Week #10: Discussion results Further research on our ideas Group #33 Group member: Tianhao Han Ximeng Sun(Susie) Xing Cao(Star) Zhuoran Yang RAID Redundant Array of Independent Disks A storage technology that combines multiple disk drive components into a logical unit. It used frequently on servers but aren't generally necessary for personal computers. RAID It allows you to store the same data in multiple paces in a balanced way to improve overall storage performance. Data is distributed across the drives in one of several ways called "RAID levels”. RAID Controller Batteries Why we need RAID batteries? How does a RAID battery work? Types of RAID battery. Why we need RAID batteries? It allows the raid card to remember what is in its buffers. An UPS is not safe enough. How does a RAID battery work? The battery is fully discharged at first. Once the server is powered, the battery begins a full charge cycle. On most controllers, it takes three hours to fully charge the battery. The controller can be used during this time; however, the battery is unable to meet the specified holdover time until it is fully charged. The battery is still able to handle brief power losses during the initial charge cycle. How does a RAID battery work? The battery is designed to provide a minimum of 72 hours protection for DIMMs up to 64 MB and 48 hours protection for 128-MB DIMMs. Types of RAID battery NiMHi batteries NiMHi batteries require that you run the battery recondition task every six months to maintain reliability. A battery recondition fully discharges and then recharges the battery. When the battery needs reconditioning, the controller reports its state as Degraded or Low Charge. Types of RAID battery Li-Ion batteries The Li-Ion or lithium ion batteries are automatically reconditioned by the controller.These batteries do not require that you run the battery recondition task. Types of RAID battery All RAID controller batteries should be replaced every three years. Ideas Use fuel gauge chip, battery charge management chip and LED to show how long does this RAID battery can be used. Combining solar energy to RAID battery, so that the RAID battery can provide a long time protection . Kinetic Energy Recovery System KERS What is KERS? KERS is an automotive system for recovering a moving vehicle's kinetic energy under braking. The recovered energy is stored in a reservoir(such as a battery or flywheel) for later use under acceleration. KERS Motor and electrical generator KERS button KERS Motor generator unit Battery management system Two kinds of KERS 1:Store the energy to flywheel 2:Store the energy to battery Why Flywheel? Can store more energy than a battery for its weight. Can be charge/discharge very quickly. Why Battery? Cheap than flywheel. Flexible Mature technology Why we choose second choice Battery: 1: Can build in any shape. So we don’t need to redesign the transmission. 2: Cheap, less money than the flywheel. Why we use this system? European emission standards: 2007: CO2 emission 160g/km ↓↓ 2012:CO2 emission 120g/km Seems Hybird passenger vehicle will have a big market. Ultra Low Power Boost Converter with Battery Management for Energy Harvester Applications ----------------BQ25504 Feature Ultra Low Power With High Efficiency DC/DC Battery Status Output Programmable Dynamic Maximum Power Point Tracking (MPPT) Energy Storage Battery Charging and Protection Boost Converter/Charger Applications Energy Harvesting Solar Charger Thermal Electric Generator (TEG) Harvesting Wireless Sensor Networks (WSN) Industrial Monitoring Environmental Monitoring Bridge and Structural Health Monitoring (SHM) Smart Building Controls Portable and Wearable Health Devices Entertainment System Remote Controls Description The bq25504 is the first of a new family of intelligent integrated energy harvesting Nano-Power management solutions that are well suited for meeting the special needs of ultra low power applications. The product is specifically designed to efficiently acquire and manage the microwatts (μW) to miliwatts (mW) of power generated from a variety of DC sources like photovoltaic (solar) or thermal electric generators. The bq25504 is the first device of its kind to implement a highly efficient boost converter/charger targeted toward products and systems, such as wireless sensor networks (WSN) which have stringent power and operational demands. Description The design of the bq25504 starts with a DCDC boost converter/charger that requires only microwatts of power to begin operating. Once started, the boost converter/charger can effectively extract power from low voltage output harvesters such as thermoelectric generators (TEGs) or single or dual cell solar panels. The boost converter can be started with VIN as low as 330 mV, and once started, can continue to harvest energy down to VIN = 80 mV. Description The bq25504 also implements a programmable maximum power point tracking sampling network to optimize the transfer of power into the device. Sampling the VIN_DC open circuit voltage is programmed using external resistors, and held with an external capacitor (CREF). The bq25504 was designed with the flexibility to support a variety of energy storage elements. The availability of the sources from which harvesters extract their energy can often be sporadic or time-varying. Systems will typically need some type of energy storage element, such as a re-chargeable battery, super capacitor, or conventional capacitor. The storage element will make certain constant power is available when needed for the systems. The storage element also allows the system to handle any peak currents that can not directly come from the input source. Related End Equipment Parametric bq25504 3mm x 3mm QFN16 Package Typical Solar Application Circuit Typical TEG Application Circuit HIGH-LEVEL FUNCTIONAL BLOCK DIAGRAM Wireless charging Electromagnetic induction Magnetic Resonant Inductive Power Transmission A transmitter coil L1/A receiver coil L2 An alternating current in the transmitter coil generates a magnetic field which induces a voltage in the receiver coil. The efficiency of the power transfer depneds on the coupling(k) The coupling is determined by the distance between the inductors (z) and the relative size (D2 /D). The coupling is further determined by the shape of the coils and the angle between them (not shown). Efficiency of Inductive power transmission The values are shown as a function of the axial distance of the coils (z/D). The parameter is the diameter of the smaller coil D2. The efficiency drops dramatically at larger distance (z/D > 1) or at a large size difference of the coil (D2/D < 0.3) A high efficiency (>90%) can be achieved at close distance (z/D < 0.1) and for coils of similar size (D2/D = 0.5..1) Resonant Magnetic Coupling Magnetic coupling occurs when two objects exchange energy through their varying or oscillating magnetic fields. Resonant coupling occurs when the natural frequencies of the two objects are approximately the same. The yellow shows two idealized resonant magnetic coils. The blue and red color bands illustrate their magnetic fields. The coupling of their respective magnetic fields is indicated by the connection of the colorbands. Special designed magnetic resonators “power sources & capture”(efficiently transfer power over large distances) • • • • • High Efficiency Over Distance Penetrates and Wraps-Around Obstacles Safe for people and animals From milliwatts to kilowatts Devices that can fit into OEM products And so on…… Disadvantage for Involving Good products(Powermat, Witricity and so on ) Weak background(Qualcomm, Wireless Power Consortium(WPC), Witricity) No convenience enough(what we image is looking like Wifi) Less room for device and increasing technology for battery(maybe using the big capacity battery) More standard(at least 6) and difficult to spread Be replacing by other battery(Li-air battery) Question time. Thank you for your listening!