Smart Power Management Research Articles

Single-chip CMUT-on-CMOS front-end system for real-time volumetric IVUS and ICE imaging

Intravascular ultrasound (IVUS) and intracardiac echography (ICE) catheters with real-time volumetric ultrasound imaging capability can provide unique benefits to many interventional procedures used in the diagnosis and treatment of coronary and structural heart diseases. Integration of capacitive micromachined ultrasonic transducer (CMUT) arrays with front-end electronics in single-chip configuration allows for implementation of such catheter probes with reduced interconnect complexity, miniaturization, and high mechanical flexibility. We implemented a single-chip forward-looking (FL) ultrasound imaging system by fabricating a 1.4-mm-diameter dual-ring CMUT array using CMUT-on-CMOS technology on a front-end IC implemented in 0.35-μm CMOS process. The dual-ring array has 56 transmit elements and 48 receive elements on two separate concentric annular rings. The IC incorporates a 25-V pulser for each transmitter and a low-noise capacitive transimpedance amplifier (TIA) for each receiver, along with digital control and smart power management. The final shape of the silicon chip is a 1.5-mm-diameter donut with a 430-μm center hole for a guide wire. The overall front-end system requires only 13 external connections and provides 4 parallel RF outputs while consuming an average power of 20 mW. We measured RF A-scans from the integrated single- chip array which show full functionality at 20.1 MHz with 43% fractional bandwidth. We also tested and demonstrated the image quality of the system on a wire phantom and an ex vivo chicken heart sample. The measured axial and lateral point resolutions are 92 μm and 251 μm, respectively. We successfully acquired volumetric imaging data from the ex vivo chicken heart at 60 frames per second without any signal averaging. These demonstrative results indicate that single-chip CMUT-on-CMOS systems have the potential to produce realtime volumetric images with image quality and speed suitable for catheter-based clinical applications.

Modeling and Control Strategy of a Hybrid PV/Wind/Engine/Battery System to Provide Electricity and Drinkable Water for Remote Applications

In this paper a small-scale energy system called emergency container is presented. This container has lots of applications and can be designed as stationary solution in remote areas such as rural electrification and a mobile solution for disaster situation, military purposes and exploration teams. In this study the container is a hybrid PV/wind/engine energy system that is designed to provide electricity and drinkable water for 1000 person in disaster situations. A transient model implemented in Transient Simulation System (TRNSYS) program is developed and performance of the system during one-year operation for two locations (Nairobi in Kenya and Nyala in Sudan) with relatively high solar insolation is analyzed. The result of the model is significantly important in order to choose the right size of the different components. Due to the fluctuations of solar and wind energy as well as the importance of the battery life cycle, there is a need to have a smart power management and an appropriate fast response control system. In order to achieve it and to fulfill the energy demand as much as possible through renewable energies, a dispatch strategy is introduced and a control algorithm is applied to the model. This control algorithm has increased system reliability and power availability. The transient simulation shows that the share of power generation by solar energy is 63% and 80% and the share of wind power is 27% and 12% in Nairobi and Nyala respectively. It means that most of the energy demand (around 90%) can be covered by renewable energy. This results in significant mitigation of environmental issues compared to using only diesel engine that is a common solution in disaster situations.

Smart Power Management and Delay Reduction for Target Tracking in Wireless Sensor Networks

Energy efficiency and data transmission delay are critical issues for mobile target tracking wireless sensor networks, in which abundant sensor nodes are deployed to collect the target information from the sensing field. At present, many existing works have been concentrated on extending network lifetime, while less emphasis was placed on both transmission delay reduction and the adaptive sleep of sensor nodes considering the application constraints. In this paper, we propose a smart power management and delay reduction approach for target tracking based on a grid network structure, where sensor nodes adjust their sleep intervals according to the distance between the node and the moving target. Sensor nodes can distributedly decide their sleeping time using the information from their neighbors. Furthermore, we propose a real-time chain to relay the sensed data for transmission delay reduction. The proposed approach allows sensor nodes that are far away from the target to sleep more and make the target information forward to the sink in time. Experimental results verify that, in contrast to adaptive coordinate and local power management protocols, the proposed approach achieves a significant energy saving while maintaining a short transmission delay.

Priority based power sharing scheme for power consumption control in smart homes

 Abstract Efficient power consumption, intelligent power monitoring and interactive control of power consumption in smart homes are the key factors of sustainable development, reduction of power demand peaks and activities related to avoidance of blackout effects. The highlight of the proposed system is its ability to control maximum consuming power of the home appliances (HAs) and keep the total power consumption below a certain limit and allowing the home user more flexibility to operate their HAs based on HA priority. The proposed smart power management system consists of smart electric sensors (SESs) and power provisioning controller (PPC). The PPC and SES are concurrently used to control and maintain stability and complete power waveform behavior examination. However, we need to reassign an amount of consuming power from one HA to another when the ON/OFF status of HA changes. This paper offers a system to control the maximum power consumption considering heterogeneous HAs with different response speed. In order to guarantee the maximum consuming power limit, we compute the limited suggested power level for HAs. Simulation results show the effectiveness of our system in managing maximum power consumption.

