Multicar-Elevator Group Control Algorithm for Interference Prevention and Optimal Call Allocation

Abstract

The need to improve the efficiency of elevator systems is growing as higher buildings are being constructed. Increasing the number of elevators within a building is a commonly used strategy to achieve a greater passenger transportation capacity. However, the area required by elevator shafts limits the number of elevators that can be built. Multicar-elevator (MCE) systems, consisting of two or more elevator cars within a single shaft, have been proposed as a solution to increase the passenger transportation capacity without requiring extra space within the building. Yet, the implementation of MCEs requires the prevention of interference among elevator cars, which traditional group control methods are unable to achieve. Therefore, an MCE group control method that can perform an efficient allocation of service calls while preventing interference among cars is required. In this paper, we propose an MCE group control algorithm implementing an interference risk evaluation, a schedule-completion-time minimization function, and idle-car parking strategies. With our algorithm, we aim to achieve an efficient allocation of calls and prevent interference, but without restricting the operation of elevator cars like the existing MCE group control methods do. The simulation results show that our algorithm has a good performance under low and medium passenger arrival rates.