Abstract
II
Abstract
With the development of economy and the advancement of modernization, high-rise
buildings continue to emerge. Elevators have become an indispensable means of
transportation in buildings. In some large shopping malls and hospitals, a single elevator
can no longer meet people's needs. In order to meet the needs of passengers, improve
transportation Efficiency requires the installation of multiple elevators, so the research on
elevator group control systems is very meaningful.
This subject designs a set of PLC-based control system based on six ten-floor
elevators (six elevators, ten-floor single elevator), to complete the passenger traffic as
much as possible within the specified time while minimizing the total running distance of
the elevators. This system needs to control 6 elevators. Each elevator has 10 stay floors.
Each floor has sensors for upward deceleration, downward deceleration and level stop.
These sensors are required to complete the gradual acceleration and deceleration process
when the elevator starts and stops. It maintains a constant speed when running between
floors. In addition, this design also realizes the initialization function of each elevator and
the processing of hedging the top or the bottom of the pier, so that each elevator can reach
the designated floor at the initial time as needed. The focus and difficulty of this design is
that there are many external command signals to be processed, not only that each elevator
has many external sensors, but also that each elevator has dozens of internal and external
call buttons, all of these command states Record the current operation status of the elevator
and the elevator, and determine the target of the elevator according to a certain control
strategy. The realization of the control strategy is to compare the operation status of each
elevator, the floor position and the running time. It is difficult to use the commonly used
ladder diagram (LAD). To solve the problem, Siemens SCL language is introduced here to
complete the design of the control strategy, and the control program is written in
combination with LAD. Finally, the visualization of the control process is realized through
the design of WinCC configuration system.The specific work is as follows:
(1) The modular programming method combined with LAD and SCL language is
used to complete the design and realization of the elevator control program. The
initialization module, floor counting module, call registration module and elevator
operation module are analyzed in detail. The design procedure can ensure the safe and
reliable operation of the elevator.
(2) In order to improve the operation efficiency and reduce the waiting time of
passengers, the various operating conditions that appear in the elevator operation are
classified, and the elevator dispatching scheme is designed respectively, and the design of
the control system based on the minimum waiting time is realized, and the minimum
waiting time is designed. Ladder time evaluation function.
