Measurement, Control, and Automation

Indoor Localization Based WiFi and BLE Technologies

2022-08-24T07:54:03+07:00

Indoor positioning has attracted commercial developers and researchers in the last few decades. This paper presents an indoor localization system based on both WiFi and BLE technologies at 2.4 GHz. The proposed system uses fingerprinting method with existed advertising channel of WiFi and BLE, 63 reference points and 17 test points. The mean error achieved of 1.6795 m in a very complex indoor environment of 9.2 m x 8.4 m, is a good result compared to similar model considering the equivalent complexity of the region.

Computationally efficient multistep model predictive control in cascaded H-bridge multilevel converter fed induction motor

2022-07-21T11:43:40+07:00

In model predictive control (MPC) strategies for power electronics applications, extending the prediction horizon length has yielded significant benefits. Previous studies have approached the adoption of multistep predictive control (Multistep MPC) for cascaded H-bridge inverters. This method is used very effectively with applications that the prediction horizon is determined. However, when the number of prediction
steps is large, the calculation time will increase significantly. That seems to be the biggest disadvantage when applying the MPC control method. Therefore, this paper proposes an alternative new algorithm that improves the computational time of the predictive control algorithm. This algorithm helps to find control signals faster by parallel search strategy instead of sequential one as in traditional methods. The simulation results demonstrate the calculation speed is significantly faster, the control quality of the two methods is the same, and especially work well for large number of prediction steps applications that the conventional algorithm could not perform.

Initial Position Estimation for Surface Mounted Permanent Magnet Synchro-nous Motor

2022-09-20T06:32:36+07:00

Rotor initial position is required before starting in permanent magnet synchronous motors (PMSM). High-Frequency Injection (HFI) is a common method for initial position estimation as well as during operation. However, the traditional HFI method is only applicable to the interior permanent magnet synchronous motors (IPMSM) because of the significantly different d-axis and q-axis inductance characteristics. Meanwhile, for the surface-mounted permanent mag-net synchronous motors (SPMSM), this distinction is not considerable. To solve this problem, Short Pulses Injection (SPI) uses series pulses that cause an Inductance Saturation Effect and then considers the feedback currents to estimate the rotor position. The disadvantage of this method is that the estimation time depends on the current response speed as well as requires the motor to be at the satu-ration boundary to ensure an apparent saturation effect. This paper proposes a combined method based on the above two methods. Ini-tially, the position of the sector containing the d axis vector is determined by SPI. Then, maintaining the voltage vector causes saturation, then the HFI is used to estimate the initial position. To evaluate the effectiveness, the method is simulated by 3D FEM ANSYS MAXWELL and MATLAB SIMULINK. Compared with existing methods, this method offers accuracy and speed, especially suitable for applications with large moments of inertia.

DC bias elimination for Dual-Active-Bridge DC/DC converter using TMS320F28335

2022-08-17T08:56:21+07:00

This paper proposes an novel simple anti-bias modulation technique for single phase Dual-Active-Bridge DC/DC converters. When a pulsating load occurs, the control efforts of the controller lead to sudden changes in the phase shift. In turn, this cause a momentary unbalance in the positive and negative volt-second product of the transformer. As a consequence, DC bias in the transformer current appears and takes some time to vanish. By some small changes in the setting of the pulse-width-modulation modules of the digital-signal-processor, the bias can be completely eliminated. Theoretical analysis and experimental results show that, it takes only a half of one switching period to remove the bias caused by a pulsating load change without the need of a high sampling speed or any complicated measurements or feedback.

Optimal load control with the connection of solar energy and wind energy sources to the grid

2022-08-24T02:36:48+07:00

This paper uses an artificial neural network to predict the generating capacity of a solar panel, wind turbine, the consumption capacity of the electrical load and the electricity grid price. Then use genetic algorithm and particle swarm optimization to turn on/off of the electrical load to ensure that the nodes voltage and branches current of the low voltage grid are within the allowable range. And ensure that the total cost of selling electricity to the grid from the solar panel and wind turbine minus the total cost of buying electricity from the grid to supply the load is the maximum. This paper also proposes a solution to use smart electric vehicle charging to supply power to the load in case of grid power failure and using monte carlo simulation to calculate the reliability of the grid.

