Internal Power Supply Research Articles

Indigenous Development of MIC-Based C-Band Dual Chain Down Converter Unit for GEOSAT- Spacecraft Checkout System

As part of miniaturization, the development work for the C-band dual-chain down converter, which is extensively used in TM (Telemetry) data acquisition system in GEOSAT spacecraft checkout system has been taken up in MIC (Microwave Integrated Circuit) approach using microstrip line structure. A prototype unit is realized using standard surface mount devices (SMD) and few indigenously developed MIC components namely, the directional couplers, the power dividers etc. The MIC-based down converter module, which forms the heart of the unit is housed in an Aluminium milled box having the dimension of 150 x 150 x 25 mm3. Except internal Local Oscillator (LO), RF Switches and Power supply, all other circuitry are mounted withinthis milled box which is housed in 1U chassis. It meets all the requirements of a conventional down converter. The paper describes the salient features of the unit, its detailed design approach and realization plan and finally the test and evaluation results of the prototype unit developed indigenously.

Experimental study of a turnstile aperiodic HF-band antenna with a terminal load in the form of a near ground four-arm spiral antenna

It is known that the energy characteristics of four-arm spiral near ground antennas with internal power supply (at the geometric center) vary significantly depending on the order of excitation of their inputs. When excitation of the arms of such antennas in the cross-polarization mode, their efficiency of radiating electromagnetic waves decreases by an order of magnitude or more; the article proposes an excitation method that is free of this drawback. The aim of the article is an experimental study of the comparative effectiveness of a near ground four-arm spiral antenna of the HF-band and the antenna system it is part of, when changing its excitation type (from internal to external) and mode (main and cross-polarization). A detailed description of the design of the antenna system and the method of implementing the excitation of its emitters are proposed. The proposed design of a phase-shifting device based on a Butler matrix can be used for effective electromagnetic waves radiation or reception by an antenna system of both right and left circular polarization. The results of the analysis of methods for excitation of a near ground four-arm spiral antenna presented in the article can be used in the design or modernization of antenna systems of ionosondes or radio centers with increasing their efficiency.

Research on day-ahead and intraday scheduling strategy of distribution network based on dynamic partitioning

With the massive participation of new energy in the operation of distribution network (DN), the uncertainties arising from both load and renewable generation have brought challenges to its secure and reliable operation. In this paper, a model of day-ahead and intraday optimal scheduling based on dynamic partitioning (DP) of DN is constructed to realize the refinement of operation in both temporal and spatial dimensions, as well as to improve the reliability of system operation. For the strong fluctuation characteristics of the source-load in DN, the DP is achieved under the premise that the partition structure in each period is tight and the internal power supply has the ability to balance the power fluctuations. In order to improve the regional autonomy of DN, a day-ahead multi-objective optimal scheduling model is constructed based on the DP with the optimization objectives of weak inter-partition power coupling, lowest deficiency rate of flexibility, and lowest operating cost. And a scheme for articulation is proposed to ensure the effective guidance of day-ahead for intraday. Then the intraday dispatch model is constructed by shifting the focus to the incorporate characteristics of DP and quickly smooth the net load fluctuations. Finally, the performance and reliability of the proposed models are verified via case studies.

Estimation of an Extent of Sinusoidal Voltage Waveform Distortion Using Parametric and Nonparametric Multiple-Hypothesis Sequential Testing in Devices for Automatic Control of Power Quality Indices

