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As the dynamic measurement of attitude parameter of the steerable drilling tool under vibration may be not accurate, the Least Mean Square (LMS) adaptive filtering algorithm is adopted to filter the influence of drilling tool vibration on the attitude measurement in this paper. The simulation results show that the measurement error of inclination angle after LMS adaptive filtering can be less than 0.1°, and the measurement error of tool face angle is less than 6°, which could effectively improve the attitude measurement accuracy of vertical steerable drilling tools; the results of inverse analysis on actual drilling data show that the actual measurement error of inclination angle after LMS adaptive filtering is about 3°, which is much smaller than that before filtering. It shows that LMS adaptive filtering can effectively filter the vibration signal of drilling tools and greatly improve the dynamic measurement accuracy of the tool attitude.

Based on the multiplication of dynamic eigenvalue coefficient and its dynamic stabilizing capability, fast-scale instability and its asymmetry in power factor correction (PFC) Boost converter with continuous peak current control mode are investigated. To realize higher power factor and less harmonic distortion, a kind of compensation strategy is proposed to make the input current a sinusoidal wave, and it is optimized with parameter resonance. The formulas are deduced,and the overall optimization is carried out. The results of digital simulation shows that the overall compensating strategy has the most powerful dynamic ability to ensure the quick stabilization during every stroboscopic period, and the fast-scale instability is controlled, and the approximate unit power factor and the best compensating effects are obtained finally, resulting in the increase of the conversion efficiency of PFC Boost converter.

The Boost converter with wide range input voltage, operating at both stable section and unstable section, the chaos phenomenon makes the system work unsteadily. Based on continuous current conduction mode, the adjustment and stability control with small sinusoidal parameter perturbation for Boost converter are discussed. The transition process between stable state and unstable state for different perturbation amplitudes are analyzed in detail, the critical transition conditions between stable state and unstable state are deduced, and the stability conditions are also determined. It is shown by digital simulation that sinusoidal parameter perturbation can not only suppress the chaos phenomenon, but also cause the converter originally in steady state to turn into unsteady chaos state. The consistent and appropriate perturbation amplitude range can be selected for the wide range input voltage, so as to ensure the Boost converter to start, be adjusted and operate steadily and reliably.

The bifurcation and chaos should exist in Boost converter while the circuit stability conditions are not satisfied，and the stable state could not be gotten by its self control power. As a kind of OGY method without feedback，the parameter resonance can control the bifurcation and chaos in Boost converter. Based on current controlled Boost circuit，the regulating process and its control power are discussed with the reference value of inductor current as the resonant parameter，and the characteristic parameters in the stable state are also deduced in detail. The control power of parameter resonance with different resonant voltages and the stable characteristic parameters are analyzed for the bifurcation and chaos circuits，so as to realize the precise design of circuit parameters and ensure the Boost converter to work steadily and reliably.