been developed to store the regenerated power in a special "battery" for use by other electrical equipment in the power grid.
Single well double car operation technology
In order to improve the elevator carrying efficiency and the utilization ratio of hoistways in high-rise buildings, single-shaft dual-car technology has emerged in recent years. According to the location and operating conditions of the car can be divided into super double story car, adjustable positive double car linkage and double car independent operation of three types.
Single well double car technology works on the same shaft in the two independent car, the intelligent control system through the sensor to monitor the two car position to prevent collisions, it can be independent of safe operation And play the role of increasing the carrying capacity to achieve energy saving.
The purpose of layer selection of intelligent technology
By intelligentizing diversified operation dispatching at the destination level, it is possible to effectively improve the elevator operating efficiency and reduce the waiting time for passengers or boarding.
The purpose of the selected layer of intelligent technology from the group control unit, the target layer layering device and floor indicators and other modules, based on expert systems, fuzzy logic and neural network control technology, with dynamic decentralized waiting to be picked up, peak self-identification, dynamic partition services, Configure the service layer, deployment strategy can choose and timely forecasting and other functions.
Wireless power transmission and wireless signal transmission technology
Through the wireless power transmission and wireless signal transmission, the elevator car without elevator can not only save the elevator, but also improve the elevator load balance in operation, signal interference, safety performance and a series of safety and energy saving problems.
Elevator cab The escalator connects the cab and elevator room control cabinets to transmit power and signals. Through the mutual interaction between the shaft wall of each layer and the top of the car, the current frequency is increased and a high-frequency magnetic field is generated in the core coil. When the secondary coil of the car approaches, an induced current is generated, and then rectified to DC to charge the battery as the power supply for the elevator car and the landing door.
The elevator car side switch signal is collected by the original signal acquisition device and then hard-wired to the car side wireless signal transmission device. The antenna transceiver sends the signal to the landing door side wireless signal transmission device, and then transmits the signal Connect to the monitoring center. Monitoring center issued to the elevator car side switch signal line is the opposite. In this way, the elevator car has no elevator signal to transmit the wireless signal, so as to achieve the safety and energy saving of the elevator operation.
Reduce standby power consumption
Relevant research departments abroad carried out energy consumption tests on 150,000 running elevators. The report shows that in the elevator energy consumption, the maximum energy consumption is standby energy consumption, standby energy consumption accounts for about 58% of the total energy consumption of the elevator, showing that reducing standby energy consumption has a significant effect on improving energy efficiency of the elevator.
Optimized for reconfiguration
The average load rate of the elevator is about 20% of the rated load, and the currently accepted elevator balance coefficient is 40% -50%. After a large number of test analysis, the industry suggested that the balance factor can be optimized for the traction drive to take 0.35, 0.21 energy recovery device, hydraulic lift take 0.30, indicating that the optimization of the reconfiguration can also reduce the energy consumption of the elevator in operation.
In the elevator energy feedback, energy recovery due to ladder type, the use of frequency and load capacity are different, usually 20% -40%. At present, the national elevator energy standards are not yet introduced. Energy-saving energy-saving is the use of PWM active inverter in the elevator voltage inverter resistance braking unit of the original terminal ERB device installed to achieve the energy feedback effect, this approach is suitable for heavy load, high frequency of use of the elevator .
Reasonable optimization of elevator selection and management
According to the nature of the building, the service object, the use of area, flow and destination, such as the rational allocation of elevator varieties, quantity, operation and parking layout scheme can play a saving effect, is also the most pragmatic approach.
Develop new energy-saving technologies
The application of new technologies such as linear motors, torque inverters and high-efficiency speed reducers in elevators can also save the elevator energy consumption.
Linear motor without any conversion device can be directly converted into linear motion of mechanical energy. A linear motor-driven linear elevator, put into operation in Tokyo, Japan, in 1990 with a payload of 600 kg and a speed of 1.75 m / s with a lifting height of 22.90 m.
The new generation of linear motor drive, no traction rope elevator, no machine room, counterweight and traction rope, with a simple structure, easy maintenance, no noise, pollution and save electricity 60% advantage.
Therefore, the linear motor-driven traction rope elevator may become the future development of high-rise elevator direction.
Elevator energy-saving six ways
Energy conservation of elevators means reducing the consumption of elevators in energy transmission during operation, especially the energy consumption in standby state and improving the operation efficiency of elevators.
Best balance of weight
If the weight of the elevator car and the counterweight are both up and down, the motor only needs to overcome the resistance of the sliding and rotating parts of the elevator. At this moment, the elevator is most energy-saving. However, the load in the elevator car is a variable. If the elevator weight is also changed correspondingly with the load in the car, this energy saving method is the most ideal, but the implementation of this technology is very difficult.
Elevator energy-saving long way to go
China promulgated a series of laws and regulations on energy-saving aspects of elevators. For example, the Ministry of Finance and the National Development and Reform Commission jointly formulated the Opinions on the Implementation of Government Procurement of Energy-saving Products in 2004; the Energy Conservation Law stipulates that energy-saving audits should be implemented on special equipment with high energy consumption And supervision; the State Council "Special Equipment Safety Supervision Ordinance," the elevator has been set as high-energy special equipment, is expected to be included in the government procurement of energy-saving list in the future; AQSIQ to be released on the elevator energy-saving assessment of the "elevator energy efficiency evaluation index And detection method. " The emergence of these laws and regulations, fully reflects our country attaches great importance to energy-saving elevator.
At present, our country has become the most popularized and used energy-saving elevator in the world. Relevant departments said that within a certain period of time, throughout the country, popularize energy-saving elevators. According to the survey, if energy-saving elevators are used in the government buildings and public buildings of government agencies and public buildings in the whole country, the electricity generated by these elevators will be regenerated and reused. According to the average energy-saving rate of 30%, the annual savings will be 9 billion Power. Elevator energy-saving technology promotion task is arduous, but the future is bright.