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With the rapid development of industrial applications based on modular multilevel converter(MMC), the operation reliability is receiving more and more attention. This paper concentrates on open-circuit fault detection and location(FDL) of sub-modules(SMs), and proposes a new strategy based on machine learning(ML) classifier. According to the analyzation the open-circuit fault characteristics, the proposed strategy selects the voltages of SMs as original features for FDL. In order to construct the dataset as well as reduce the amount of calculation, 9 time-domain features are extracted as the new inputs. A ML model based on random forest is then trained and tested with the dataset, considering FDL as classification. To prove the effectiveness of the proposed strategy, the MMC models are built both in the simulations and experiments.

Open-circuit fault of sub-module (SM) attracts more attention with the increasing applications of modular multilevel converter (MMC). To diagnose the SM open-circuit fault in MMC, this paper proposes a fault detection and location (FDL) method based on machine learning (ML). According to the open-circuit fault characteristics, the SM capacitor voltages are selected as the key indicator for anomaly detection model. A method of time-domain feature extraction from voltages is then introduced to construct the dataset for the model. After trained with the samples, the model based on multivariate Gaussian distribution can realize FDL by making predictions for anomaly detection and tracing back the predicted faulty SM. The proposed method can locate the faulty SM accurately without extra sensors or mathematical model of circuit. The results on a simulation of 21-level three-phase MMC present that the anomaly detection model achieves high FDL accuracy as well as low false alarm rate.

Because of the increasing mobility of air targets and the trend of heavy using of UAV in the future, the paper analyzes the parameters and ballistic characteristics of the proportional guidance method based on the revised idea of proportional guidance. The method has certain defects in the face of high maneuvering targets, so we have derived a kind of modified proportional guidance law, and designed a new modified proportional guidance law which can effectively overcome the target maneuvering interference. The digital simulation results show that the modified guidance law can effectively overcome the interference factors such as target maneuvering, and it is easy to implement in engineering.

A new guidance law with terminal angle constraint is presented for the midcourse guidance of anti-hypersonic missiles, thus to realize a near head-on scenario at the start of terminal phase. The proposed differentiator-based outputfeedback sliding mode guidance law is derived from supertwistbased differentiator and prescribed convergence law for secondorder sliding mode controller. Considering nonlinear dynamics of planar engagement, relative range and its derivative, line-of-sight angle and a guess of maximum target maneuverability is required for the implementation of new guidance law, information can always be available through data link from ground-based or air-based platforms. Fast convergence of line-of-sight angular rate as well as flight path angle can be expected. Simulation results validate the effectiveness of new guidance law against various target maneuvers and also illustrate the superiority when compared to conventional guidance laws.

To intercept higher-speed maneuvering target, interception modes are analyzed and head-on posture with maneuverable advantage of interceptor is determined to be the prerequisite. A differential game-based guidance law is proposed under the framework of model predictive control. Gradient-iteration algorithm subject to input constraints is implemented for on-line optimization with respect to a composite objective functional consisting of line-of-sight rate and fuel consumption. Algorithm’s effectiveness for obtaining saddle points of the game is derived on some preconditions. The numerical simulation results show the importance of choosing suitable cost weights and validate the performance of the guidance law. The accessible zone against higher-speed maneuvering penetrator involving varying initial conditions is computed by assuming the other vehicle moves optimally.

The electric heating technology applications is paid more and more attention by oil companies in the oil fields, solving the problem of low efficiency of dealing with high viscosity oil in some of the oil filed. To solve the problem of low heating efficiency of the heating device in a big area, in this paper, based on the development of offshore oil heater is mentioned. The induction heating technology in the electric heating process was introduced. And a special copper is used as its conductive material, at the same time, between the tubing and the heating coils with a special medium high heat. The device is an electric heating device for the separation of oil and sands for oil fields, discussing the process of its work, especially; hardware is made for the calculation of the corresponding. The new heating device that can adapt to the complex environment in oil filed. It has a new structure, high thermal efficiency, easy Installation, maintenance and use as a good oil heating equipment.

In this paper, we present a design of Quasi-Delay-Insensitive Dual-Rail (QDI-DR) asynchronous FIR low-pass filter working in subthreshold region. The filter is implemented in 0.13μm standard CMOS technology and is able to operate with variations of voltages, temperatures and processes. Postlayout simulation shows the design achieves the lowest operating voltage of 170mV with a speed of 2.5kHz. The most energy-efficient point occurs at 250mV with a Power-Delay Product (PDP) of 2.53pJ.

The requirement for controlling lunar lander in the powered descending phase is analyzed in the paper. With suboptimal minimum fuel considered first, the expected non-iterative calculation formulas of the attitude angles are accquired. The explicit guidance project in relevance with the state variables and terminal restrict are deduced. According to deflection between the real attitude angles and the desired attitude angles, the attitude tracking system is designed by adopting the method of exponent reaching law and chattering reducing of boundary layers based on variable structure control with sliding mode. The simulation results show that the control system can complete flying mission in the powered descending phase, and has good robustness and adaptability as well.

In this paper, we propose a novel design of quasi-delay-insensitive dual-rail asynchronous adder working at subthreshold region using 0.13µm standard CMOS technologies. Power Delay Product (PDP) as measure of merit is used for comparison with other recent published subthreshold adders. Low-power consumption, low PDP and high robustness are demonstrated.