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A new analytical fault diagnosis method is presented for the yaw and yaw rate estimation of a quadrotor. In the existing methods, the faults of the inertial sensors and the measurement sensors are treated separately. The presented method can deal with the faults of both the z-axis gyro and the magnetic sensor by introducing the torque model, which is used as a virtual sensor. The filter design, fault detection, isolation and recovery strategies are discussed. Real flight data is used to validate the proposed approach, showing that both the z-axis gyro fault and the magnetic sensor fault can be detected.

Considering high power and high power factor of space AC-DC energy system, the VIENNA rectification is proposed. The structure of the topology suit for high-power occasions. The operating principles of proposed converter are described and the optimal parameter design of the input inductance and output capacitance parameters are carried out as well. Matlab Simulink is used to simulate the proposed topology, and the simulation results are analyzed. The simulation results demonstrated that the design of the proposed rectifier is able to complete high power factor and dynamic performance.

Abilities of UUV depend on scopes of navigation and cruise duration, while power system plays a significant role in UUV’s issues, which were researched widely in recent years. The contactless power transmission system is coupled coupler connection which achieves a lower efficiency. In this paper, a DCDC charging module of contactless power transmission system is developed and investigated focus on a cascaded LLC resonant converter to obtain higher power level and efficiency at charging system. The operating principles of proposed converter are described and specific design procedures are carried out as well. Eventually, a experimental prototype of proposed converter is implemented to verify the power level and efficiency as designed.

The dynamic model parameter identification is important for unmanned aerial vehicle modeling and control. The unmanned aerial vehicle model parameters are usually identified through wind tunnel experiments, which are complex. In this paper, a model parameter identification method is proposed using the flight data for quadrotors. The parameters of the thrust, drag force, torque, rolling moment and pitching moment are estimated through Kalman filter. Global positioning system and inertial sensors are used as measurements. The observabilities of the model parameters and their degrees of observability are analyzed. Flight experiments are carried out to verify the proposed method. It is shown that the model parameters estimated by the proposed method have good accuracies, demonstrating the validity of the proposed method.

The test of microwave semiconductor chip is currently a hot topic. A miniaturized and highly integrated RF (Radio Frequency) module is designed to test microwave semiconductor chip. Similar to the design concept of synthetic instrument which has an open structure with standard bus and software defined radio, the newly designed integrated RF channel technology realize a variety of RF testing functions. It provides a small and highly integrated common hardware platform with a flexible software platform for re-development of control software. This platform is highly integrated with vector signal generation, vector signal analysis, vector network analysis and noise figure analysis, which can achieve a variety of functional test through dynamic reconfiguration and real-time loading. Multi-stage switch and coupler network are used to route reference signals and reflected signals and transmit signals for vector network analysis. The module receives and generates signals with frequency covering 100k~18GHz. It shares baseband FPGA which makes received signals simultaneously replay in generated channels. The bandwidth reaches 500MHz and supports a variety of vector modulated standards. This module provides a perfect solution to the testing system for microwave semiconductor chip.

In this paper, a drag model-aided fault-tolerant state estimation method is presented for quadrotors. Firstly, the drag model accuracy was improved by modeling an angular rate related item and an angular acceleration related item, which are related with flight maneuver. Then the drag model, light detection and ranging (LIDAR), and inertial measurement unit (IMU) were fused based on the Federal Kalman filter frame. In the filter, the LIDAR estimation fault was detected and isolated, and the disturbance to the drag model was estimated and compensated. Some experiments were carried out, showing that the velocity and position estimation were improved compared with the traditional LIDAR/IMU fusion scheme.

the conventional boost PFC converter was applied in continuous current mode due to current would operate continuously to obtain a high efficiency. A boost PFC converter in DCM control approach was investigated in this paper with a 6kW experiment. The operational principles of proposed DCM boost pfc converter was discussed first. And then relationships between inductor current and duty cycle as well as output voltage with duty cycle are evaluated. A modelling control scheme of boost pfc converter are derived through theoretical analysis and relationships of input current and input voltage. At the end, a 6kW prototype is investigated through combination of theoretical design and calculation, the prototype was able to achieve power factor correction which obtains a power factor of 0.99. In addition, the DCM control approach was demonstrated properly during the research.

AC/DC power converters have been widely implemented in a variety of power systems. Power factor correction (PFC) is considered as one of the significant technologies in AC/DC converters, which has been researched deeply. A new topology of the boost PFC converter is investigated and related operating principles are analysed. The state space modelling approach is applied to evaluate the performance of the boost converter based on the continuous current mode. To demonstrate the stability of the overall system, an optimal design of a compensation network is carried out through the analysis and modelling of the boost PFC converter. The parameters of the proportional integral controller are determined through the theoretical design and mathematical derivation of the voltage loop and current loop. The control strategy and transient response of the converter are verified in MATLAB SIMULINK, which is able to achieve the zero-phase and sinusoidal tracking between input current and input voltage.

A new topology of bridgeless PFC converter is proposed and related operating principles is analyzed as well. State space modeling approach is applied to investigate performance of proposed converter based on continuous current mode. The controller parameters are determined through theoretical design and mathematical derivation of voltage loop and current loop. Control strategy and transient response of converter are verified in Plecs which achieves zero-phase and sinusoidal tracking between input current and input voltage. A 2.5kW bridgeless PFC prototype is developed and experimental results demonstrated the design of proposed topology and control strategy is able to achieve power factor correction.

Nowadays, many fault tolerance navigation methods have been proposed to improve the flight safety. Those methods mainly concern about the faults of GPS, magnetic sensor, and barometer. In this paper, a novel navigation scheme for quadrotors is designed for IMU fault. In the scheme, a dynamic model/ GPS/ magnetic sensor/ barometer integrated navigation system is constructed. Compared with the traditional scheme, the IMU is replaced by the dynamic model. The dynamic model of the quadrotor is used as a virtual sensor, outputting the angular acceleration and velocity acceleration. Simulations are carried out to verify the proposed scheme, showing that the dynamic model can perform as an alternate sensor of the IMU.

Inertial sensors and velocity measurement sensors are commonly used for attitude estimation of quadrotors. In the previous fault-tolerant attitude estimation methods, the two types of sensors' faults are treated separately. When one sensor is detected, the other sensor is assumed to be always healthy. In this paper, the situation is improved by introducing the rolling & pitching moment model of quadrotors. The rolling & pitching moment model, x-axis gyro, y-axis gyro and velocity measurement sensors are fused, forming an analytical redundancy based fault-tolerant filter. The real flight experiment data are used for validation, showing that the faults of x-axis gyro, y-axis gyro and velocity measurement sensors can all be detected and isolated, and the state estimation accuracy is improved compared with the traditional method when gyros are faulty.

In this paper, a novel design approach of the PI controller used for individual DC voltage balancing control of cascaded H-bridge converter-based STATic synchronous COMpensator(STATCOM) is presented. By means of phase shift sinusoidal pulse width modulation, using two control loops(DC voltage control loop and phase angle shift control loop) to ensure DC voltage balance, the proposed approach can calculate parameters of the PI controller of the two control loops relative accurately by finding the relationship of the input and output of PI controller, The simulation results verify that the proposed method has good effects of balancing individual DC voltage, meanwhile, it makes the system a good dynamic performance.