Switching strategies for power electronic converters

Explore gating signals for power devices, starting with a single switch buck converter. Learn pulse width modulation, its link to amplitude and frequency modulation, and Python based frequency analysis.

Apply pulse width modulation to gate power devices in converters, and understand modulation concepts—modulation signal, carrier signal, and demodulation—through a communications perspective for clearer power electronics.

Explore modulation by using a cosine modulation signal on a cosine carrier, yielding a modulated output and highlighting amplitude modulation and frequency modulation.

Explore amplitude modulation, where the modulated signal's amplitude depends on the modulation signal and a carrier; multiplying yields sum and difference frequencies with a high-frequency carrier and a low-frequency envelope.

Prepare your simulation workflow by using Anaconda to create isolated Python environments, manage Python versions (3.x), and install required packages for power electronics simulations.

Explore NumPy and matplotlib resources to plot waveforms and frequency responses for power electronics, with guidance on installation in the Anaconda environment and accessing comprehensive documentation.

learn to install numpy and matplotlib in a conda environment, activate esp, manage dependencies and occasional network retries, and prepare for data science work with these tools.

Explore amplitude modulation in a Python project for switching strategies in power electronics, using numpy, matplotlib, and Visual Studio Code, with time arrays and plots.

Explore how to simulate amplitude modulation by multiplying a modulation cosine with a high-frequency carrier, plot the signals with Matplotlib, and analyze the resulting modulated waveform.

Analyze an amplitude-modulated waveform to reveal a high-frequency carrier with a low-frequency envelope and identify components at 100 Hz and 5000 Hz, illustrating frequency response analysis for demodulation.

Learn how Fourier series expresses periodic functions as a sum of sine and cosine terms with a DC component and harmonics, and examine its use and limitations in power electronics.

Explore how the Fourier transform extends Fourier series to nonperiodic signals, turning time functions into frequency spectra with magnitude and phase, and discretize it via the DFT for power engineers.

Learn to implement the one-dimensional discrete Fourier transform with NumPy's FFT to extract magnitudes from complex outputs for power engineering signals.

Learn to apply NumPy's fft and fftfreq to perform a discrete Fourier transform on an output modulated signal, compute magnitudes, and scale results by the time step for meaningful frequencies.

Learn to normalize the frequency range with fftfreq and interpret the mirrored positive and negative frequencies produced by the FFT.

Learn to perform a real-input DFT with rfft, handle mirror negative frequencies, extract the positive spectrum, pad the axis, and double magnitudes to correct for discarded negative components.

Demonstrate frequency modulation and its frequency response using dft, comparing with amplitude modulation, and reveal how the spectrum forms a carrier peak with sidebands spaced by the modulation frequency.

Explore the basics of power electronics, including the distinction between DC and AC systems, key power devices like diodes, MOSFETs, and IGBTs, and how switching strategies shape regulated outputs.

Explore how a two-state switch approximates a cosine waveform in power electronic converters, producing a rectangular output and analyzing its frequency via Fourier methods.

Analyze how a discrete Fourier transform reveals a 50 Hz component in a rectangular waveform and the harmonics, and explain why low-pass or band-pass filters extract it in power electronics.

Explore why power electronic converters use pulse width modulation to synthesize low-frequency waveforms with high-frequency rectangular pulses. Learn sine-triangle modulation, carrier frequency, and switching constraints that enable on-off device control.

Demonstrates implementing pwm in python using a 5000Hz triangular carrier with scipy.signal.sawtooth and vectorized comparison to cosine modulation. Analyzes the pwm with dft/fft for frequency response.

Analyze the pwm output by comparing the cosine modulation signal with a triangular carrier to generate two-level pulses whose widths follow the modulation; confirm a 5000 Hz switching frequency.

Pulse width modulation moves energy to the carrier, preserving a small 50 Hz component for the output, enabling easier, cheaper low-pass filtering than rectangular modulation.

