Research On Elevator Driver Device With Super Capacitor To Store Energy

Though the rapid development of the elevator brings a huge convenience to people's lives, it also causes many problems. The most important issue is the energy consumption. At present, the energy consumption of elevator second only to air-condition, accounts for about 5%-15% in the whole building energy consumption. The elevator as a load of potential energy has a huge energy saving space when it's running. The research on elevator energy-saving technology is urgent today for a serious shortage of resources.At present the main elevator energy-saving technology is considered from five considerations: the using of elevator feedback energy, the elevator drive system, elevator group control, software management and shared DC bus. The elevator feedback energy can be the most significant use of energy. In the using of elevator feedback energy fact, against to the problems of energy feedback, the paper presents a energy-saving programs by installing a super capacitor energy storage device which is connected to the DC bus with a bi-directional DC-DC converter. The program can efficiently store the feedback energy. When required, power to the elevator and its auxiliary devices, achieving the feedback energy is used locally and saving energy; The device can balance the power to reduce the impact on power; avoid the negative impact on the grid when the energy feedback to the grid; In the case of elevator suddenly loses power, super capacitor groups as a UPS, providing power necessary leveling power to elevator. In the elevator drive aspect, the paper uses the direct torque control based on the space voltage vector technology.According to the characteristics of elevator operation mode and energy feedback, proposed the super capacitor energy storage device base on the bi-directional DC-DC converter. In he premise of analysis the mathematical models of super capacitor and the elevator energy conversion curve in typical operating conditions, according to the elevator parameters, design and calculation the super capacitance, voltage values, single selection, single series and parallel combinations and so on. In the control method of super capacitor charging and discharging, according to the different characteristics of the super capacitor charging and discharging, separately used the super capacitor voltage and charging current dual closed-loop control and DC bus voltage and super capacitor voltage dual closed-loop control method. The small signal model of bi-directional DC-DC converter is established, building the simulation model in the environment of MATLAB/Simulink for charging and discharging simulation. The simulation results demonstrate the feasibility of the control program. Based the simulation further experimental verification is executed.In the elevator drive, the direct torque control based the space voltage vector technology is used. The permanent magnet synchronous motor (PMSM) dynamic mathematical model and the basic principles, calculation method of space voltage vector is described. And on this basis, proposed the direct torque control (DTC) of PMSM based on the SVM. The simulation model of the SVM-DTC of PMSM is established in MATLAB/simulation toolbox. The simulation results show that the method has a good dynamic control performance, verify the feasibility of the method.Finally, the overall energy consumption test of energy storage device with super capacitor is carried. The experimental results show that the elevators with super capacitor energy storage device have significant energy saving effect and run smooth.