Deviations of power quality indices (PQI) from standard values in power supply systems of industrial consumers lead to defective products, complete shutdown of production processes, and significant damage. At the same time, the PQI requirements vary depending on the industrial consumer, which is due to different kinds, types, and composition of essential electrical loads. To ensure their reliable operation, it is crucial to introduce automatic PQI control devices, which evaluate the extent of distortion of the sinusoidal voltage waveform of a three-phase system. This allows the power dispatchers of grid companies and industrial enterprises to quickly make decisions on the measures to be taken in external and internal power supply networks to ensure that the PQI values are within the acceptable range. This paper proposes the use of an integrated indicator to assess the extent of distortion of the sinusoidal voltage waveform in a three-phase system. This indicator is based on the use of the magnitude of the ratio of complex amplitudes of the forward and reverse rotation of the space vector. In the study discussed, block diagrams of algorithms and flowcharts of automatic PQI control devices are developed, which implement parametric and nonparametric multiple-hypothesis sequential analysis using an integrated indicator. In this case, Palmer’s algorithm and the nearest neighbor method are used. The calculations demonstrate that the developed algorithms have high speed and high performance in detecting deviations of the electrical power quality.

A 65 nm CMOS rail-to-rail auto-zero operational amplifier based on charge pump internal power supply

A high-gain, low-offset, and low-power auto-zero operational amplifier with rail-to-rail input/output is proposed. Based on a time-interleaved charge pump high-voltage on-chip internal power supply, the PMOS differential pair input configuration will achieve a rail-to-rail input range with constant transconductance. Time-interleaved auto-zero continuously eliminates the input offset voltage of the operational amplifier in the time domain. An nA-level bias circuit to realize low power. The operational amplifier circuit is based on a 65 nm CMOS process. Under 1.2V power supply voltage and temperature 27 °C, the input offset voltage of the operational amplifier is 3.16 μV and the input offset current is less than 20 pA. The temperature drift coefficient of offset voltage is 0.005 μV/°C between −40 °C and 90 °C. The variation rate of input transconductance is only 5.6 % among the rail-to-rail input range. The equivalent DC gain is 106.4 dB, the unit gain bandwidth is 0.54 MHz, the phase margin is 76.5°, and the power consumption is about 0.19 mW. The layout area is 0.83 × 0.75 mm2.

Collaborative Energy Optimization of Multiple Chargers Based on Node Collaborative Scheduling

Wireless rechargeable sensor network (WRSN) uses mobile chargers (MCs) to charge sensor nodes wirelessly to solve the energy problems faced by traditional wireless sensor network. In WRSN, mobile charging schemes with multiple MCs supplementing energy are quite common. How to properly plan the MC’s moving path to reduce the charge energy loss and deploy nodes to improve network coverage rate has become a huge research challenge. In this paper, a collaborative energy optimization algorithm (CEOA) is proposed for multiple chargers based on k-mean++ and node collaborative scheduling. The CEOA combines internal energy optimization and external device power supply, effectively prolongs network lifetime, and improves network coverage rate. It uses the k-mean++ to cluster nodes in the network; then, the nodes in the network are scheduled to sleep based on the confident information coverage (CIC) model. Finally, the CEOA uses a main mobile charger to carry multiple auxiliary mobile chargers to charge all the nodes in the cluster. Simulation results show that the proposed algorithm increases the network lifetime by more than 8 times and the coverage rate by about 20%.

16-Cell stackable battery monitoring and management integrated circuit for electric vehicles

High-precision multi-channel battery monitoring integrated circuits (BMICs) assist battery management systems (BMSs) in effectively managing battery data, which is the key to improving the reliability of electric vehicles (EVs). This paper proposes a 16-cell stackable BMIC, in which a complete high-voltage multiplexing scheme and an incremental sigma-delta analog-to-digital converter (ADC) for monitoring. The chip performs two different data conversions in one monitoring instance, and the measurement error of the 16 channels is controlled within ±4 mV during calibration. The power management unit in the chip provides a stable internal module power supply voltage at an input voltage of 80 V, and the quiescent current is lower than 16 μA. As more cells must be stacked in the EV, the chip also supports chip-to-chip connections through current-mode communication to expand the number of stackable batteries. The chip was implemented based on a 0.18 μm BCD process, and the area of the proposed BMIC was 3 × 3 mm2.

