A velocity profile is the distribution of velocities in the axial direction over a cross-section of circular pipe. In this study, a new ultrasonic flow meter with a modified multi-path configuration, namely, a tomographic ultrasonic flow meter is proposed for the measurement of the flow velocity profile. The flow meter consists of a set of transmitting transducers and a set of receiving transducers placed at different positions on the pipe surroundings. This configuration produces an ultrasonic path in various directions and positions for the flow detection. Transmitting transducers, in sequence, propagate the ultrasound wave to all receiving transducers, and the axial velocity in each ultrasonic path is measured. The average velocity is calculated by using the weighting method. Using the theoretical flow profiles, the tomographic ultrasonic flow meter is simulated in asymmetric flow and compared to both the diametrical and quadrature configurations. The filtered back projection method is employed to reconstruct a flow velocity profile. In the reconstruction process, the flow velocity obtained in each ultrasonic path is used as the projection data. An experiment is also performed in a circular pipe for measuring the air flow velocity profile, in order to validate the proposed flow meter.

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Battery has an important role as energy storage in electricity system utilization such as in electric vehicle and in smart microgrid system. Battery Management System (BMS) is needed to treat the dynamics of energy storage process in the battery in order to improve the performance and extend the life time of battery. In this paper, BMS cell monitoring and protection has been designed and tested for Lithium Ferro Phosphate (LFP) battery cells. The BMS cell monitoring function has been able to measure the battery parameters such as the voltage and current dynamics of each cell. The data taken from the BMS cell monitoring experiment is used to estimate the state of charge (SOC) of battery which is based on coulomb counting with coulomb efficiency ratios. The BMS cell monitoring function has successfully demonstrated the presence of unbalanced cell voltages during both processes of charging and discharging as well. From the analysis, the existence of capacity and energy fades was also investigated for every discharging and charging cycles. Based on the BMS cell protection experiment results, overcharged and over discharged protections have successfully been demonstrated for the battery cells. The charging process is disabled when the voltage of the corresponding battery cell exceeds its high limit (HLIM) at 3.65V, and the battery will be available for charging when all of the cell voltages are below their boundary limits (CAVL) at 3.3V. The discharging process will be disabled when the battery cell voltage is lower than the corresponding low limit (LLIM) at 2.5 V. The battery will be available again when all battery cell voltages are above their discharge available (DAVL) voltage at 2.8V. The proposed BMS cell monitoring and protection has shown its function as a data acquisition system, safety protection, ability to determine and predict the state of charge of the battery, and ability to control the battery charging and discharging.A BMS which flexible enough to protect different types of batteries and can provide all the safety features, has been a recent topic of development and research in electric vehicle and alternative energy systems [3]. As described in [2], a comprehensive BMS should include functions for data acquisition, safety protection, ability to determine and predict the state of the battery, ability to control battery charging and discharging, cell balancing, thermal management, delivery of battery status and the authentication to a user interface, communication with all BMS components and the most important thing is to prolong battery life.

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