Power Control Unit Research Articles

Microsatellite Power Control and Distribution Unit For The Innosat Platform

The Power Control and Distribution Unit (PCDU) described in this paper is a custom design for the InnoSat satellite platform. Particular attention is given to the architecture, design techniques and general failure mitigation approach that has been adopted to meet the low cost constraints of the platform while maintaining reliability for its entire mission lifetime. A point of importance is the scalability of the design in order to meet different payload power demands from mission to mission while minimizing NRE work. The very important areas of component selection, testing and qualification are also described. In order to quantify some of the topics discussed, the description is mostly focused on the PCDU of the first InnoSat based satellite named MATS and which is expected for launch at 2018.

Разработка и исследование системы управления насосной установкой

Modern is a collection of electric motor, the power converter and control unit. Asynchronous electric commonly used in industry as part of drive pumps, fans, compressors and other mechanisms for which it is important to maintain the engine speed. Infinitely adjustable feed pump in accordance with the current pressure in the water system is an urgent task of automatic control systems of pumping units. Frequency control allows you to control the pump by changing the speed using frequency converters (FC) of electric pumps. FC is one of the modern means of industrial automation and electric power saving. The developed system of water flow regulation is carried out by pressure gauges. The signal from the pressure sensor is compared with the reference signal. In case of inconsistency between these signals PID controller sets the pump impeller speed. Thus, consumers in the absence of line pressure will rise until the signal from the pressure sensor input is not received at a PID controller. That will reduce the pump speed and thus reduce the water flow and engine power. For this automatic control system mathematical model was developed. She was examined by a package SIMULINK MATLAB applications. The purpose of research is to work well, in critical conditions, as well as validation and synthesis of control analysis of transients in the control system. The results of the study are the basis for writing the control program. The algorithm of the pumping unit is designed to provide smooth and accurate regulation of the pressure in the hydraulic network. For the software implementation of this algorithm was used the software package CoDeSys for programmable logic controllers (PLC) OWEN. Application of PLC and developed programs greatly enhance the possibility of installation in question. This system is recommended for use at pumping stations of water supply. It will improve the output characteristics for the consumer, improve the reliability of water supply, to reduce wear of pumping equipment and reduce the cost of consumed electricity.

Functional Study of A Distributed MPPT Power Management System

This paper presents the concept of a control strategy for Solar Array (SA) power regulation using an independent Maximum Power Point Tracking system for each Solar Array section in order to maximize the power extracted from every SA sections. Moreover, it allows to distribute the battery charge current between the power sources in order to evenly divide the switching losses on the power semiconductors of the converters and, thus, extending their life time and to reduce the dissipation power. The proposed strategy can be applied to the Power Control Unit designed for satellites with unregulated power bus architecture. Significant simulation results, obtained using a Matlab/Simulink model, demonstrates the validity of the proposed approach.

Efficiency Optimization and Control of Auxiliary Power Unit for Extended Range Electric Vehicles

How to determine the target engine operation point is a key issue of APU (Auxiliary Power Unit) control, which has a significant influence on fuel consumption of the system. Conventionally, engine operation point was decided by ensuring that the engine works in its maximum efficiency area. However, System efficiency of APU equals the product of engine efficiency and generator efficiency. Conventional method did not pay special attention to the generator efficiency. Based on analysis of how generator efficiency and engine efficiency influence fuel consumption of the system, a fuel optimal control method with consideration of both engine and generator efficiencies is proposed. Numerical models of generator efficiency and engine efficiency are established based on experiment data. An backward optimization algorithm is proposed to calculate optimal engine operation points in order to achieve highest overall efficiency of the engine-generator system. A simulation model is established to validate the optimal algorithm, simulation results indicates that the fuel consumption of the system is reduced by more than three percent after optimization.