Reliable power supply to power consuming units via isolated distributed generation: problematic issues and approaches to their solution

The present study considers solutions to problematic issues concerning the integration of distributed generation facilities into the internal power supply network of power consuming units. The possibility of ensuring reliable power supply using verified models of generating plants and power consuming units is analysed along with a description of principles for the selection of control systems for generating plants. Full-scale measurements recording significant deviations in power quality indicators, were carried out. A total capacity of distributed generation facilities operating as a part of isolated energy districts is estimated at 8.5–9 GW. In addition, in the case of operation as a part of power systems, this capacity is equal to 13.5–14 GW. Therefore, the total capacity of these facilities is 22–23 GW or 9.5–10% of the total capacity of all generating facilities in Russia. The necessity of using verified mathematical models of generating plants, as well as main synchronous and asynchronous motors, along with the correct consideration of rotated mechanism types and real load factors, is substantiated. Principles for selecting the excitation systems of generating plants, as well as coordinating parameter settings for relay protection devices in generating plants and other elements in the internal power supply networks of power consuming units are considered. Recommendations regarding the permissibility of commutations and guaranteed correspondence between electric power quality indicators and regulatory requirements in island (autonomous) operating mode are provided. Thus, the need on the part of organizations that have necessary software systems and experience in conducting complex mode calculations to implement projects for integrating distributed generation facilities is substantiated. Here, the volume and complexity of calculations is higher than in the design of standard power plants and power supply systems.

СПОСОБЫ ПОДДЕРЖАНИЯ ЗНАЧЕНИЙ НАПРЯЖЕНИЯ И ЧАСТОТЫ В ДОПУСТИМЫХ ПРЕДЕЛАХ В УСЛОВИЯХ РАСПРЕДЕЛЕННОЙ ГЕНЕРАЦИИ ПРИ РЕЗКОПЕРЕМЕННОМ ХАРАКТЕРЕ НАГРУЗКИ ПОТРЕБИТЕЛЯ

Relevance A promising direction for the development of domestic and foreign electric power industry is distributed generation. Distributed generation is a principle for the development of distribution networks and internal power supply networks of enterprises with a voltage level of up to 110 kV inclusive, in which power plants with an installed capacity of not more than 25 MW are located in close proximity to power consumption nodes. The reasons for the spread of this principle of development of distribution networks include the reduction of losses in the transmission of electricity, the possibility of isolated or autonomous modes of operation of energy districts, and due to the variety and high efficiency of distributed generation generating plants, the ability to use any available energy resources, including renewable energy sources. In conditions of distributed generation, power supply to consumers with a sharply variable nature of the load is difficult, which is associated with significant deviations of the mode parameters and shutdown of generating plants by emergency automatics. The reasons for such a low dynamic stability of generating installations of distributed generation are different and are determined by their operating principle, design and some other factors. The main reasons include incorrectly set operation algorithms and settings of emergency automatics, overheating of the primary engine, low moment of inertia of the turbine, and stochastic nature of power generation. Consumers with a sharply variable nature of the load include not only large industrial enterprises, but also communications enterprises, some agricultural enterprises, and the load of the housing and communal sector. Thus, a sharply variable load is present in many areas of activity and solving the issues of organizing its power supply according to the principle of distributed generation is an urgent problem. Aim of research Review of ways to maintain the mode parameters of the power supply system with distributed generation facilities and consumers with a sharply variable nature of the load. Research methods The studies were carried out using the theory of transient electromechanical processes, the theory of power transmission, and experimental results. Results A review is made of ways to maintain the mode parameters of a power supply system with distributed energy sources within a

МЕТОДИКА ВЫБОРА ПАРАМЕТРОВ ПАССИВНОГО ФИЛЬТРА ДЛЯ ПОВЫШЕНИЯ КАЧЕСТВА ЭЛЕКТРОЭНЕРГИИ В ЭЛЕКТРИЧЕСКИХ СЕТЯХ С АКТИВНЫМИ ВЫПРЯМИТЕЛЯМИ

