Study On The Energy Saving Control Technologies Of Variable Frequency Adjustable Speed Drives

Induction Motor Variable Frequency Adjustable Speed Drives,neither in variable frequency variable voltage control mode, or in vector control mode, both are controlled in rated excitation, at torques and/or speeds far from the rated values the efficiency is greatly reduced. To this problem, the energy saving control problem of variable frequency adjustable speed drives is studied in the issue, based on the international study.Firstly, the basic principles of the energy saving control problem of variable frequency adjustable speed drives is summarized, two linear simulation model were established based on Matlab\Simulink7.0 simulation software, main flux saturation and iron loss characteristic of the induction motor(IM) were experimented, an engineering method of identifying the mutual inductance curve is proposed, an non-linear IM simulation model was established. The validity of the three simulation models of IM were verified by the simulation results, the validity and accuracy of the proposed model are verified by the experimental results.Using the nonlinear IM model, four energy saving control methods based on the loss model of Full Loss Model Control(FLMC),Constant Slip Frequency Control(CSFC),Constant Power Factor Control(CPFC),Direct Reducing Voltage Control(DRVC) and one energy saving control method of Full Fuzzy Logic Search Control(FLSC) based on search were simulated in this paper. The validity of the five energy saving control methods were verified by simulation, the software programs based on CPFC,DRVC and FLSC were designed,programmed and experimented analyzed, by eight performance index evaluating,the DRVC method was chose to applied to products. Finally in this paper, according to the performance characteristic of DRVC and FLSC method, a new Hybrid Control method based on DRVC and FLSC was discussed.