Control System Design of an Ultra-small Deep Space Probe

It's a grand opportunity to build new small deep space probe called Shinen2, developed by Kyushu Institute of Technology (KIT), in corporation with the different companies and institutions of engineering in Kagoshima University (Japan), NASA Johnson Space Center, was launched by the rocket H-IIA of Japan Aerospace Exploration Agency (JAXA) with Hayabusa 2, on December 3, 2014 in Tanegashima. This project involves Japanese students and foreigners, permitted a multi-cultural environment and an excellent tools for education. The students are in charge for the design, assembly, integration, tests of the space probe subsystems, and build-up of the existing ground stations facilities for tracking the telemetry data of Shinen2. It will enhance capacity building for the students, and scientific research for upcoming studies. The main approach to carry out the main mission of space probe. In parallel, to develop each subsystem of Shinen2: structure design, system bus architecture including the Communication Control Unit CCU, Power Control Unit PCU specifications, and new Particle Pixel Detector PPD for deep space radiation exploration. The development period for the space probe was only one year; it was extremely a short term. The mass budget and size were strictly limited while requiring a higher reliability. This paper describe a control system design for a small deep space probe which was developed to implement different missions and to satisfy the various requirements listed below.

Development of Power Control Unit for Compact-Class Vehicle

Development of Power Control Unit for Compact-Class Vehicle

Implementation of Tracking System for Human Detection based on Pyroelectric Infrared (PIR) Sensor

paper, tracking of human has described. It has a great importance for detection security and robotics, beside that it can be used for sensing the abnormal behavior of patients in hospital. The aim of this work is to design and implementation of the human detection and tracking system. The design of tracking system has the ability to rotate a camera toward any position in a horizontal axis in both clockwise and anticlockwise directions. The experimental work shows that the direction of rotation can be obtained by determining which one of the four pyroelectric infrared sensor (PIR) is interrupted by the objective. Also the stepper motor controlled the AVR microcontroller based Arduino board which makes the camera track the objective movement. High performance of the proposed system under practice test. To reduce the power consumption of the tracking system a power control unit has been designed, to switch the power off when there is no human detected and switched the power on when a human is detected by a PIR sensor.

Practical Methodology of the Integrated Design and Power Control Unit for SHEV with Multiple Power Sources

Series hybrid electric vehicles (SHEVs) having multiple power sources such as an engine- generator (EnGen), a battery, and an ultra-capacitor require a power control unit with high power density and reliable control operation. However, manufacturing using separate individual power converters has the disadvantage of low power density and requires a large number of power and signal cable wires. It is also difficult to implement the optimal power distribution and fault management algorithm because of the communication delay between the units. In order to address these concerns, this approach presents a design methodology and a power control algorithm of an integrated power converter for the SHEVs powered by multiple power sources. In this work, the design methodology of the integrated power control unit (IPCU) is firstly elaborately described, and then efficient and reliable power distribution algorithms are proposed. The design works are verified with product-level and vehicle-level performance experiments on a 10-ton SHEV.

정지궤도 위성용 전력공급 모듈의 버스 전압 안정화를 위한 최적동작 제어에 관한 연구

In this paper, results of produced PCU(Power Control Unit) prototype was showed by suggesting and maintaining optimal operation status which let the three functional modules automatically operate with its necessity by prioritizing operation process. In order to validate effectiveness of the suggested method, we produced a test PCU and examined the results. PCU consists of S3R(Sequential Switching Shunt Regulator), BCR(Battery Charge Regulator), and BDR(Battery Discharge Regulator): converting photovoltaic power into constant voltage at linked bus voltage; storing dump power in the battery which is an auxiliary energy storage device; and supplying power charged in battery to the load. To maintain its high reliability and optimal condition of these three power conversion modules, each module operates in parallel and stable bus voltage is required to be retained at all-time due to the nature of power supply for satellite.

An Approach to Intelligent Road Lighting System with Renewable Energy Based Power Supply

This paper presents the approach and study of an intelligent electrical consumer, in the analyzed case a road lighting system, powered by renewable energy sources, to achieve energy efficiency. The consumer is equipped with sensors, controlled by a microcontroller unit and can autonomously working. If one of the main objectives is to achieve a better energy efficiency for the electrical consumer, the supply from a renewable energy source makes the consumer environmental friendly. The first aspect of the study is to present the lighting system and the working principle. The LED based lighting modules represents in the modern days the most efficient and reliable lighting system. The renewable energy power system is based on a solar photovoltaic system and represents an alternative supplying way for the lighting systems. Between these two systems, the lighting and the power supply system, a command and control unit has to operate to ensure an accurate system management. The command and control unit has to monitor the available or stored energy from the solar PV system, to read the sensors values that supervise the environment and traffic behavior, and to command the switching of the lighting system for an optimal lighting level and for energy efficiency.