The relevance Due to the wide spread of compact metallurgical plants, which use powerful drives with frequency converters with active rectifiers (FC-AR), an urgent task has become the fight against resonant phenomena in medium voltage electrical networks, since these converters, despite their significant advantages, have a disadvantage — the deterioration of the quality of electricity in the power supply system 6–35 kV. Existing methods of dealing with resonant phenomena in medium voltage electrical networks, in which non-linear elements are present, such as powerful drives of rolling mills with FC-AR used in power supply systems of metallurgical enterprises, do not always allow changing the situation for the better. One way to solve this problem is to use classic traditional filters. Often, the use of traditional filters to eliminate strong voltage distortions in sections of 6–35 kV does not have the desired effect. The installation of traditional filters is accompanied by additional parasitic current resonances, which amplify the intermediate harmonics. These harmonics multiply the oscillations and strongly distort the voltage shape when the frequency response of the distribution network is superimposed with the region of high-frequency harmonics generated by modern FC-AR. Aim of research The article is devoted to the issues of improving the electromagnetic compatibility (EMC) of FC-AR as part of electric drives of rolling mill stands with an internal power supply system for metallurgical plants in the presence of resonant phenomena through the use of specialized passive filters (SPF). Research methods Methods of theoretical and experimental researches are applied in the work. When studying the causes of the occurrence of resonant phenomena, experimental data obtained in the course of research work at the metallurgical plant JSC Metallurgical Plant Balakovo were used. For the processing of experimental data, mathematical modeling methods were used in the Matlab environment with the Simulink application. Results The significance of the results of the work lies in improving the quality of electricity in the distribution electrical networks of mini-plants with FC-AR in the presence of resonant phenomena in the frequency response of the network through the use of SPF. The implementation of the results of the work is an improvement in quality indicators and, as a result, an increase in the reliability of the operation of all power converters in the internal power supply system and a decrease in emergency situations associated with the failure of power elements. The results of the work were implemented at the metallurgical plant of JSC Metallurgical Plant Balakovo. The quantitative indicator of the technical effect of changing the level of the coefficient of the total harmonic components of the voltage in the general sections of the factory GPP КU is: 1) without the use of SPF КU = 10.26 %; 2) when using SPF КU = 1.42 % (relative change δ КU = –72 %). These results can be used at other compact metallurgical enterprises with extended cable lines of medium voltage 6–35 kV and powerful electric drives with FC-AR.

Possibilities to reduce the impact of vfd on the quality of electric power in the networks of enterprises and the cost of its use

Purpose. Simulation modeling of internal power supply systems and comparative assessment on its basis of the total distortion coefficients of the sinusoidal voltage curve. Methodology. Methods of simulating modeling of internal power supply systems. Numerous methods for processing the obtained results. Methods for calculating the discrete Fourier transform. Findings. To increase the level of automation of technological processes in industrial electrical installations, frequency converters are widely used. Together with all the advantages of using a variable frequency drive, it leads to a distortion of the sinusoidal shape of the voltage graph. The article evaluates the total distortion factor of the sinusoidal voltage curve for two options for constructing an internal network of an industrial enterprise. The proposed solution makes it possible to improve the shape of the voltage curve by reducing the number of non-linear semiconductor elements in the power supply system and reduce the influence of higher harmonic components on the power grid. At the same time, this makes it possible to reduce the cost of using VFD at the enterprise. Originality. Through experimental research, it has been established that the use of a common rectifier in combination with a common DC bus and individual inverters can reduce the total distortion coefficient of the sinusoidal voltage curve. Practical value. The developed simulation models of the workshop network’s operation make it possible to study the indicators of the electric energy quality both in stationary and in transient modes of operation.

A Time-Interleaved Charge Pump Internal Power Supply Generation Circuit

A charge pump internal power supply generation circuit for rail-to-rail operational amplifier is proposed, which combines a non-overlapping clock signal and a time-interleaved boost charge pump to achieve an internal power supply which is higher than the power supply voltage. A voltage follower is used to avoid glitch during time-interleaving switching. The charge pump internal power supply circuit is realized by 0.5μm CMOS process. The simulation results show that the internal power supply circuit of the charge pump can generate an internal power supply signal which is 1.8V higher than the power supply voltage. After applying this internal power supply to the PMOS input folded cascode operational amplifier, the operational amplifier achieves the rail-to-rail input, and the unity gain bandwidth and phase margin are stable.

