Copy of Transient Stability Testing of Transmission Line Fed LED Driver - on Tue, 03/24/2020 - 11:15 Designer230409 × Member for 5 years 0 designs 1 groups Add a bio to your profile to share information about yourself with other SystemVision users. https://explore.partquest.com/node/287729 <iframe allowfullscreen="true" referrerpolicy="origin-when-cross-origin" frameborder="0" width="100%" height="720" scrolling="no" src="https://explore.partquest.com/node/287729"></iframe> Title Description <p>This is a companion example to the design: "TDFS Impedance Stability of Transmission Line Fed LED Driver - Switching". In this version, a switch is added to turn on two of the LEDs after 2 ms, to inject a load transient into the system. This transient will expose the severity of the damped ringing response at the converter input, or system instability if the source/load impedance ratio is inadequate.</p> <p>The initial configuration for this design uses a cable length of 400 meters with 8 AWG = 2.1 mOhm/meter conductors, and a converter input capacitor = 22uF. This is consistent with the companion design. You can try using an increased cable length (e.g. 800 meters, 5 AWG = 1 mOhm/meter) by making a copy of this design and re-running the simulation. You will see that the circuit becomes unstable at that longer length. You can also try larger values of input capacitance, to mitigate the instability problem.</p> About text formats Tags Buck ConverterConstant Power LoadsSwitching ConverterLEDtransmission lineStep-DownTDFS Impedance Stability Select a tag from the list or create your own.Drag to re-order taxonomy terms. License - None -
Copy of Transient Stability Testing of Transmission Line Fed LED Driver - on Tue, 03/24/2020 - 11:15 Designer230409 × Member for 5 years 0 designs 1 groups Add a bio to your profile to share information about yourself with other SystemVision users. https://explore.partquest.com/node/287729 <iframe allowfullscreen="true" referrerpolicy="origin-when-cross-origin" frameborder="0" width="100%" height="720" scrolling="no" src="https://explore.partquest.com/node/287729"></iframe> Title Description <p>This is a companion example to the design: "TDFS Impedance Stability of Transmission Line Fed LED Driver - Switching". In this version, a switch is added to turn on two of the LEDs after 2 ms, to inject a load transient into the system. This transient will expose the severity of the damped ringing response at the converter input, or system instability if the source/load impedance ratio is inadequate.</p> <p>The initial configuration for this design uses a cable length of 400 meters with 8 AWG = 2.1 mOhm/meter conductors, and a converter input capacitor = 22uF. This is consistent with the companion design. You can try using an increased cable length (e.g. 800 meters, 5 AWG = 1 mOhm/meter) by making a copy of this design and re-running the simulation. You will see that the circuit becomes unstable at that longer length. You can also try larger values of input capacitance, to mitigate the instability problem.</p> About text formats Tags Buck ConverterConstant Power LoadsSwitching ConverterLEDtransmission lineStep-DownTDFS Impedance Stability Select a tag from the list or create your own.Drag to re-order taxonomy terms. License - None -
Copy of Transient Stability Testing of Transmission Line Fed LED Driver - on Thu, 03/12/2020 - 07:50 Designer230175 × Member for 5 years 1 designs 1 groups Add a bio to your profile to share information about yourself with other SystemVision users. https://explore.partquest.com/node/285979 <iframe allowfullscreen="true" referrerpolicy="origin-when-cross-origin" frameborder="0" width="100%" height="720" scrolling="no" src="https://explore.partquest.com/node/285979"></iframe> Title Description <p>This is a companion example to the design: "TDFS Impedance Stability of Transmission Line Fed LED Driver - Switching". In this version, a switch is added to turn on two of the LEDs after 2 ms, to inject a load transient into the system. This transient will expose the severity of the damped ringing response at the converter input, or system instability if the source/load impedance ratio is inadequate.</p> <p>The initial configuration for this design uses a cable length of 400 meters with 8 AWG = 2.1 mOhm/meter conductors, and a converter input capacitor = 22uF. This is consistent with the companion design. You can try using an increased cable length (e.g. 800 meters, 5 AWG = 1 mOhm/meter) by making a copy of this design and re-running the simulation. You will see that the circuit becomes unstable at that longer length. You can also try larger values of input capacitance, to mitigate the instability problem.</p> About text formats Tags Buck ConverterConstant Power LoadsSwitching ConverterLEDtransmission lineStep-DownTDFS Impedance Stability Select a tag from the list or create your own.Drag to re-order taxonomy terms. License - None -