Wear and tear on hydro power turbines – Influence from primary frequency control

Nowadays the importance and need of primary frequency control of hydro power units are significantly increasing, because of the greater proportion of intermittent renewable energy sources and more complex structure of power systems. It brings a problem of increasing wear and tear of turbines. This paper studies this problem by applying numerical simulation and concise theoretical derivation, from the point view of regulation and control. Governor models under opening and power feedback mode are built and validated by measurement data. The core index, guide vane movement, is analyzed based on ideal sinusoidal frequency input and real frequency records. The results show the influences on wear and tear of different factors, e.g. governor parameters, power feedback mode and nonlinear governor factors.

Operational characteristics of hybrid‐powered three‐phase induction motor via synchronous and photovoltaic generators with MPPT utilised by synchronous generator automatic voltage regulator

The operational characteristics of a stand-alone hybrid-powered system are investigated. The sources are conventionally powered synchronous generator and photovoltaic (PV) array. The voltage of the common coupling point is controlled by the automatic voltage regulator of the synchronous generator via which the maximum power point (MPP) of the PV generator is tracked using the open-circuit voltage method. Numerical simulations based on the non-linear dynamical model in dq stationary reference frame are conducted. Power control unit is incorporated to control the driving torque of the synchronous generator once the PV generator becomes unable to meet the requirements of the motor because of reduction of the solar irradiance and/or increase of the load. The analysis includes the response of the system after step changes in the load coupled to the motor and after step changes in the levels of the solar irradiance. The steady-state characteristics of the induction motor in case of hybridisation at various solar intensities are presented and compared with the case when the motor is powered by fixed terminal voltage. It is concluded that the proposed system can run at wide range of operating conditions and robust enough to withstand system parameters step changes.

Analysis of field-stressed modules from a fuel-cell vehicle’s main inverter

This paper presents a reliability study of a directly cooled and an indirectly cooled IGBT module after a test drive of 85.000 Km in a fuel cell electric vehicle. In this case, the car was mainly driven on highway, only a minor part of the distance was driven in urban areas. At the end of the test drive, the power control unit was disassembled and analyzed with regard to the lifetime consumption. First, electrical measurements were carried out and the results were compared with the ones obtained directly after module production (End of Line test). After that, ultrasonic microscopy was performed in order to investigate any delamination in the solder layers. As a third step, an optical inspection was performed to monitor damages in the housing, formation of cracks or degradation of wire bonds. The results show none of the depicted failure modes could be found on the tested power modules after the field test. Obviously, no significant life time consumption could be observed.

Numerical investigation of liquid cooling cold plate for power control unit in fuel cell vehicle

This paper proposed fifteen structure schemes of the liquid-cooled plate for thermal control of the power control unit (PCU) in fuel cell vehicle (FCV). At the given serpentine channel with inconstant width, pin fin arrays with various configurations were arranged to improve the performance of three heating zones with multiple heat sources. Based on the same setup and boundary conditions, numerical simulations were conducted for different schemes. The solutions were validated by grid independence check and comparison with previous researches. Effects of fin geometrical parameters (such as diameter, height, fin pitch and shape) on pressure drop and heat transfer characteristics were investigated. Furthermore, two dimensionless factors ηH and ηP were quantified to evaluate the heat transfer enhancement and pressure drop augmentation. The dimensionless performance evaluation factor PEF was cited to assess overall performance of the cold plate. Based on three factors mentioned above, cooling performances of three heating zones and the whole plate were compared among all schemes. According to the performance comparison, scheme 12 employing circular fins with diameter of 4mm was selected as the optimal solution for the cold plate.

