| In order to solve the estimated prevalence of frequency regulation saving larger problem, adopted of the independent experiment system of a main mine fan performance, K45-4-№9/18.5kW axial flow main blower performance experiment and noise characteristics under the changeable frequency was carried out. On the basis of the proportion of classical law formula, experimental data under different frequency of fan performance parameters was carried out by least square method, and the best fit with the order was got between air volume and air pressure, shaft power, efficiency, and performance curves were drew of different frequencies; the main air intake fan noise characteristics at different frequencies was studied, and main noise frequency range and spectrum characteristics which air intake noise of the main fan were got. This paper’s main research results are as follows:(1) For main mine fan frequency control of motor speed, the speed should not be less than 50% of the rated speed; At between 50% and 100% of rated speed governor, to the point of maximum air flow experiments optimum operating point, compared to the adjacent frequencies between saving rate, the maximum rate Of 47% was calculated.(2) It was the best fitting effect of 5 times for frequency mine main fan wind pressure-volume curve; and it was the best fitting effect of 4 times for frequency mine main fan shaft power-wind and efficiency-air volume curve.(3) Frequency main fan performance curves at different frequencies similarity, at the same time, it had a significant change in the non-geometric propeties; the non-proportional changes in the law to provide a method for calculating formulas main fan frequency energy rates.(4) It was different for fan performance curve’reasonable work area under different frequency for frequency main fan; shaft power ratio-air volume ratio curve appeared to slow domn geometric increases, and ultimately tends to a limit value, it indicated that it would no longer have energy saving benefits when the main fan frequency conversion to a certain degree; with the frequency became small, the maximum efficiency decreased corresponding frequency main fan performance curve, and the error rate increased to calculate by similar rates.(5) When the frequency was equaled to 50Hz, it is similar for main fan performance curve in both power frequency and frequency conversion of 100%; frequency conversion 100% more energy-saving than running power frequency, and the most large sections between the duty of 2.94%; the efficiency is slightly larger for running power frequency to frequency conversion of 100%, maximum differential efficiency reached 2.93%.(6) Frequency of main fan inlet noise frequency were mainly distributed between 125Hz and 4000Hz, which mainly in the low frequency noise; It had the same trends under different frequencies for noise spectrum characteristic curve, and it had attenuation characteristics for frequency main fan noise, and the noise decreased with the loss of the frequency; In the process of decay, noise rate showed the tendency of increased. |
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