A 0.000747 %/V, 64.59 dB PSRR CMOS-only voltage reference for ultra-low power WSN applications

An ultra-low power voltage reference with ultra-low line sensitivity (LS) and high power supply reject ratio (PSRR) for wireless sensor network (WSN) applications is proposed in this paper. Proposed voltage reference consists only of MOSFETs and the PSRR enhancement block provides a negative feedback loop to adjust the internal power supply voltage and suppress the power supply voltage ripple. By using the gate-to-bulk voltage multiplexing (GVM) current generator and subthreshold technology, the current branch and supply voltage are significantly reduced compared to the previous CMOS reference. The triple-process-trim circuit corrects the temperature coefficient (TC) and reference voltage under different corners, so that the reference has well PVT stability under the whole corners. In addition, a novel multi-start-up circuit is presented to reduce the start time. The simulation results show that, using standard 0.18 µm CMOS process design, the output reference voltage only changes by 1.09 µV in the range of 0.5 V to 1.8 V power supply voltage, and the LS is 0.000747 %/V. The TC is 44.54 ppm/°C across a range of −40 °C to 85 °C. Due to proposed PSRR enhancement structure, a PSRR over −64.59 dB can be obtained at 100 Hz with 35.57 nW power consumption. The simulation results match the theoretical analysis.

Advanced Prototype of an Electrical Control Unit for an MR Damper Powered by Energy Harvested from Vibrations

The work deals with a newly developed prototype of an electrical control unit (ECU) for a magnetorheological (MR) damper powered by energy harvested from vibrations. The ECU, consisting of a rectifying bridge, a driver unit, a microcontroller, and an internal power supply system, is an advanced version of the specially designed processing system for energy harvested from vibrations and the use of this energy to control the MR damper. Unlike a typical MR damper control system in which electrical circuits are powered from an external energy source, the ECU is powered by a part of the energy extracted from a vibrating system using an electromagnetic harvester. However, the excess amount of energy recovered over that necessary to power the MR damper and electrical circuits can be collected in harvested energy storage. The study presents the design concept of the ECU, computer simulations of the in-built driver unit (DU), the method of connecting the ECU with the harvester, the MR damper and displacement sensors, and also describes experimental tests of the engineered unit applied in a vibration reduction system (VRS) with an energy recovery function.

“Green technologies” elements by the individual residential buildings internal electrical networks operation

The article discusses the research results on the internal electrical networks operation of two independent individual residential buildings with a 0.38 kV voltage three-phase electrical input energy. It is established that these electrical networks operation is characterized by a significant currents and voltages unbalance level, which leads to a quality standards violation and electrical energy additional losses increase. When using the computer program “ModulHous”, which algorithm is based on the developed calculation methods, the currents and voltages unbalance calculation was performed. With the use of the MATLAB graphics editor technology, the obtained changes visualization in the currents and voltages unbalance has been implemented. The obtained diagrams analysis made it possible to establish the unbalance power consumption level and its impact on the internal power supply efficiency of the individual residential buildings. A special balancing device is proposed that automatically minimizes unbalancing flows in the internal individual dwellings electrical network. The developed software made it possible to establish the using balancing devices efficiency to improve the quality and reduce electrical energy additional losses in the considered electric networks of individual residential buildings.

