Study And Design Of Elevator Energy Feedback System Based On DsPIC

In conventional elevator controls, DC voltage of converter may have a relatively high raise during the braking period, while a great deal of electricity which collects and stores in capacitors will be subtracted through heating power resistor. Although simple in structure and easy to make, the conventional method can also cause large energy waste. With regard to the loss of energy of elevator on the way down, a grid-connected energy regenerative system is designed and then applied to elevator successfully.Firstly, the thesis presents the problem of traditional converter in application, and the energy regenerative technology is investigated. The backgrounds, development and market prospects of the research on the energy regenerative technology are expounded. Moreover, the research that focuses on distributed power generation system and the grid-connected standard of distributed power generation are also introduced.Secondly, principles of elevator energy feedback device are discussed. Mathematical model based on a double closed-loop control algorithm is presented. The principle and implementation methods of SVPWM strategy are described.Thirdly, the energy feedback device is designed, which consists of main circuit, control circuit and power supply circuit. More specifically, the main circuit includes power device, IGBT module drive-circuit and choke inductances. The control circuit includes signal sampling, voltage synchronizing testing, temperature detection, displaying and other circuits. And the PCB design for all the circuits is completed.Fourthly, to verify the design, a simulation software of NI Multisim is adopted. Furthermore, the inverter system simulation model is built, and Matlab is used to simulate. The simulation results verify the feasibility of control strategy in theory.Finally, adopting the dsPIC30F4011which is produced by MICROCHIP Corporation as the control system’s core processing unit, and using intelligent power module for device’s power on-off element, we develop a new grid-connected energy regenerative system of18.5kW. Based on the system, some experiments are made. The experimental data and waveforms indicate that the elevator energy feedback system based on dsPIC works well and has practical value.