Adaptive Control Design of Interleaved Three-Phase LLC Resonant Converter with Phase-Shedding Technique

2022-08-17T08:54:54+07:00

High efficiency and high power density are becoming increasingly popular in the design requirements of power supplies. In modern power electronics, resonant converters, especially LLC resonance structures are receiving much attention because of their ability to increase the working frequency to reduce the size of passive components while still ensuring high efficiency. Currently, the multi-phase resonant LLC converter is being researched and developed to increase the power capacity and power density of DC/DC converters. In addition, the multi-phase configuration can also perform phase-shedding to improve efficiency under low-load operations. This paper presents a control method using model-based adaptive control (MRAC) to adjust the parameters of the PI controller to improve the dynamic response and quality of the output voltage of the converter in case of converter's parameter change and phase shedding. The adaptive controller responded well and obtained consistently standard results of a 48V voltage source with output voltage ripple is smaller than 200mV and overshoot is smaller than ± 1% over the full operating range. An experimental model of a 3-phase LLC converter with the output power of 3600W is built to verify the design.

Optimization of PID controller by genetic algorithm experiment on delta robot

2022-08-31T02:56:16+07:00

This study aims (i) to design optimal controllers for a Delta robot, and (ii) to experiment with controlling the robot’s end-effector tracking reference trajectories. Delta robot is a parallel robot that has a fairly wide range of uses in industries. There exist many methods for tracking control of the Delta robot, and PID controller is a popular choice because of its low cost of design and experiment. However, arm parameters such as weight, joint, and friction can be changed and affect the operation of the whole system, where PID controllers no longer maintaining control quality. Therefore, this paper presents the analysis, comparison, and evaluation of using the Genetic Algorithm (GA) for self-tuning the PID controller based on criteria of the absolute value of error (IAE). On the other hand, this paper also presents experimental steps to control the Delta robot. Results with GA-PID controller indicate that robot responses archive settling time of about 0.5 (s), and the overshoot is only 3.14 %. Experimental results also show that the proposed algorithm is stable and has a fast response in controlling the motion of the Delta robot.

A new neural iterative learning control approach for position tracking control of robotic manipulators: Theory, simulation, and experiment

2022-08-01T04:53:39+07:00

This paper presents a new effective iterative learning control method for repetitive motion-tracking control problems of robotic manipulators. The controller is comprised of two control loops. In the inner loop, a simple proportional-derivative signal is adopted to stabilize the closed-loop system that facilitates design of the outer loop. Tracking control mission is mainly achieved by a novel iterative control signal designed in the outer loop. The effectiveness of the proposed control method is resulted in from a new iterative design where the iterative signal is flexibly structured from both the current and previous information on the iterative axis. To this end, a neural network is developed to estimate the iterative disturbances using information synthesized from the past and present iterations. A proper inherent function is then employed to connect the iterative-based and time-based control signals. Stability of the overall system is analyzed using absolution regression series criteria. The effectiveness and feasibility of the proposed controller are intensively discussed based on the comparative simulation results and real-time experiments obtained from a 6 degree-of-freedom robot.

Vehicle-to-grid application to improve microgrid operation efficiency

2022-09-17T07:21:07+07:00

Currently, the penetration rate of renewable energy sources (RESs) into the grid is increasing, especially solar and wind energy sources. This brings many benefits but also challenges since these sources inherently have unstable output power because they depend on practical factors. Microgrid (MG) with energy storage systems (ESSs) is a solution to utilize these RESs effectively. However, ESSs like battery storage system has high cost, making application deployment difficult. Therefore, the application vehicle-to-grid (V2G) technology with appropriate control methods to MG will bring more efficiency and potential when electric vehicles (EVs) develop in the future. This article will study and evaluate the effectiveness of using V2G in combination with the droop control method to support islanded MG when encountering power imbalance using Matlab/Simulink. The results show a positive influence of V2G on the stability and operation efficiency of the MG.

Application of Output-based filter for vibration suppression of gantry crane

2022-07-23T03:38:23+07:00

Gantry cranes are widely used in many different fields such as industry or transportation. However, the crane generates unwanted payload vibration during operation, causing operation and safety at work difficulties. There are many crane control methods, but most of them are quite complicated in controller design and practical implementation. This paper proposed the ADRC in combination with Output-based input shaping filter for gantry crane control, in which ADRC is used for precise position control and the filter is designed to reduce the payload sway angle. The advantage of this approach is that only the signals of the system output are required for the filter design. Since most of model information on the target system is not needed, the problem of parameter uncertainty is avoided. Simulation results show that the proposed design can not only suppression the vibrations in the sway angle output but also achieve the desired system response time in position control.