Stability Analysis for Smart Homes Energy Management System with Delay Consideration

There is a tendency to consume electrical energy simultaneously by home appliances (HAs) leading to frequent demand peaks. Nowadays the number of (HAs) in modern residences has significantly increased as compared to the past. If the power demand is not met with the limited available power supply, this could lead to major power blackout. Our smart power management system consists of smart electric sensor (SES) and power provisioning controller (PPC). The PPC and SES are used to control and maintain stability with complete power waveform behavior examination. In this paper, we focus on achieving optimal system model for smart homes to reduce the risks of power blackout by applying two different criteria of power assignment for the HAs. A comparative study has been conducted which show the drastic change in the system behavior by changing the power assignment criteria. We also carry out the stability analysis for the proposed system model of smart homes. The stability analysis verifies that the system stability is dependent on some time delay. Simulation results also help us to observe critical system behaviors such as stability and overshoot of energy waveform.

Wireless Architectures for Heterogeneous Sensing in Smart Home Applications: Concepts and Real Implementation

Application of wireless technologies in the smart home is dealt with by pointing out advantages and limitations of available approaches for the solution of heterogeneous and coexisting problems related to the distributed monitoring of the home and the inhabitants. Some hot challenges facing the exploitation of noninvasive wireless devices for user behavior monitoring are then addressed and the application fields of smart power management and elderly people monitoring are chosen as representative cases where the estimation of user activities improves the potential of location-aware services in the smart home. The problem of user localization is considered with great care to minimize the invasiveness of the monitoring system. Wireless architectures are reviewed and discussed as flexible and transparent tools toward the paradigm of a totally automatic/autonomic environment. With respect to available state-of-the-art solutions, our proposed architecture is based also on existing wireless devices and exploits, in an opportunistic way, the characteristics of wireless signals to estimate the presence, the movements, and the behaviors of inhabitants, reducing the system complexity and costs. Selected and representative examples from real implementations are presented to give some insight on state-of-the-art solutions also envisaging possible future trends.

The Residential Intelligent Power Consumption Management System

Because of lacking of effective management and various energy-saving measures, a family smart power management system is introduced. The system includes the servers, LAN and smart power management terminal; the system can control the equipment to achieve the scientific management, and provide users a platform to interact with electrical equipment; the user can use the phone , PAD, PC and other mobile devices log the specified smart power management service website anytime, anywhere to control the electrical household electrical household appliances and query the power consumption, also can control the electrical household electrical household appliances at home through the smart power management terminal. According to the test of the system, the performances verify the system can effectively improve the power consumption rate, and achieve a good energy saving effect.

Smart DC Power Management System Based on Software-Configurable Power Modules

DC bus-based systems are envisioned as an enabling technology to integrate renewable energy sources, energy storage devices, and a variety of loads in a number of power management and distribution scenarios. The system design and integration challenges include accommodating heterogeneous components, the wide variability of operating conditions, and system stability issues arising from dynamical interactions between the components. This paper proposes a flexible, smart dc power management architecture based on identical digitally controlled bidirectional dc–dc modules that can be software configured to enable simple system design, exceptional system flexibility, and optimization of the use of available resources. Design of the reconfigurable digital control infrastructure of such versatile dc power system is discussed in detail from its system-level description to the low-level design of the digital compensators. Stability analysis of the dc bus voltage is also discussed, proving the robustness of the power architecture from a theoretical standpoint. The proposed approach is then demonstrated on an experimental dc power management system consisting of several 500 W, bidirectional dc–dc modules operating from a 24-V dc bus.

Variable Priority Number Control of SPMS for Leisure Ship

The power system of leisure ship has a character of stand-alone type, so it continuously checks the usable power. Especially, the leisure ship using renewable energy needs to adjust the power consumption of loads according to the usable power. Also, the important loads of leisure ship are different by operation mode. However, current power management system doesnot consider such character. This paper studied load management system of the SPMS(Smart Power Management System) and composed using the smart plug. The SPMS controls the loads depending on a user’s pattern and character through variable priority number control. This control algorithm was verified through simulation of assumed user and situation using LabVIEW.

