Module trainer of photovoltaic integrated low voltage grid (PV-LV grid) with a variety load

This research is a simulation of the penetration of renewable energy at the primary source. The entire system is a compound system, especially on the load. Load types provide different voltage and current treatment. The simulation is carried out with a mini-grid device consisting of five buses with interface sensors to monitor voltage and current. Photovoltaic grid module (PV)-LV as a trainer, uses two power sources to supply the load to the voltage distribution network module. The loading scenario h two plans, where the difference lies in the type of inductive load (scenario A) and capacitive (scenario B). The types of load consist of incandescent lamps, fluorescent lamps, energy-saving lamps, drilling machines, and soldering tools. Variations in this load to meet predetermined loading scenarios. The PV measurement results show maximum power generation at noon and flowed to the load trainer via a 300W grid-tie inverter of 191.1W. The average load bus voltage increases for scenario A and scenario B by 1.045% and 1.36%, respectively. The result indicates that the integration of PV in low voltage systems positively impacts the voltage profile for both inductive and capacitive loads. The amount of voltage improvement depends on the value of the active power injection of the PV and the load supplied by the system.

An IOT-Enabled Generator for Power Monitoring and Load Management with Power Factor Improvement

The quality of power supply and reliability play a vital role in the smooth operation and maintenance of commercial use. These requirements have significant applications when dealing with residential areas, hospitals, industries, educational sectors, banks and airports, etc. In this regard, backup diesel generators are considered the most important source for an uninterrupted supply of electricity. However, there is an emergent need to avoid sudden shutdown of generators in the events of overload, shortage of fuel flow, service interval and lagging of power factor. These common problems can be addressed through monitoring of power generator parameters, for instance, real time remote monitoring to measure the health of the generator, the problem of load management due to high demand of power during peak hours and power factor improvement due to exceeding inductive load. In this paper, our proposed architecture—based on an IOT solution—consists of different sensors, namely a current transformer for measuring load, fuel gauge for fuel level monitoring, and temperature measurement with the energy module to determine the power factor of the system. Our proposed system is operated and tested on a real trolley-mounted 25 KVA generator.

A Novel and Cost-Effective Drive Circuit for Supplying a Piezoelectric Ceramic Actuator with Power-Factor-Correction and Soft-Switching Features

This paper proposes a novel and cost-effective drive circuit for supplying a piezoelectric ceramic actuator, which combines a dual boost AC-DC converter with a coupled inductor and a half-bridge resonant DC-AC inverter into a single-stage architecture with power-factor-correction (PFC) and soft-switching characteristics. The coupled inductor of the dual boost AC-DC converter sub-circuit is designed to work in discontinuous conduction mode (DCM), so the PFC function can be realized in the proposed drive circuit. The resonant tank of the half-bridge resonant inverter sub-circuit is designed as an inductive load, so that the two power switches in the presented drive circuit can achieve zero-voltage switching (ZVS) characteristics. A 50W-rated prototype drive circuit providing a piezoelectric ceramic actuator has been successfully implemented in this paper. From the experimental results at 110V input utility-line voltage, the drive circuit has the characteristics of high power factor and low input current total-harmonic-distortion factor, and two power switches have ZVS characteristics. Therefore, satisfactory outcomes from measured results prove the function of the proposed drive circuit.

SIMULATION OF COMMUTATION PROCESSES OF MULTI-LEVEL VOLTAGE INVERTER SWITCHES

An algorithm for controlling of commutator’s transistors of a single-phase multi-level voltage inverter is presented. The structure of the power circuit of the considered converter, in contrast to most existing circuits, does not depend on the levels number of the output curve due to the using of an universal source of levels, which are formed by output capacitors of two pulsed DC-converters. The commutator control algorithm ensures the formation of the required output curve of the inverter and excludes the occurrence of emergency situations during level commutating. Features of the converter and commutator operation in modes of active power transmission from pulse converters to the load and perception of the reactive power of the inverter load by them are considered. The commutator operation algorithm determines the sequence of control pulses, applied to the base of transistors, the sequence being synchronized with the process of the output voltage curve forming, as well as the direction of the inverter input current. At the same time, features of the level commutating are considered. They differ in the transition direction in value of level voltages: «up» from a lower value to a higher one and «down» from a higher value to a lower one. The sequence of supply and removal of pulses from control electrodes of switches and commutations caused by them, when the inverter input current is positive, are given. The similar commutating of levels is realized, when the inverter input current is negative. Wherein indexes of switches are rearranged in accordance with the direction replacement of their switching of the commutator circuit. A commutator model is realized using Micro-Cap 12 to demonstrate the operation of the algorithm. The transistor MJ15003 model is used as a commutator’s switch. In the model, output capacitors of pulse converters are represented by voltage sources, an autonomous inverter – by an active inductive load. The commutating from a higher voltage level to a lower one with a positive input current of the inverter is considered as an example. Simulation results confirm the performance of the algorithm.

