The new Unipolar Stepper Motor Driver block in the Drivers library represents a driver specifically configured for use with the Unipolar Stepper Motor block. It connects the two winding center-tap connections A0 and B0 to the positive supply with a voltage equal to the value you provide for the Output voltage amplitude parameter. The A+, A-, B+ and B- ports are then grounded in the appropriate sequence to create the stepping motion. The block initiates a step each time the voltage at the PWM port rises above the Enable threshold voltage.
The Stepper Motor Driver block now has an option to produce the output waveforms required for half-stepping. By default, the driver operates in full-stepping mode, but if you set the Stepping mode parameter to Half stepping, the driver generates an intermediate state between the full steps, in which just one of the A or the B half-windings is powered. As a result, the step size is half of the stepper motor's full step size. The new Unipolar Stepper Motor Driver block also has this option.
Both the Stepper Motor and the Unipolar Stepper Motor blocks now let you account for the torque variation observed when the motor is unpowered and the shaft is rotated. Detent torque is generated by the interaction of the permanent magnet flux and the variation in reluctance as the teeth come in and out of alignment. The new Detent torque parameter represents the amplitude of the sinusoidal torque variation, and the corresponding term is added to the block equations. By default, the parameter value is 0, in which case detent torque is neglected in block computations. Legacy models are not affected.
A new block parameter lets you specify a value for output capacitance:
Modeling the output capacitance is generally important in signal processing applications, as it has measurable effect on circuit behavior. For motor control applications the effect is not as significant, because the other capacitances play a much bigger part in setting turn-on and turn-off dynamics. However, if your datasheet provides a value for output capacitance, you can enter it to increase the block fidelity. The default value is 0, therefore legacy models are not affected.
In previous releases, the Thyristor and N-Channel IGBT blocks have been represented by an equivalent circuit constructed from other semiconductor blocks, such as bipolar transistors and MOSFETs. Now both blocks have an additional representation option, by a lookup table approximation of the on-state current-voltage curve. The main advantages of using this option are increased simulation speed and ease of parameterization. See the block reference pages for details.
In the Thyristor block represented by an equivalent circuit, the underlying model has been enhanced with a pair of back-to-back diodes to allow a wider range of leakage current variation. To help you parameterize your thyristor to match the manufacturer datasheet, two test harnesses have been added to the SimElectronics® examples, Thyristor Static Behavior Validation and Thyristor Dynamic Behavior Validation. See the block reference page for more information.
To take advantage of the additional diodes, the mapping of the block parameters to the equation parameters has been changed. Existing models may need fine-tuning of parameter values to match the exact behavior with previous versions of the block, particularly for parameters associated with dynamics.
The new Voltage-Controlled Oscillator block in the Integrated Circuits library models abstracted behavior of a voltage-controlled oscillator (VCO). VCOs are basic building blocks for RF transmitter and receiver devices, microprocessor clocks, and A-to-D converters. The block models a behavioral representation of a VCO for simulation efficiency.
You have two options for specifying frequency dependence on the input voltage:
Linear — By specifying a coefficient for the rate of change of frequency with input voltage.
Tabulated — By using a lookup table and specifying a vector of input voltages and a corresponding vector of VCO frequencies relative to the nominal frequency.
You also can model the time delay between a change in the input control voltage and the oscillator frequency.
In previous versions, the Servomotor block allowed you to specify the torque-speed envelope only as a set of speed data points and corresponding maximum torque values. Now, you can also define the torque-speed envelope by specifying a maximum torque and a maximum power instead of providing the tabulated torque-speed data.
The block now also accounts for iron losses due to eddy currents. The Torque-independent electrical losses parameter is renamed to Fixed losses independent of torque and speed, and the new Iron losses parameter lets you specify the iron losses at the speed and torque at which efficiency is defined.
In previous versions, the Solar Cell block allowed you to model a single photovoltaic cell. Now, you can model any number of solar cells connected in series using a single Solar Cell block by setting the parameter Number of series cells to a value larger than one. Internally the block still simulates only the equations for a single solar cell, but scales up the output voltage according to the number of cells. This results in a more efficient simulation than if equations for each cell were simulated individually.