Implementation Of Active RFIDs In Inventory Systems

The commoditization of integrated circuits has revolutionized the world of IoT based networks. Supply chain management relies heavily on the application of passive RFID tags for inventory management. However, this technology is outdated and does not provide real-time monitoring for warehouse administration. Moreover, due to the high error rate of traditional passive RFIDs, active RFIDs are graded higher in terms of operational efficiency. The biggest challenge in the deployment of active RFIDs in inventory systems is high power consumption. The passive RFIDs were favored due to their lack of dependency on an internal power supply. The inception of low power long range radio modules has fully transformed the range of applications for active RFIDs. The long range low power active RFIDs are used to develop IoT ecosystems for the purpose of creating a smart supply chain management system. In this research, the hierarchical wireless mesh network consists of three levels; the end node, the concentrator and the gateway. The model takes advantage of low power long range radios to design a system that can monitor and track inventory in a warehouse. The unique circuit has small and compact properties that has the potential to be deployed in real life warehouses.

Microprocessor protection of electrical motors against phase failure in external power supply network

Nonsymmetrical modes in the external power supply network during operation can be caused by several reasons: phase failure due to strong wind or glaciation of overhead power lines, wire burnout due to persistent short circuits, open phase automatic reclosing. In case of open phase condition, the external power supply network, synchronous and asynchronous electric motors are powered along the two phases that are in operation. It leads to the negative sequence current, which poses maximum danger for electric motors, since it causes additional heating and, as a result, premature damage. Therefore, the currently important goal of the project is to study transient processes of the motor load when an open phase mode occurs in the external power supply network and to design microprocessor protection of electrical motors against phase failure in the supply network. To achieve the goal, a computer simulation method is used, based on mathematical models of the elements of electrical network presented as the systems of differential equations in a three-phase coordinate system. The regularities of the flow of transient processes in synchronous and asynchronous electric motors in case of open phase modes in both the internal and external power supply networks have been established. Thus, it is possible to develop an algorithm of the operation of microprocessor protection of electrical motors against phase failure in the external power supply network. The proposed algorithm is based on monitoring the negative sequence current level and the absence of current in one of the phases at the section input. The obtained results show that the proposed algorithm to protect electrical motors against open phase modes in an external power supply network has a high selectivity. Its use as a starting element of the fast-acting automatic transfer switch device allows you to provide uninterrupted power supply for enterprises with a continuous technological process.

The research of Dual MOSFET Parallel technology in Servo drive power

With the development of science and technology, the capacity of high-power power electronic conversion equipment is increasing. The growth rate of current carrying capacity of power electronic converter is lower than that of capacity of high-power power electronic converter. Therefore, the parallel technology of power electronic devices is gradually emerging. In this paper, a double MOSFET parallel technology is proposed, and the feasibility of the scheme is verified by simulation. The scheme can be used in the internal control power supply of power electronic conversion equipment such as driver to realize reliable operation without external control power supply.

RISK ASSESSMENT OF SERVER OUTAGES DUE TO VOLTAGE DIPS IN THE INTERNAL POWER SUPPLY SYSTEM OF A DATA CENTER

The data centers host sensitive electronic devices like servers, memory, hard disks, network devices, etc., which are supplied by the power supply units. The regulated direct current (DC) output of the power supply units fluctuates with input voltage variation since they typically contain single phase switch-mode power supplies. The voltage dips caused by faults in the internal power supply system of the data center can be large enough to violate the Information Technology Industry Council (ITIC) proposed voltage-tolerance guideline. The output of the power supplies, hence the operation of the servers will be interrupted due to such voltage dips. In this paper, the outage probability of the servers caused by the voltage dips are analyzed for different fault location in the internal supply system of a data center.

Вирівнювання графіка навантаження будівлі методом компенсації випадкової складової при підключенні в систему електропостачання групи кінетичних енергонакопичувачів.

The article presents the results of a theoretical study of the process of regulating the load diagram while compensating its random component by connecting a group of kinetic energy storages devices to the power supply system of the administrative building. Daily load diagrams of the administrative building are presented in the form of an additive model. The definition of the law of load distribution is validated. The structure of group of kinetic power storages connecting to the power supply system of administrative building has been developed to compensate the random component of the load diagram. A method of load diagrams equalizing by random component compensating is proposed. Application of the proposed method of load equalizing will allow controlling effectively the capacity of load in the building’s internal power supply system.