A duty cycle generator for switching regulators.
Duty cycle IC generator for switching regulators, discussing construction, resistive and dielectric films fabrication, applications, etc
Gutknecht, P.↗
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Optimal flash rate and duty cycle for flashing visual indicators.
This experiment examined the ability of observers to determine, as quickly as possible, whether a visual indicator was steadily on or flashing. Six flash rates (periods) were combined factorially with three duty cycles (on-off ratios) to define 18 ?types' of intermittent signals. Experimental sessions were divided into six runs of 100 trials, each run utilizing one of the six flash rates. On any given trial in a run, the probability of a steady signal occurring was 0.5 and the probability of a flashing signal occurring was 0.5. A different duty cycle was employed daily for each experimental session. In all, 400 trials were devoted to each of the flash rates at each duty cycle. Accuracy and latency of response were the dependent variables of interest. The results show that the observers view the light for an interval of time appropriate to the expected flash rate and duty cycle; whether they judge the light to be steady or intermittent depends upon whether the light is extinguished during the predetermined waiting period. Adoption of this temporal criterion delays responding in comparison to those tasks involving responses to light onset. The decision or response criteria held by the observers are also sensitive to the parameters of the flashing light: observers become increasingly willing to call a flashing light ?steady' as flash duration increases.
Markowitz, J.↗
Medium- and Heavy-Duty Truck Duty Cycles
This dataset provides second-by-second duty cycle data for Class 6 and Class 8 diesel trucks in Texas, including key vehicle metrics, engine-related data, and GPS data (excluding GPS latitude and longitude to ensure confidentiality). The data were collected via tablets installed on the trucks and organized into daily datasets, each associated with a unique vehicle ID and date. There are 12 daily datasets for Class 6 diesel trucks (three unique vehicle IDs) and 43 daily datasets for Class 8 diesel trucks (six unique vehicle IDs). The units associated with each column are included in the name. The engine performance data include columns such as engine speed, engine percent torque, and engine fuel rate. Road grade (%/100) was estimated using the GPS altitude and wheel-based vehicle speed, which is used as an input for FASTSim. Cumulative distance was also calculated using the wheel-based vehicle speed. Additional columns include: - Engine Speed (RPM): Removed inaccurate readings and used to calculate angular velocity (radians/second). - Torque (N·m): Calculated using engine percent torque, nominal friction percent torque, and engine reference torque values (those columns were removed from dataset), then normalized to express as torque (%). - Flywheel Power (%): Calculated using the angular velocity and torque (in kW), then normalized as a percentage of the maximum value. - Engine Fuel Rate (%) and Torque (%): Both metrics were normalized by dividing by their respective maximum values within each dataset to express them as percentages. The datasets were analyzed to assess the energy impact of various driving behaviors, simulate energy efficiency, and recommend optimal routes for diesel trucks using NLR’s tool called RouteE. For driver coaching, factors like speed and acceleration limits were considered, and idle periods were reduced (assuming the engine was off during idling) to adjust each drive cycle. These adjusted drive cycles were then simulated in FASTSim to evaluate their effect on fleet energy consumption and estimate potential energy savings. The original cycles are available for download on this page 
1Hz↗
Design and fabrication of an analog voltage to duty cycle generator Interim progress report
Design and fabrication of analog voltage to duty cycle generator
ANALOG-TO-DIGITAL CONVERTER↗
Constant-frequency, variable-duty-cycle multivibrator
Circuit provides a pulse source of constant frequency with a duty cycle that is adjustable by an external input signal. It could serve as a switching mode voltage regulator or as a switching source for control systems.
Johnson, J. E.↗
Analog voltage to duty cycle generator First quarterly progress report
System feasibility testing of analog voltage to duty cycle generator, and production process for thin film tantalum resistors
THIN FILM↗
Analog voltage to duty cycle generator Second quarterly progress report
System function tests on analog voltage to duty cycle generator with hybrid microelectronic circuitry
MICROELECTRONICS↗
Design and fabrication of an analog voltage to duty cycle generator Interim progress report Oct. - Dec. 1966
Integrated circuit design for analog voltage to duty cycle generator
GENERATOR↗
Design and fabrication of an analog voltage to duty cycle generator Interim progress report
Circuit design, fabrication, and packaging work on analog voltage to duty cycle generator
Source record↗
DC to DC converter regulated by a constant- frequency duty-cycle generator.
Closed loop regulated flyback DC to DC converter using constant frequency generator for duty cycle control
Babaa, I. M. H.↗
The Real Inputs Behind TCO: Duty Cycle Realism and Opportunity Costs using T3CO
NLR's Transportation Technology Total Cost of Ownership (T3CO) model provides realistic and robust analysis, capturing the impact of real world duty cycles and their variability in operating and opportunity costs. Case studies show that these contributions to costs can be significant and can alter conclusions about technology cost effectiveness.