SiC—Emerging Power Device Technology for Next-Generation Electrically Powered Environmentally Friendly Vehicles

The automotive industry is developing a range of electrically powered environmentally friendly vehicles such as hybrid vehicles (HVs), plug-in hybrid vehicles, full electric vehicles, and fuel cell vehicles to help reduce tailpipe CO2 emissions and achieve energy diversification. HVs are regarded as one of the most practical types of environmentally friendly vehicle and have already been widely accepted in the market. Toyota Motor Corporation has positioned HV systems as a core technology that can be applied to all next-generation electrically powered environmentally friendly vehicles and is currently working to enhance the performance of HV system components. Because of its low loss and high-temperature operation properties, silicon carbide (SiC) is regarded as a highly promising material for power semiconductor devices to help reduce the size and weight of the power control unit, one of the key components of a HV system. Wide-ranging activities are under way to meet the challenges of adopting SiC in an automotive environment, such as the development of crystal growth technologies, device structures, process technologies, defect analysis, and application to on-board systems. This paper describes the current situation and future prospects for on-board SiC power devices and the development of SiC-based technologies.

Vector quantization based QoS evaluation in cognitive radio networks

In this paper, we characterize the QoS that secondary users can expect in a cognitive radio network in the presence of primaries. To that end, we first define a $$K$$K-dimensional QoS space where each point in that space characterizes the expected QoS. We show how the operating condition of the system maps to a point in the QoS space, the quality of which is given by the corresponding QoS index. To deal with the real-valued QoS space, we use vector quantization to partition the space into finite number of regions each of which is represented by one QoS index. We argue that any operating condition of the system can be mapped to one of the pre-computed QoS indices using a simple look-up in $$O(log\,N)$$O(logN) time--thus avoiding any cumbersome computation for QoS evaluation. The proposed technique takes the power vector as its input from the power control unit which we consider as a black box. Using simulations, we illustrate how a $$K$$K-dimensional QoS space can be constructed. We choose capacity as the QoS metrics and show what the expected capacity would be for a given power vector. We also show the effect of having large number of partitions on the distortion. As for the implementation feasibility of the proposed concept, we implement the QoS space on an 8-bit microcontroller and show how the mathematically intensive operations can be computed in a short time. Further we use binary search to achieve scalability as the dimensionality of the space increases.

Embedded Power Modules – A new approach using Power Core and High Power PCB

Power electronics packaging applications has strong demands regarding reliability and cost. The fields of developments reach from low power converter modules, over single or multichip MOSFET or IGBT packages, up to high power applications, like needed e.g. for solar inverters and automotive applications. This paper will give an overview about these applications and a description of each ones demand. The spectrum of conventional power electronics packaging reaches from SMD packages for power chips to large power modules. In most of these packages the power semiconductors are connected by bond wires, resulting in large resistances and parasitic inductance. Additionally bond wires result in a high stray inductance which limits the switching frequency. The embedding of chips using Printed Circuit Board (PCB) technology offers a solution for many of the problems in power packaging. This paper will show today's available power packages and power modules, realized in industrial production as well as in European research projects. All technologies which are used are based on PCB materials and processes. Chips are mounted to Cu foils, lead frames, high power PCBs or even ceramic substrates, embedded by vacuum lamination of laminate sheets and electrically connected by laser drilling and Cu plating. A new approach for embedded power modules will be presented in detail. In this project, different application fields are covered, ranging from 50 W over 500 W to 50kW power modules for different applications like single chip packages, over power control units for pedelec (Pedal Electric Cycle), to inverter modules for automotive applications. This approach will focus on a power core base structure for the embedded semiconductor, which is then connected to a high power PCB. The connection to the embedded die is realized by direct copper connection only. The technology principle will be described in detail. Frist manufactured demonstrators will be presented. The presented new approach for the realization of a power core structure offers new possibilities for the module manufacturing, avoiding soldering or Ag sintering of the power semiconductors and the handling of thick copper substrates during the embedding process.