Explore how pulse width modulation uses a high-frequency carrier to produce duty-based rectangular pulses, achieving better frequency response and enabling lighter, cheaper DC-DC converters.

Explore the buck converter, a step-down dc-dc using pulse width modulation and an LC filter to a stable output, covering duty cycle and continuous versus discontinuous conduction.

Install and configure the Python power electronics circuit simulator, choosing web or command-line modes, creating a conda environment, installing dependencies, and launching the Django server to simulate buck converters.

Learn to set up and simulate a buck converter in Python Power Electronics, create the buck converter circuit file, adjust simulation parameters, and prepare for pulse width modulation control.

Develop PWM for a buck converter using a sawtooth carrier within a discrete time control framework. Set time event, sampling time, duty ratio, and carrier frequency to drive PWM output.

This lecture analyzes the buck converter operation with pulse-width modulation, showing how the carrier waveform and duty ratio drive gate signals, currents, and voltages via matplotlib plots.

Perform frequency analysis on switched voltages and the output in a buck converter, compare harmonic content using DFT, and explore DC components and carrier harmonics.

We describe pulse width modulation as a solution to suppress low-frequency harmonics and show improved frequency spectra using a single switch and a buck converter.

Build on pulse width modulation concepts to analyze two-device power converters. Explore the role of the half-bridge module (converter leg), gating constraints, and run simulations in python power electronics.

Expand a buck converter with a second controllable device to achieve boost functionality, forming a buck-boost converter and requiring coordinated switches and diodes.

Learn to simulate the modified buck-boost converter by extending the buck converter in the PPE environment, set up directories and parameters, and resolve polarity-related parameter issues for next steps.

Simulate a modified buck-boost converter, switching between buck and boost modes with S1 and S2, using a Python control file and autoplot outputs to verify operation.

Discover how converter legs or half-bridge modules integrate two controllable devices with antiparallel diodes, built-in gate drivers, and protection circuits to enable compact, reliable bidirectional power conversion.

Learn how a half-bridge converter leg enables a bidirectional dc-dc converter, switching between buck and boost modes to allow energy flow via the inductor and diodes.

Explore simulation of a bidirectional buck converter, enabling power flow both from input to output and from output to input, using a half-bridge circuit and step-by-step circuit setup.

Explore the simulation of a bidirectional buck converter in forward and reverse modes, using S1/S2 switching with diodes D1/D2 and duty ratio to regulate voltages.

Explore bidirectional power flow in a buck converter through simulation, analyzing input and output voltages, capacitor ripple, inductor current, and gate switching strategies.

Analyze the four switching states of a two-device half-bridge, identify the forbidden both-on condition that shorts the supply, and apply dead time for safe complementary gating.

Explore the bidirectional buck-boost converter built from two half-bridge modules linked by an inductor, enabling power flow in both directions and outputs above or below the input.

Explore simulating a bidirectional buck-boost converter by integrating a second half-bridge, using the edge bridge as a building block, and configuring circuit parameters and control files in the circuit simulator.

Simulate a bidirectional buck-boost converter across four operation modes—forward buck, reverse buck, forward boost, and reverse boost—driven by carrier waveform and duty ratio.

Explore four switching modes of a bidirectional buck-boost converter, analyzing voltage and current plots to understand buck and boost operation in forward and reverse directions.

Demonstrate using a half-bridge module as a DC-to-AC inverter, converting a DC source (PV or battery) to AC for an inductive-resistive load with PWM and dead time.

Learn to simulate a dc–ac converter with a half-bridge by adapting a bidirectional buck model, splitting capacitors, and using circuit schematic processing to feed an inductive load or grid.

Learn to simulate a dc-to-ac converter with a half-bridge by using a triangular carrier at 5 kHz, modulated by a 60 Hz cosine signal, and validate S1/S2 gate switching.

Simulate a half-bridge dc-ac converter, analyze ac current and ac voltage plots, and investigate switching behavior, modulation limits, and dc bus current dynamics that limit high-power use.