Smart Power Management System for Leisure-ship

A leisure ship has a stand-alone type power system, and a generator is in use on this condition. But the generator cannot be operated in condition of leisure activity, ocean measurement and etc, because of environment and noise. Recently, renewable energy system is connected with power system of the leisure-ship for saving energy. The renewable energy system can not supply the stable power to leisure-ship because power generation changes according to weather condition. And most of the leisure ship is operated without methodical power management system. This study's purpose is to develop SPMS(Smart Power Management System) algorithm using the renewable energy (photovoltaic, wind power and etc.). The proposed algorithm is able to supply stable the power according to operation mode. Furthermore, the SPMS manages electric load (sailing and communication equipment, TV, fan, etc.) and reduces operating times of the generator. In this paper, the proposed algorithm is realized and executed by using LabVIEW. As a result, the hour for operating the generator is minimized.

Smart power management for mobile handsets

Mobile terminals are rapidly evolving from enhanced phones to powerful platforms capable of offering a multitude of services and critical applications. They have a small form factor and are typically equipped with powerful processors, a large display, a high-resolution camera, and specialized sensors. The hardware has to simultaneously support applications that have varying run-times and varying communication and computation requirements. As a consequence, power-intensive applications can easily drain the battery and leave the mobile terminal useless in no time. In this paper, we develop concepts for advanced power-aware task management. A power-aware task monitor in the mobile terminal keeps track of the battery state, the communication channel, and the processor(s). It takes the application profile, channel quality, anticipated duration, and other factors into account to determine the required resources and the impact on the battery life, and it also updates the battery and application profiles. A power-aware task scheduler in the mobile terminal uses information provided by the power-aware task monitor to determine whether or not to execute applications. It can reserve power for critical services such as emergency calls, authentication, and payment and banking applications. Network-based power management and application-based power management can be achieved for mobile terminals when information about the handset's battery power and application profile is communicated to the network. A network-based power manager can help determine when and how to support power-intensive applications, and may provide the handset with location-based coverage information and adjust the communication strategy to reduce the power required for communication and processing in the handset. A power manager in the application server can help to minimize power consumption by adjusting the flow and the contents communicated to the mobile terminal.

Powering down

Smart power management is all about doing more with the resources we have.

Optimizing the hot carrier reliability of N-LDMOS transistor arrays

Smart power management applications often require operation in the 20–30 V range. These applications combine a high performance BiCMOS process with a power lateral DMOS (LDMOS) driver. To obtain high drive current density and minimal on-resistance ( R dson), LDMOS devices are implemented in transistor arrays. Because of the high voltages and currents applied to these devices hot carrier degradation is a real reliability concern. This paper discusses several aspects of N-LDMOS hot carrier reliability including measurement techniques, degradation mechanism, and the effect of both one-dimensional (1-D) and two-dimensional (2-D) layout effects on the hot carrier degradation behavior of these devices. This paper focuses on device layout optimization rather than process changes since layout optimization has the advantage of improving performance without impacting other supported devices.

On the optimization of ultra low power front-end interfaces for capacitive sensors

Traditionally, most of the sensor interfaces must be tailored towards a specific application. This design approach is inflexible and requires several iteration steps for new sensor applications. It usually results in high costs for low and medium quantity market products. On the other hand, generic interface design reduces the costs and may provide a handy solution for multisensor applications. This paper presents a new generic architecture for ultra low power (ULP) capacitive sensor systems. It consists of a sensor interface followed by a modulator. The sensor interface (capacitance to voltage converters and switched capacitor (SC) amplifier) works on a lower clock frequency, 8 kHz, than the modulator, 128 kHz, to achieve very low power consumption. A new capacitance to voltage converter with class AB and correlated double sampling (CDS) operation reduces the shunt conductance leakage. The system maintains a smart power management by adapting biasing currents, measurement time and duty cycle according to the needs of the application (parasitic element reduction, accuracy and speed). The proposed architecture provides an interface to a broad range of capacitive sensors. The simulations show that the readout circuitry consumes merely 29 μA in operational mode with a 3 V power supply.

C-MEMS for the Manufacture of 3D Microbatteries

We have demonstrated that carbon-microelectromechanical systems (C-MEMS), in which patterned photoresist is pyrolyzed in inert environment at high temperature, constitutes a powerful approach to building 3D carbon microelectrode arrays for 3D microbattery applications. High aspect ratio carbon posts (>10:1) are achieved by pyrolyzing SU-8 negative photoresist in a simple one step process. Lithium can be reversibly charged and discharged into these C-MEMS electrodes. Because of the additional volume of the posts, higher capacities are achieved with the 3D array electrodes as compared to unpatterned carbon films with the same projected electrode area. These novel electrode arrays represent one of the critical components for 3D batteries, which may be interconnected with C-MEMS leads to enable smart power management schemes.