Simulation and Analysis

Performance improvement, analysis tools and techniques

Analyze, tabulate, and plot harmonic data using analysis functions and Simscape™ logging variables. Simulate thermal losses due to switching events and conduction losses in semiconductors. Perform a load-flow analysis and use the results to initialize AC steady state simulation.

Simscape Blocks

Busbar	Load flow analysis busbar connector
Load Flow Source	Three-phase voltage source for performing load flow analysis

Functions

`ee_calculateFluxPartialDerivatives`	Calculate flux partial derivatives for FEM-Parameterized PMSM block
`ee_calculateThdPercent`	Compute the total harmonic distortion (THD) percentage
`ee_comtradeDataset`	Read and extract values from COMTRADE record (Since R2020b)
`ee_getBillOfMaterials`	Generate report for current model and all subsystems (Since R2020b)
`ee_getCauerFromFoster`	Get equivalent resistance and capacitance vectors for Cauer Thermal Model block from Foster Thermal Model block (Since R2022b)
`ee_getEfficiency`	Calculate efficiency as function of dissipated power losses
`ee_generateIdealPMSMfluxData`	Generate tabulated flux linkage data for ideal PMSM
`generateMotorDriveROM`	Generate reduced-order model of motor drive system (Since R2024a)
`generateSemiconductorSwitchROM`	Generate reduced-order model of semiconductor switch (Since R2024b)
`ee_getHarmonics`	Return harmonic orders, magnitudes, and fundamental frequency
`ee_getNodeDvDtSummary`	Calculate maximum absolute values of terminal voltage time derivatives (dv/dt) based on logged simulation data
`ee_getNodeDvDtTimeSeries`	Calculate rates-of-change of voltage variables
`ee_getPowerLossSummary`	Calculate dissipated power losses and switching losses
`ee_getPowerLossTimeSeries`	Calculate dissipated power losses and switching losses, and return time series data
`ee_importDeviceParameters`	Parameterize ideal semiconductor block from Hitachi or Infineon XML file (Since R2021b)
`ee_plotHarmonics`	Plot percentage of fundamental magnitude versus harmonic order

Analysis Tools

Harmonic Analyzer	Analyze and plot harmonic spectrum of Simscape logging nodes
Load-Flow Analyzer	Determine steady-state voltage magnitudes and angles and real and reactive power flows for three-phase AC, DC, or mixed AC/DC network

Topics

Examine the Simulation Data Logging Configuration of a Model
Determine if data logging is enabled for your model.
Choose a Simscape Electrical Function for an Offline Harmonic Analysis
Explore the capabilities of Simscape Electrical™ harmonic analysis functions.
Perform an Online Harmonic Analysis Using the Simscape Spectrum Analyzer Block
Learn how to analyze harmonic distortion using the Spectrum Analyzer block.
Perform a Power-Loss Analysis
Calculate power losses for Simscape Electrical semiconductor blocks.
Perform a Load-Flow Analysis Using Simscape Electrical
Learn how to perform a power-flow, or load-flow, analysis for a three-phase Simscape Electrical network using the Simscape three-phase electrical domain.
Optimize Block Settings for Simulating with the Partitioning Solver
Avoid simulation errors by configuring models for simulation with the specific solvers by using the ee_updateSolver function.
Phasor-Mode Simulation Using Simscape Components
Configure your model to use frequency-time equation formulation.

Featured Examples

Composite Three-Phase Rectifier

This is the base model for analysis workflow examples.

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Harmonic Analysis of a Three-Phase Rectifier

Use functions which analyze Simscape™ logging data to get harmonic magnitudes, calculate total harmonic distortion percentage and plot harmonic magnitudes. The model to which this analysis is applied is of a three-phase rectifier. The functions demonstrated are:

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2-Bus Loadflow

A model of a two-bus three-phase power system network. The model uses three instances of the Load Flow Source block from Simscape™ Electrical™, one configured to be the swing bus, one configured to be the PV bus, and one configured to be the PQ load. The PV bus regulates its output to be at a voltage of 1.025 times rated voltage and to deliver 80MW active power to the network. The Swing bus regulates voltage at the other end of the transmission line to be one times rated voltage, and it delivers the requisite power to the network so that overall active and reactive powers balance. The Simscape initialization solver determines the required internal initial voltage amplitudes and phases in both the PV bus and the Swing bus so as to start in steady state.