Explore how pulse width modulation enables flexible two-device converters, learn to identify and avoid dangerous switching conditions in half-bridge modules, and preview full-bridge and three-phase converter designs.

Explore the full bridge converter, built from two half-bridge modules with a common DC source, enabling bidirectional power in DC-DC and DC-AC applications such as solar to grid and UPS.

Explore the full-bridge converter built from two half-bridge modules sharing a common DC bus, capable of driving an AC load. Understand forbidden states, dead time, and safe independent leg switching.

Discover the bipolar pwm strategy for a full-bridge converter, using two independent half-bridge legs to produce plus or minus dc via the first two switching states.

Explore full-bridge intelligent power modules (IPMs) that integrate two half-bridges with gate drivers. Understand DC bus connections, V1 and V2 outputs, protection features, and topologies via datasheets.

Simulate a full-bridge converter with bipolar modulation using a spreadsheet-based workflow; build circuits, edit parameters via csv, and run a python server to generate simulations.

Configure a full-bridge converter with bipolar PWM, using the carrier wave and a cosine modulation. Edit control parameters via Excel or descriptor file and run the simulation.

Analyze and simulate a full-bridge converter with bipolar PWM, examining input/output voltages, current waveforms, and high-frequency ripple, and perform FFT analysis for upcoming unipolar modulation.

This lecture extends bipolar pwm by examining all four switching combinations of a full-bridge module, revealing two active voltage levels and two zero-output freewheeling states.

Represent the full-bridge converter's output voltage as a vector, analyzing transitions between plus, zero, and minus v dc; explore bipolar, unipolar, and space-vector pwm.

Explore unipolar modulation for a full-bridge dc-dc converter and compare it to bipolar modulation. Set up simulations, configure the dc load with a parallel capacitor, and adjust pwm duty cycles.

Simulate a full-bridge dc-dc converter with unipolar modulation, detailing S1–S4 switching for plus, zero, and minus outputs. Analyze carrier comparisons and upcoming algorithm tweaks to support positive and negative voltages.

Explore unipolar PWM for a full-bridge dc-dc converter, illustrating negative duty cycles to generate negative dc output, using complementary switches and positive and negative carrier modulation.

Explains how unipolar pwm generates a unipolar output in a full-bridge dc-dc converter, part 4, detailing gate signals, duty ratio, and carrier waveforms.

Learn to simulate a full-bridge dc–ac converter with unipolar pwm, using two mirror triangular carriers modulated by a sine or cosine signal to produce plus/minus voltages with zero intervals.

Explore phase-shift pwm for a full-bridge dc-dc converter with isolation, using two carrier waveforms to achieve zero average output and avoid transformer saturation, while simulating with a simple RL load.

Explore phase-shift PWM for a full-bridge dc-dc converter, implementing carrier wave phase shift, duty ratio control, and closed-loop regulation in circuit simulation.

Learn to simulate a full-bridge dc-dc converter using phase-shift PWM, generating plus and minus pulses through phase-shifted carrier waves and complementary switch operation.

Analyze the full bridge converter capabilities, build a switching table and vector outputs to visualize and design voltage patterns across bipolar, unipolar, and phase-shift PWM, including practical implementation constraints.

The lecture introduces a basic three-phase converter built from three converter legs for medium- and high-power industrial applications, including motor drives and active filters, with a vector-based SVPWM approach.

Explore the basics of three-phase systems, including star and delta connections, line-to-line and phase voltages, and the distinction between balanced and unbalanced operation.

Explore the topology of a three-phase converter, with three converter legs fed from a common DC source, star connected with isolated neutral, and analyze safe switching patterns and short-circuit constraints.

Explore three-phase power electronic converters, define line-to-line and line-to-neutral output voltages from pole voltages, and simulate a basic three-phase converter feeding an RL load with sine-triangle PWM.

Explore simulating a three-phase converter with sine-triangle PWM by extending a full-bridge model with an extra leg, and configure a star-connected load to study line-to-line and line-to-neutral voltages.