33 ADVANCED PROPULSION SYSTEMS↗
ASDTIC duty-cycle control for power converters
The application of analog signal to discrete interval converter (ASDTIC), a hybrid micromodule, two loop control subsystem, to a switching, stepdown dc to dc converter is described. The power circuitry, interface and ASDTIC subsystems used in this switching regulator were developed to exhibit the improved regulation, transient performance, regulator stability and freedom from the effects of variations in parts characteristics due to environmental changes and aging. ASDTIC can be used with other types of power circuits that use duty-cycle control techniques by simple changes in the interface subsystem. The circuitry and performance characteristics of a +10V dc switching converter as well as that of the ASDTIC micromodule are described. Realization of the ASDTIC hybrid micromodule has been accomplished with a hermetically sealed, beam-lead, bonded/deposited nichrome thin film resistors, discrete capacitors and integrated circuits on dilithic, glazed alumina substrates using 22 feed through terminals in an integrated package.
Lalli, V. R.↗
CRADA Final Report: Ultralong Cycle Life and Ultrafast Charging Batteries to Electrify High Duty-Cycle, Mobile Platforms
As part of the Cyclotron Road program, Tyfast Energy Corp. aimed to investigate the Li 3 V 2 O 5 (LVO) anode material for next generation lithium batteries. State of the art and fast charging lithium-ion batteries are based on the lithium titanate or Li 4 Ti 5 O 12 (LTO) anode chemistry. LTO cells demonstrate fast charging times (<6 mins), long cycle life (>20,000 cycles), but at the expense of very low energy density (<200Wh/L, <80Wh/kg). Silicon anodes have the promise of achieving fast charging times, however, issues with cycling stability in combination with fast charging is unknown. LVO has unique properties that enable new performance window for lithium batteries. First, LVO operates at an average potential of 0.6V vs. Li/Li + , well above the Li-metal plating region allowing ultrafast charge capability without sacrificing safety. Second, the LVO has a high specific capacity of 250 mAh/g making battery pack energy density equivalent with current high-energy Li-ion chemistries.
25 ENERGY STORAGE↗
Design and fabrication of an analog voltage to duty cycle generator Final report
Analog voltage to duty generator design and fabrication based on four silicon integrated circuit chips in single package assembly
Source record↗
ASDTIC duty-cycle control for power converters.
The application of analog signal to discrete interval converter (ASDTIC), a hybrid micromodule, two-loop control subsystem, to a switching, stepdown dc-to-dc converter is described. The power circuitry, interface and ASDTIC subsystems used in this switching regulator were developed to exhibit the improved regulation, transient performance, regulator stability, and freedom from the effects of variations in parts characteristics due to environmental changes and aging. The circuitry and performance characteristics of a +10-V dc switching converter as well as that of the ASDTIC micromodule are described. Realization of the ASDTIC hybrid micromodule has been accomplished with hermetically sealed, beam-lead, bonded/deposited nichrome thin film resistors, discrete capacitors, and integrated circuits on dilithic, glazed alumina substrates, using 22 feed through terminals in an integrated package.
Lalli, V. R.↗
Mariner Jupiter/Saturn LCSSE thruster/valve assembly and injection propulsion unit rocket engine assemblies: 0.2-lbf T/VA development and margin limit test report
Thruster valve assemblies (T/VA's) were subjected to the development test program for the combined JPL Low-Cost Standardized Spacecraft Equipment (LCSSE) and Mariner Jupiter/Saturn '77 spacecraft (MJS) programs. The development test program was designed to achieve the following program goals: (1) demonstrate T/VA design compliance with JPL Specifications, (2) to conduct a complete performance Cf map of the T/VA over the full operating range of environment, (3) demonstrate T/VA life capability and characteristics of life margin for steady-state limit cycle and momentum wheel desaturation duty cycles, (4) verification of structural design capability, and (5) generate a computerized performance model capable of predicting T/VA operation over pressures ranging from 420 to 70 psia, propellant temperatures ranging from 140 F to 40 F, pulse widths of 0.008 to steady-state operation with unlimited duty cycle capability, and finally predict the transient performance associated with reactor heatup during any given duty cycle, start temperature, feed pressure, and propellant temperature conditions.
Clark, E. C.↗
EV Shuttle Bus Pilot
The EV Shuttle Bus Pilot dataset contains data and analysis from Hocking-Athens-Perry Community Action's demonstration of an electric bus on routes of their rural Athens Public Transit system. The vehicle used in the demonstration was a Ford E-450 cutaway equipped with an electric drivetrain, a 127-kWh battery system by Motiv Power Systems, and a cabin upfit by Turtle Top. Data gathered include route assignments, running time and distance, fuel economy, and charge cycles. A comparison of the vehicle's observed duty cycle with duty cycle modeling from other rural transit fleets in the National Transit Database is included to help better understand the rural adoption potential for this fleet technology.
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
Controllers for Battery Chargers and Battery Chargers Therefrom
A controller for a battery charger that includes a power converter has parametric sensors for providing a sensed Vin signal, a sensed Vout signal and a sensed Iout signal. A battery current regulator (BCR) is coupled to receive the sensed Iout signal and an Iout reference, and outputs a first duty cycle control signal. An input voltage regulator (IVR) receives the sensed Vin signal and a Vin reference. The IVR provides a second duty cycle control signal. A processor receives the sensed Iout signal and utilizes a Maximum Power Point Tracking (MPPT) algorithm, and provides the Vin reference to the IVR. A selection block forwards one of the first and second duty cycle control signals as a duty cycle control signal to the power converter. Dynamic switching between the first and second duty cycle control signals maximizes the power delivered to the battery.
Elmes, John↗