Modeling and Analysis of Standalone Inverter-Based Microgrid with Grid-Supporting Voltage-Source Control under Changing Load

This paper presents the collective operation and comparative assessment of artificial neural network (ANN)-based adaptive controller with detuned-inductor capacitor (LC) filter facility in grid-tied voltage source control (VSC) system. In order to facilitate proper shaping of VSC outputs and to avoid voltage surge or current surge issues that may occur during the synchronization, the controlling action should reflect importance of total impedance (Zt) effect for: (i) accurate online weight updating, (ii) generation of correct references for proper shaping of VSC outputs, (iii) accurate assessment and exclusion of current harmonics and (iv) robust in defending any system perturbation. This impedance is taken into consideration during the run-time weight updation process through extended control steps in order to pass over various losses that certainly occurs in transformers, filters, line parameters and so forth. Performance of the system is well improved with an inclusion of total impedance (Zt) measured between the VSC and point of common coupling (PCC). A detuned-LC filter is predominantly intended for reactive power compensation, power factor correction, prompt and accurate alleviation of the harmonics. A comparative assessment in between enhanced and conventional adaptive controllers that are designed in MATLAB/Simulink clarifies the robust performances of the proposed control design under sundry system turbulences. The verification of the proposed enhanced controller is approved with the hardware results obtained using dSPACE RTI 1202 kit.

Download Full-text

Modeling and Analysis of the Self-powered Device for Wireless Heart Rate Measurement

10.20944/preprints201907.0272.v1 ◽

2019 ◽

Author(s):

Aripriharta Aripriharta ◽

Muladi Muladi ◽

Nandang Mufti ◽

ilham ari elbaith Zaeni ◽

I Made Wirawan ◽

...

Keyword(s):

Heart Rate ◽

Circuit Model ◽

The Self ◽

Voltage Source ◽

Storage Device ◽

Rate Measurement ◽

Modeling And Analysis ◽

Piezoelectric Energy ◽

Heart Rate Measurement ◽

Self Powered

A new circuit model of the self-powered device for heart rate measurement is presented in this paper. This device consists of piezoelectric energy harvester (PEH), power management circuit (PMC) with energy storage, microcontroller, Photoplethysmography (PPG) sensor, and Wi-Fi module. The PEH is placed under the insole to harvest the pressure energy from human foot-step to generate ac power. In our model, a PEH is represented by sine voltage source, where its parameters were taken from experiments with 20 volunteers. The PMC is simplified by a switch with gain δ placed in series with the main circuit. The model of the main circuit is RC elements in parallel, where C is the capacitance of the storage device, and R is the equivalent parallel resistance of the microcontroller, PPG sensor, and Wi-Fi modules, respectively. The value of R depends on the power and current absorbed by those modules during sleep, deep sleep, sense, and transmit modes which collected from the datasheet. Finally, the proposed circuit model of the self-powered device was built and simulated in SPICE. The simulation results were compared with the laboratory experiment using commercial devices. Based on the results, the proposed model had small gaps compared to the real self-powered devices in terms of average current, voltage, power and efficiency.

Download Full-text