If you want to model N cells in parallel, you can do so for single cells by scaling the parameter values accordingly. That is, multiply short-circuit current, diode saturation current, and solar-generated currents by N, and divide series resistance by N. To connect solar cell blocks in parallel, where each block contains multiple cells in series, make multiple copies of the block and connect accordingly.
The new Resistor block in the Passive Devices library models a linear resistor that can optionally generate thermal noise current. The Gaussian noise is generated using the new Random Number source block in the Simscape™ Foundation library. The Repeatability parameter gives you the following options for noise control: not repeatable, repeatable with a random seed, and repeatable with explicitly specified seed.
Legacy models, created in R2009b or earlier and not saved using a more recent version, may need updating if they contain the SPICE Resistor block. If this is the case, upon opening the model you will get a warning saying that the Resistor block does not have a parameter named SCALE. To fix this issue, replace the resistor either with the new Resistor block from the Passive Devices library, or with a new copy of the SPICE Resistor block from the Additional Components/Spice-Compatible Components library.
Two new blocks have been added to the Sources library:
By default, both AC and DC components are set to 0 in each block. Define the AC/DC voltage or current by specifying nonzero values for the appropriate parameters after placing the block in your model.
If you enable the noise component, the Gaussian noise voltage or current, respectively, is generated using the new Random Number source block in the Simscape Foundation library. The Repeatability parameter gives you the following options for noise control: not repeatable, repeatable with a random seed, and repeatable with explicitly specified seed.
The two MOSFET blocks now model gate junction capacitance as a fixed gate-source capacitance and either a fixed or a nonlinear gate-drain capacitance. The IGBT block now models gate junction capacitance as a fixed gate-emitter capacitance and either a fixed or a nonlinear gate-collector capacitance.
If you select the nonlinear option for the charge-voltage linearity, then the gate-drain charge relationship, or the gate-collector charge relationship, respectively, is defined by a piecewise-linear function. For more information, see the respective block reference pages.
The Passive Devices library now contains a sublibrary, named Switches, with four new blocks:
For each switch type, you have an option of modeling turn-on and turn-off delays, that is, a delay between the point at which the voltage at the control port passes the threshold and the point at which the switch opens or closes.
Five new blocks have been added to the Sensors library:
The Accelerometer block provides an abstract model of a MEMS accelerometer. The acceleration at the mechanical translational port is mapped to either a voltage level or the duty cycle of a PWM voltage across the electrical + and - ports. The output voltage is limited according to the values that you provide for maximum and minimum output voltage. Optionally, you can model sensor dynamics by adding a first-order lag between the angular rate at the mechanical port and the corresponding voltage applied to the electrical + and - ports.
The Gyro block provides an abstract model of a MEMS gyroscope. The gyro provides an output voltage that is proportional to the angular rotation rate presented at the mechanical rotational port. The output voltage is limited according to the values that you provide for maximum and minimum output voltage. Optionally, you can model sensor dynamics by adding a first-order lag between the angular rate at the mechanical port and the corresponding voltage applied to the electrical + and - ports.
The PTC Thermistor block models a switching type positive temperature coefficient (PTC) thermistor. This type of thermistor has a decreasing resistance with increasing temperature, up to the Curie temperature. Above the Curie temperature, the resistance increases very rapidly with increasing temperature. To represent a non-switching linear PTC thermistor, use the Thermal Resistor block.
The Pressure Transducer block models a generic pressure transducer that turns a pressure measurement into a voltage. The output voltage is linearly proportional to the pressure. If the pressure is less than zero, the block outputs zero volts. An input pressure equal to the Pressure range parameter value results in an output voltage equal to the Full-scale deflection parameter value. For higher pressures, the output voltage remains at this Full-scale deflection value. You have three choices of operation mode, which let you select between vacuum, atmospheric pressure, or sealed-gauge reference pressure as the reference point for the pressure measurement. You also have an option of approximating the sensor dynamics by a first-order lag.
The Resolver block models a generic resolver, which consists of a rotary transformer that couples an AC voltage applied to the primary winding to two secondary windings. These secondary windings are physically oriented at 90 degrees to each other. As the rotor angle changes, the relative coupling between the primary and the two secondary windings varies. In the Resolver block model, the first secondary winding is oriented such that peak coupling occurs when the rotor is at zero degrees, and therefore the second secondary winding has minimum coupling when the rotor is at zero degrees.