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IEEE 9-Bus Loadflow

A model of a 9-bus three-phase power system network. This example is based on an IEEE® benchmark test case, further details of which can be found in "Power System Control and Stability" by P. M. Anderson and A. A. Fouad (IEEE Press, 2003). Simscape™ initializes two of the generators to the specified powers and terminal voltages, and initializes the remaining swing bus generator to meet just the specified voltage. The resulting load flow solution is appended to each of the busbars post-simulation. The four rows correspond to per-unit voltage, phase, active power, and reactive power respectively. Looking at Bus 1, it can be seen from the annotation that the swing generator delivers 76.4MW of active power and 27.5MVAr or reactive power to the network. Differences to the original benchmark are due to the transmission line models and transformer configurations used.

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IEEE 9-Bus System

Model a 9-bus three-phase power system network. This example is based on the IEEE® benchmark test case. For more information, see "Power System Control and Stability" by P. M. Anderson and A. A. Fouad (IEEE Press, 2003)

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Induction Motor Initialization with Loadflow

Initialize a three-phase induction motor as part of a load flow analysis. When initializing an induction machine that is directly connected to an AC network, in steady state there is one degree of freedom which you can set by any one of shaft torque, shaft power, motor speed, or electrical power.

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Synchronous Machine Initialization with Loadflow

Initialize synchronous machine as part of a load flow analysis. When initializing a synchronous machine there are two degrees of freedom which can be set by any two of rotor angle, active power, reactive power and terminal voltage. The pair of variables that are constrained is set by the source type drop-down menu, this having options of Swing bus, PV bus and PQ bus. Here the machine is configured for a swing bus with a 1.02 per-unit voltage and zero degrees phase.

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JFET Amplifier and Frequency Response Analysis

An audio amplifier circuit based on an N-channel JFET. The desired operating point is taken to be Vds=5V, Id=2mA and Vgs=-2V. The manufacturer datasheet gives the JFET forward transfer conductance and output conductance values as 3mS and 50uS. These values are used to populate the mask of the N-Channel JFET block.

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Power-Loss Analysis of a Three-Phase Rectifier

Perform a power-loss analysis using the ee_getPowerLossSummary function and the power_dissipated variable. The Rectifier contains six Diode blocks. Diodes D1, D2, D4, and D5 each dissipate, on average, 52.19 W over the course of the 0.5 second simulation. Diodes D3 and D6 each dissipate an average of 52.22 W for the same time period because they experience a 340 W transient power-dissipation spike due to DC-load capacitor charging before t = 1e-3 s. For each diode, the average power dissipated when the rectifier is operating in steady-state, t = 0.4 to 0.5 s, is 52.19 W.

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Calculate Losses in a Power Converter

Calculate the losses in a power converter using the ee_getPowerLossSummary function and the power_dissipated variable. The power converter contains six Diode blocks. Diodes D1, D2, D4, and D5 each loose, on average, 52.19 W over the course of the 0.5 second simulation. Diodes D3 and D6 each loose an average of 52.22 W for the same time period because they experience a 340 W transient power-dissipation spike due to DC-load capacitor charging before t = 1e-3 s. For each diode, the average power loss when the power converter is operating in steady-state, t = 0.4 to 0.5 s, is 52.19 W.

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Mixed AC/DC System Loadflow

Use the Load Flow Analyzer to review the load flow results of a mixed AC/DC system. The model to which this analysis is applied includes an AC load flow source, a three-phase rectifier, and three loads. One of the loads is AC, one is permanently connected on the DC side, and one is switched on the DC side.

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