Search

The current transmission line robot up and down the line relies on manual lifting, and this method is labor-intensive, dangerous, and requires the assistance of many people. To address this problem, the paper proposes a control method based on UAV-assisted transmission line power line operation robot up and down the line. Aiming at the characteristics of transmission lines, in order to solve the problem of uneven posture and even side-turning when the robot is on line, the robot adopts the way of lifting with four traction ropes driven by the reel, and analyzes the tilting situation that the robot may encounter when it is on line, and puts forward a BP fuzzy neural network PID-based leveling control method, which compares the rapidity and stability of the leveling of the different control methods in the case of perturbation, and solves the problem of uneven posture and side-turning of the robot when it is on line. the problem of uneven attitude. Finally, a robot lifting attitude leveling experiment is carried out in a simulated field to prove the feasibility of the proposed automatic robot up and down line method in practical applications.

In this paper, a combined system of static var compensator (SVC) and active power filter (APF) was proposed. The system has the function of power factor correction, voltage stability, and harmonic suppression. The SVC, which consists of delta-connected thyristor-controlled reactor (TCR) and Y-connected passive power filter (PPF), is mainly for voltage stability and power factor correction. The small rating APF is used to filter harmonics generated by the nonlinear load and the TCR in the SVC and to suppress possible resonance between the grid and the PPFs. The configuration and principle of the combined system were discussed first, and then, the control method of the combined system was presented. An optimal nonlinear proportional-integral control was proposed to improve the dynamic response and decrease the steady-state error of the SVC. Harmonic detection with precompensation method and improved generalized integrator control were proposed to improve the performance of APE The new combined system is compared to classical SVC. It is implemented in a 200-kVA prototype in the laboratory. Simulation and experimental results show that the proposed combined configuration can effectively stabilize system voltage, correct power factor, and suppress harmonic currents. Index Terms--Active power filter (APF), combined system, harmonic suppression, improved generalized integrator control (IGIC), reactive power compensation, static var compactor, voltage stability.

Hybrid activepower filter with injection circuit (IHAPF) shows great promise in reducing harmonics and improving power factor with a relatively low capacity active power filter, but suffers from dc-side voltage instability that inadvertently impacts the compensation performance and safety of the IHAPF. In this paper, two new methods are proposed to overcome this major technical challenge with a hysteretic control and energy release circuit, and a controllable pulsewidth modulation (PWM) rectifier. Modeling, theoretical analysis, and experimental results have verified that both methods can stabilize dc-side voltage within a certain range. A prototype IHAPF system was built incorporating the PWM rectifier dc voltage control scheme, and installed in a 220 kV substation in Southern China. It demonstrated significant improvement in harmonics reduction and power factor. The dc voltage stability issue was also resolved with the new design. Index Terms--Active power filter, dc-side voltage, energy release circuit, harmonic voltage, pulsewidth modulation (PWM) rectifier.

This paper deals with a hybrid active power filter with injection circuit (IHAPF). It shows great promise in reducing harmonics and improving the power factor with a relatively low capacity active power filter. This paper concluded that the stability of the IHAPF based on detection supply current is superior to that of others. To minimize the capacity of IHAPF, an adaptive fuzzy dividing frequency-control method is proposed by analyzing the bode diagram, which consists of two control units: a generalized integrator control unit and fuzzy adjustor unit. The generalized integrator is used for dividing frequency integral control, while fuzzy arithmetic is used for adjusting proportional-integral coefficients timely. And the control method is generally useful and applicable to any other active filters. Compared to other IHAPF control methods, the adaptive fuzzy dividing frequency control shows the advantages of shorter response time and higher control precision. It is implemented in an IHAPF with a 100-kVA APF installed in a copper mill in Northern China. The simulation and experimental results show that the new control method is not only easy to be calculated and implemented, but also very effective in reducing harmonics. Index Terms--Dividing frequency control, fuzzy adjustor, generalized integrator, hybrid active power filter (HAPF).