Spectral analysis of the supply current of the rl load with a voltage regulator based on a pulse-line converter

Pulse-width voltage regulators are gaining increasing use in industry, especially in variable speed drives. At the same time, little research has been done in the field of electromagnetic compatibility (spectral composition of current consumption). The aim of the study is to determine, using computer simulation, the nonsinusoidality of the current consumption with an RL-load from a voltage regulator based on a pulse-width conversion. The study of the spectral composition of the supply current of an active-inductive load with a pulse-width voltage regulator was carried out using the provisions of the theory of electrical circuits of sinusoidal and non-sinusoidal periodic current using computer simulation. To analyze the spectral composition of the supply current of the RL-load with the selected voltage regulator, a simulation computer model was created, which consisted of a three-phase power supply and an RL-load, a rectifier with a transistor switch. The regulation of the applied voltage to the consumer was carried out according to the principle of a pulse-width voltage converter. As a result of studying a model of a regulated power supply based on a pulse-width converter and working on an active-inductive load, it was found that even with an initial voltage of the fundamental harmonic regulator of 34 V, the nonsinusoidality of the consumption current is 0.19%, which corresponds to the quality standard for electricity. It is advisable to use this regulator for a controlled electric drive of ventilation systems with an increased slip motor, for example, in "Climate-4M" units. Key words: semiconductor voltage converter, pulse-width converter, higher harmonics, RL-load

Efficient Power Response Characteristics of 2KVA Low Cost Inverter under Resistive Loads and Inductive Loads

The paper discussed the design of low cost inverter using SG3525A IC and IRF3205 MOSFET in H-Bridge configuration. The implementation of the real construction involved the use of IC SG3525A for generation of output pulses; the totem pole arrangement of transistors was used in the driver section of the inverter to boost signals as well as switching purposes. The H-bridge configuration was employed to effectively switch the four MOSFETs, this switching produced an alternating potential of 220V. Pre-set conditions such as load condition, low battery cut, overcharge cut and constant output were set at 1700W, 10V, 13.3V and 220V respectively so as to ensure effective and long lasting usage of the inverter. The battery used for the operation of the inverter was 12V maintenance free battery in order to reduce the cost of using the inverter. The various tests carried out on this inverter were tests on inductive loads, resistive loads, home appliances, overload condition, low battery and charging control. The aim of this work is to achieve inverter design analysis under resistive loads and inductive loads for efficient power usage at lowest possible cost. This was achieved by connecting various resistive and inductive loads on the inverter. The results show that the system can operate under both the resistive and inductive loads but operates better under resistive loads, the reason for this is that inductive loads always draw large currents during start-ups which always result to power losses. Graphs were plotted and analyzed; the results also showed that this inverter can take up to 1700W of resistive load and inductive load of 1020W. The inverter produced no humming sound from inductive loads and home appliances such as fan, television, refrigerator e.t.c that were within its maximum capacity of 1700W.

Proteus ISIS simulation for power factor calculation using zero crossing detector

One of the important parameters for electrical systems is the power factor (cos phi), which is the ratio of the real power (watt) to the apparent power (volt ampere). The best cos phi value is between 0.85 to 1. A resistive load causes the voltage and current in equal phase angle, while the inductive load causes the current to lag behind the voltage. On the other hand, the capacitive load causes the current to precede the voltage (leading). A simulation to determine the power factor of an electrical network can be done with Proteus ISIS software by creating a phase detection circuit. Automatic control can be done by a microcontroller. This simulation circuit can be used as power factor correction, a trigger angle on SCR trigger for DC motor speed control, for rocket launch angle adjuster, to measure the angle of inclination, and other uses relating to angle adjustments.