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This paper analyzes ratio and phase displacement errors produced by commercial capacitive voltage transformers (CVT) under non-sinusoidal waveforms, as exist in power networks. As power quality measurements in high voltage systems are performed at the low voltage side, it is relevant to know the incidence of the CVT in the results. Additionally, a preliminary proposal to compensate those errors is...
This paper presents a new characterization method to measure the RF power handling of capacitive RF MEMS switches. Historically, the RF power handling was characterized by analyzing the pull-in and release voltage shift under several RF power settings. However, this technique is problematic especially because of possible charging under high DC voltages. We present a new measurement setup that includes...
In this paper, according to the problem of improving power quality in power distribution systems, measurement and analysis of middle Egypt distribution network (MEDN) is proposed as a case study. This work is considered as a part of a research project for developing and improving Egyptian distribution networks. In this paper, the measured results (data) show that the voltage profile disturbances is...
Multilevel cascaded converters for use in battery energy storage systems (BESSs) can utilise parallel-connected dc/dc conversion stages. These stages decouple each battery string voltage from the associated H-bridge capacitor voltage. Decoupling prevents second harmonic current ripple flowing in the batteries and compensates for variation in battery voltage due to state of charge. Instead of parallel-connected...
A new method for transient overvoltage (TOV) measurements in 500kV power system using capacitor voltage transformers (CVTs) is introduced in this paper. It is realized with a voltage sensor installed within the CVT as the low-voltage capacitor C3 connection in series with the high-voltage (HV) capacitor C1 and the median-voltage capacitor C2. Simulations studies and laboratory tests in manufactory...
This paper presents an approach for generating simplified secondary circuit models with limited SCADA and PV micro-inverter measurement data. The proposed method is computationally efficient and can be utilized with typically available measurement data. The method is applied to models of three real U.S. utility feeders with PV micro-inverter measurements. The proposed simplified secondary circuit...
Electrical equipment like motion detectors, time switches, presence sensors, timers, low power LED lamps or LED night lights have real power less than 1 Watt at the AC grid 230V/50Hz. But if we analyze the circuit topology, there are many conventional resistors to limit the inrush current. With an inrush controller with switched transistor we can eliminate the resistors and improve the efficiency.
Power factor losses represent a significant factor of power losses in both industrial and domestic units. Various methods have been devised earlier to tackle this problem. This paper aims to present an indigenous technique and method which could be used for static power factor correction. It is demonstrated in this work that phase difference between voltage and current can be determined using zero...
In this paper, a case-study analysis of radial distribution system of Moscow region is presented. This is a part of a research project on Moscow region in Russia. The purpose of this project is to improve the power quality of an important radial distribution system of Moscow region by measuring and analysis the data of the system; and then solving the problems of power quality in this system. This...
In modern power systems, several conducted disturbances and power quality phenomena are commonly experienced also at medium voltage level. Therefore, voltage and current transducers, which scale voltage/current waveforms down to levels compatible with the measuring instruments, are expected to accurately work over a proper range of amplitudes and frequencies, keeping the signal integrity needed to...
The article describes a new method of measuring the average power consumption of microcontrollers during the execution of the instructions, programs or their fragments. The method provides high accuracy and noise immunity. One of the disadvantages of the method is the methodical error. There is assessed its dependence on energy consumption nonlinearity by microcontroller.
A 16-core voltage-stacked IC integrated with a switched-capacitor DC-DC converter demonstrates efficient power delivery. To overcome inter-layer voltage noise issues, the test chip implements and evaluates the benefits of self-timed clocking and clock-phase interleaving. The integrated converter offers minimum voltage guarantees and further reduces voltage noise.
This paper describes a methodology for field evaluation of large PV system impacts on distribution systems based on data collected from several phasor measurement devices deployed on two distribution feeders. The method utilizes a series of performance indicators and pattern trending approaches to process large amounts of granular data gathered from fielded data acquisition instruments (1 second GPS...
The control of Cascaded H-Bridge (CHB) photovoltaic (PV) systems typically requires the power generated by the PV arrays to be measured. The power measurement is used to generate the reference current to inject power into the grid as well as for Maximum Power Point Tracking (MPPT). The number of current sensors required for high level number systems increases their cost and complexity. Power estimation...
In this paper we present the design of high efficiency low power rectifier for microwave energy harvesting. The proposed circuit is based on a voltage booster formed by a voltage doubler type Latour structure. The circuit topology including parasitic elements and microstrip lines has been studied and optimized for high efficiency energy conversion dedicated to low input power operations (below ??10dBm)...
This paper presents an inverter-level power loss measurement method for semiconductor switching devices in real inverter operation conditions. This method employs an H-bridge dc-dc convertor topology and a low-loss inductive load to improve the loss measurement accuracy. Since only dc measurement is involved, it is simpler and more accurate compared to traditional inverter-level loss measurement methods...
A Microcontroller based power factor correction (PFC) converter is proposed, which is not affected by harmonic distortion in current and voltage wave shapes. This paper describes the design and simulation of a single-phase PFC converter using Atmel's AVR Microcontroller. It involves sensing and measuring the power factor from the load using ADC; implementing faster algorithm to process the data using...
The current paper suggests a structure for smart electrical energy meter for (but not limited to) households. The advantage of the suggested structure is that it allows energy metering at different consumers, where the measuring units derive power from their measuring transformer, omitting the need to break the electrical line of the consumer at the measuring point. Simulation verification and experimental...
Boost PFC converter working in Boundary Conduction Mode is taken as the object of study in this paper. Through analysis of the zero crossing distortion of the input current, the time domain model of the input current is derived. A 200 watts PFC CONVERTER prototype is built. Experimental result shows that the relative error between the calculated value of this method and the tested value of the power...
A distribution management system based on loop analysis method is presented in this paper. Firstly, the configuration of the newly developed DMS system is introduced which accommodates DERs. The realization methods of key functions are presented include state estimation, power flow analysis, network optimization, network restoration and reconfiguration, which are based on loop analysis method. An...
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