Simulate a three-phase converter with sine-triangle PWM to analyze line and phase voltages and balanced currents. Explore gating signals and modulation signals A, B, C for a bipolar single-carrier scheme.

Evaluate sine-triangle PWM for a three-phase converter with independent legs, then present space vector modulation as a coordinated six-switch strategy to optimize output voltage vectors.

Explore the vector representation of three-phase voltages and space vector modulation for power converters. Learn Clark's ABC to alpha-beta transformation and how six switching states map to rotating vectors.

Compute converter pole voltages from eight switching combinations, apply Clarke's transformation to three-phase outputs, and verify v0 equals zero to reveal alpha and beta vector behavior.

Compute converter output voltage vectors by deriving pole voltages for switching combinations in a three-phase converter. Apply Clark's transformation to alpha beta zero domain and examine line-to-line and line-to-neutral voltages.

Generate vector diagrams in the alpha beta plane for transform voltages using matplotlib's quiver method.

Label six Clarke-derived alpha-beta vectors on a quiver plot using matplotlib's quiver key, assign labels, adjust coordinates, and discuss vector trajectories toward space vector PWM.

Analyze how switching vectors map to the alpha-beta plane using Clarke transformation, defining balanced three-phase outputs from reference voltages.

Plot required output voltage vectors in the alpha beta frame using Clark's transformation, and design coordinated switching sequences with space vector PWM to track target voltages in a three-phase converter.

Explore how pwm pulses create a vector modulation strategy to approximate output voltage vectors with symmetric switching using three-phase gating signals, paving the way for space vector modulation.

Learn space vector PWM (SVPWM) to synthesize any required output voltage vector from converter vectors using zero vectors, with symmetry and minimal switching transitions.

Develop an algorithm to identify converter voltage vectors for space vector modulation using Clarke transform. Determine the two adjacent vectors by vector angle and tangent-based bounds in each quadrant.

Identify converter voltage vector pairs for a given output in part 2 using a quadrant-based algorithm, addressing overflow issues on limited microcontrollers, and preparing sector-based lookup for subsequent implementation.

Develop and test a vector sequence lookup table for space vector modulation, mapping sectors to voltage vectors and ensuring symmetry across the switching cycle.

Compute time intervals for converter voltage vectors in a sector-based switching sequence, extracting v_r alpha/beta, v_x alpha/beta, and v_y alpha/beta, then determine t1, t2, t0 at 5 kHz.

Learn space vector PWM for a three-phase converter, including Clark's transformation, time intervals, vector identification, and preparing switching sequences in a circuit-simulation workflow.

Fixes a bug in SVPWM time-interval calculations by incorporating the DC bus voltage, extends to line-to-line voltages, and prepares gating-signal generation through code generalization.

This SVPWM simulation lecture explains incorporating DC bus voltage, load connection (line-to-neutral vs line-to-line), and calculating time intervals within a switching cycle, illustrating saturation and vector sequencing.

Generate and apply space vector PWM switching states from a seven-vector sequence. Use time intervals T1, T2, and T0 to control gate signals and drive the converter.

Identify the sector and verify the vector sequence in a space vector pwm simulation, generating gate signals and time intervals for robust switching.

Verify sector identification and generate switching signals for SVPWM, plot currents and voltages, compare SVPWM with sine-triangle PWM, and discuss hardware timing accuracy and practical implementation.

Identify and fix the SVPWM gate signal indexing error. Observe corrected phase currents with A, B, C lagging by 180 degrees.

Explore saturation in a three-phase converter under space vector PWM and visualize capacity as a hexagon formed by the converter voltage vectors, scaled by dc bus voltage.

Conclude the three-phase converter's three-leg topology, independent switching states, and space vector PWM using Clarke's transformation. Emphasize the efficiency gains in DC bus use and switching frequency over sine-triangle methods.

Learn to formulate switching strategies for power converters and identify forbidden states, from simple to multi-level topologies. Use simulations with bipolar, unipolar, and space-vector PWM to approach the target output.