Decentralized control of units in smart grids for the support of renewable energy supply

Due to the significant environmental impact of power production from fossil fuels and nuclear fission, future energy systems will increasingly rely on distributed and renewable energy sources (RES). The electrical feed-in from photovoltaic (PV) systems and wind energy converters (WEC) varies greatly both over short and long time periods (from minutes to seasons), and (not only) by this effect the supply of electrical power from RES and the demand for electrical power are not per se matching. In addition, with a growing share of generation capacity especially in distribution grids, the top-down paradigm of electricity distribution is gradually replaced by a bottom-up power supply. This altogether leads to new problems regarding the safe and reliable operation of power grids. In order to address these challenges, the notion of Smart Grids has been introduced. The inherent flexibilities, i.e. the set of feasible power schedules, of distributed power units have to be controlled in order to support demand–supply matching as well as stable grid operation. Controllable power units are e.g. combined heat and power plants, power storage systems such as batteries, and flexible power consumers such as heat pumps. By controlling the flexibilities of these units we are particularly able to optimize the local utilization of RES feed-in in a given power grid by integrating both supply and demand management measures with special respect to the electrical infrastructure. In this context, decentralized systems, autonomous agents and the concept of self-organizing systems will become key elements of the ICT based control of power units. In this contribution, we first show how a decentralized load management system for battery charging/discharging of electrical vehicles (EVs) can increase the locally used share of supply from PV systems in a low voltage grid. For a reliable demand side management of large sets of appliances, dynamic clustering of these appliances into uniformly controlled appliance sets is necessary. We introduce a method for self-organized clustering for this purpose and show how control of such clusters can affect load peaks in distribution grids. Subsequently, we give a short overview on how we are going to expand the idea of self-organized clusters of units into creating a virtual control center for dynamic virtual power plants (DVPP) offering products at a power market. For an efficient organization of DVPPs, the flexibilities of units have to be represented in a compact and easy to use manner. We give an introduction how the problem of representing a set of possibly 10100 feasible schedules can be solved by a machine-learning approach. In summary, this article provides an overall impression how we use agent based control techniques and methods of self-organization to support the further integration of distributed and renewable energy sources into power grids and energy markets.

Operational Performance of Synchronous Generator Hybrid-Excited by PMDC and PV Generators

In this paper, detailed operational performance of synchronous generator connected to infinite bus hybrid excited by Permanent-Magnet DC (PMDC) and Photovoltaic (PV) generators is presented. The PV generator is interfaced to the PMDC generator via DC-DC buck-boost switch mode converter which is used to control the voltage injected at all solar irradiance levels via adjusting its duty ratio. The PV generator is designed such that to meet the demands of the synchronous generator excitation at full solar irradiance. The PMDC generator is conventionally powered by fuel engine. Power control unit is used to automatically adjust the PMDC generator driving torque in order to compensate the power need once the output power from the PV generator decreases as a result of reduction in the solar irradiance. To have an idea about the stability of the system operating point, eigenvalues of the linearized system at different running conditions are discussed. The robustness of the system is checked by observing its response based on the complete nonlinear dynamical model after successive step changes in the solar irradiance levels and successive step changes in the set value of the desired excitation voltage particularly used for controlling both the terminal voltage and the output reactive power of the synchronous generator. It is concluded that the proposed hybrid excitation system is technically possible, reliable, can effectively control the output reactive power of the synchronous generator, reduces the total fuel consumption and robust enough to withstand step changes in the system input parameters.

Impedance compensated passive implantable atrial defibrillator

An impedance compensated passive implantable atrial defibrillator is reported. The two-part system consists of a handheld lithium-ion powered base unit (external power transmitter) and a passive (battery free) implantable coil (power receiver), with integrated rectifilter and power control unit, electrocardiogram (ECG) and bioimpedance measurement circuits, data communications circuitry and atrial connection leads. The system is designed to operate in two distinct modes: cardiac sense mode (wake-up, measure the impedance of the cardiac substrate and communicate data to the external base unit) and shock mode (delivery of an ECG synchronised impedance compensated monophasic very low tilt rectilinear shock waveform). A prototype was implemented and tested. In the sense mode, up to 5 W of sustained DC power was delivered across a 2.5 cm air–skin barrier with approximately 40% DC-to-DC power transfer efficiency at a transmission frequency of 185 kHz achieved, thereby providing 15.9 VDC (320 mA) to the implant side for measurement and communication at 433 MHz with the base unit. In the shock delivery mode, >186.9 W (rectilinear monophasic shock pulse: 100 V, 1.9 A, 12 ms duration) was repeatedly and reliably delivered transcutaneously to a 50 Ω cardiac load. Further testing in ten porcine models verified the in vivo operation, with inter-catheter impedance variations of ±20.1% measured between successive defibrillation attempts.