Copy of Transient Stability Testing of Transmission Line Fed LED Driver - on Wed, 03/04/2020 - 09:55 Designer71746 × Member for 8 years 6 months 7 designs 1 groups Add a bio to your profile to share information about yourself with other SystemVision users. https://explore.partquest.com/node/285073 <iframe allowfullscreen="true" referrerpolicy="origin-when-cross-origin" frameborder="0" width="100%" height="720" scrolling="no" src="https://explore.partquest.com/node/285073"></iframe> Title Description <p>Este es un ejemplo complementario del diseño: "Estabilidad de impedancia TDFS del controlador LED alimentado por línea de transmisión - Conmutación". En esta versión, se agrega un interruptor para encender dos de los LED después de 2 ms, para inyectar una carga transitoria en el sistema. Este transitorio expondrá la gravedad de la respuesta de llamada amortiguada en la entrada del convertidor o la inestabilidad del sistema si la relación fuente / impedancia de carga es inadecuada.</p> <p>La configuración inicial para este diseño utiliza una longitud de cable de 400 metros con 8 AWG = 2.1 mOhm / metro conductores y un condensador de entrada del convertidor = 22uF. Esto es consistente con el diseño complementario. Puede intentar usar un cable de mayor longitud (por ejemplo, 800 metros, 5 AWG = 1 mOhm / metro) haciendo una copia de este diseño y volviendo a ejecutar la simulación. Verá que el circuito se vuelve inestable en esa longitud más larga. También puede probar valores más grandes de capacitancia de entrada para mitigar el problema de inestabilidad.</p> About text formats Tags Buck ConverterConstant Power LoadsSwitching ConverterLEDtransmission lineStep-DownTDFS Impedance Stability Select a tag from the list or create your own.Drag to re-order taxonomy terms. License - None -
Buck Converter PWM Modulator Line Transient Demo Designer43361 × Member for 8 years 11 months 328 designs 2 groups https://explore.partquest.com/node/268620 <iframe allowfullscreen="true" referrerpolicy="origin-when-cross-origin" frameborder="0" width="100%" height="720" scrolling="no" src="https://explore.partquest.com/node/268620"></iframe> Title Description <p>Here's my attempt to model the PWM modulator in the frequency domain. It's a buck converterr switching at 200KHz. I use the advanced options to specify a linear frequency sweep, which includes harmonics of the switching frequency. There's a line frequency disturbance that modulates steady state response. Please note that my modulator model is only valid for voltage mode control.</p> <p>The line voltage is disturbed by bursts of pulses. The disturbance passes through to the output voltage. You can select different frequency ranges by adding and removing Spice comment indicators in the simulation controls.</p> <p>Compare results to Mike's TDFS analysis.</p> <p>This version is under test to determine its accuracy and faithfulness to the actual switching characteristics.</p> <p>[1] See Vorperian's "Simplified Analysis of PWM Converters Using Model of PWM Switch Part 1" in the May 1990 issue (Vol. 26, No. 3) of the IEEE Transactions on Aerospace and Electronic Systems.</p> About text formats Tags Buck ConverterSwitching ConverterStep-DownSpectral Source QuantitiesEMI Select a tag from the list or create your own.Drag to re-order taxonomy terms. License - None -
TDFS Loop Stability for Step-Down DC to DC (Buck) Converter - Switching https://explore.partquest.com/node/128196 <iframe allowfullscreen="true" referrerpolicy="origin-when-cross-origin" frameborder="0" width="100%" height="720" scrolling="no" src="https://explore.partquest.com/node/128196"></iframe> Title Description <p>This example demonstrates the TDFS (Time Domain Frequency Sweep) Loop Stability Instrument Model. It is used to compute the open-loop transfer function of an operating (closed-loop) switching power converter. There is no need for state-average or continuous equivalent models for the modulator section of the design, as normally needed for frequency-domain (or "AC") analysis. Rather, the actual circuit component models can be used directly, because the open-loop transfer function is computed from time-domain simulation results.</p><p>In this case, the converter is operating at 200kHz switching frequency, and is converting the 12V DC input to a regulated 5V output, while supplying a 5A current to the 1 Ohm load resistor. The TDFS measurement instrument indicates that the open-loop gain crossover frequency is at 26 kHz, and the phase margin is just under 60 degrees. This verifies that the opamp-based lead-lag compensator is providing adequate stability margin under these operating conditions.</p><p>Note that the TDFS instrument model characterizes the open loop transfer function by injecting a small sinusoidal stimulus signal in series with the loop, and then measures the complex ratio of the return signal to the injected signal, is described in:</p><p>D. Venable, “Testing Power Sources for Stability”, Venable technical paper #1, Venable Industries.</p><p>The companion example, "Step-Down (Buck) DC to DC Converter - Switching", shows the line and load transient response of this converter design. Another companion example, "Step-Down (Buck) DC to DC Converter - Continuous", uses a state-average model of the switching (or modulator) section of the converter, so it supports traditional "AC" or frequency-domain analysis.</p> About text formats Tags Buck ConverterOp-Amp Lead-Lag CompensatorSwitching ConverterPEG127KA3110Q Electrolytic CapacitorMC33272A OP-AMPXAL6060-223 InductorNRVTS560EMFS Schottky Power RectifierStep-Down Select a tag from the list or create your own.Drag to re-order taxonomy terms. License - None -