Two new blocks in the Passive Devices library let you take into account nonlinearities in inductors and transformers due to magnetic saturation:
The Nonlinear Inductor block represents an inductor with a core that is nonideal, due to its magnetic properties or dimensions. You have multiple options of block parameterization, including single inductance, single saturation point, magnetic flux versus current characteristic, and magnetic field density versus magnetic field strength characteristic.
The Nonlinear Transformer block is based on the Nonlinear Inductor block and has similar parameterization options, which let you model varying levels of nonlinearity. You can parameterize the transformer winding either by combined primary and secondary values, or by separate values for primary and secondary leakage resistance and inductance.
The new DC-DC Converter block in the Sources library represents a behavioral model of a power converter. The power converter regulates voltage on the load side and the required amount of power is drawn from the supply side to balance input power, output power, and losses. Optionally, the converter can support regenerative power flow from load to supply.
The new Incandescent Lamp block in the Passive Devices library models an incandescent lamp. The key characteristic of this block is that the resistance increases as the filament warms up. The rate of heat loss from the filament is proportional to the filament's temperature difference to ambient. Optionally, you can simulate the fault dynamics by specifying a simulation time at which the lamp fails.
The new Unipolar Stepper Motor block in the Rotational Actuators library represents a stepper motor that has center taps on the two phase windings. All four half-windings are identical. The block lets you simulate thermal effects, and also accounts for iron losses, both in its electrical and thermal equations.
The existing Stepper Motor block has been enhanced to account for iron losses, as well. It now has an additional thermal port HR, corresponding to the rotor and associated iron losses. Additional parameters on the Electrical and Thermal Port tabs let you specify magnetizing resistance, rotor thermal mass and initial temperature, and the percentage of the magnetizing resistance associated with the magnetic path through the rotor.
If your existing model uses a Stepper Motor block with thermal ports exposed, the block now has an additional thermal port HR (corresponding to the rotor and associated iron losses). Leaving this new port unconnected results in a simulation-time error. If iron losses associated with the rotor are not important, you can connect the HR port to an Adiabatic Cup block.
All the blocks in the Rotational Actuators and Translational Actuators libraries, as well as the Solar Cell block in the Sources library, can now have optional thermal ports. By default, the thermal ports are not displayed. To expose the thermal port, right-click on the relevant block in your model, and from the context menu select Simscape block choices > Show thermal port. This action displays the thermal port H on the block icon, and adds the Thermal port tab to the block dialog box.
This functionality is not always available for blocks in existing models, depending on when the model was last saved. If you right-click on a block in a model saved in a previous version, and the context menu item Simscape block choices does not appear, make a new copy of the block from the SimElectronics library.
The new Fully Differential Op-Amp block in the Integrated Circuits library models an operational amplifier with fully differential output, that is, not referenced to ground. The output common-mode voltage is controlled by the common-mode port cm. Internal resistors set the nominal output common-mode voltage to be midway between the values you provide for the positive and negative supply voltages. Applications include data acquisition where inputs are differential, for example, sigma-delta converters.
The block provides a behavioral model of a fully differential operational amplifier. It does not represent nonlinear effects, such as variation in gain with output voltage amplitude, and the nonlinear nature of the output voltage-current relationship for large load currents.
The new Transmission Line block in the Passive Devices library lets you model a transmission line either by using delays, or by a lumped parameter model. Use the delay-based models for better simulation performance at system level. The lossless delay-based model represents an ideal transmission line.
The new Power Sensor block in the Sensors library calculates the power taken by the load connected across the + and - terminals under the assumption that only the load is connected to the + terminal.
The sensor can return either instantaneous power, or power averaged over a fixed time period. The latter option is useful when working with periodic current and voltage waveforms, such as those associated with PWM control.
The usability of the Induction Motor block has been improved. In previous versions, when setting Model parameterization to By motor ratings, you had to provide a value for either the motor starting current or maximum torque. This group of parameters has been removed, and instead the Rated RMS line current parameter value is used to determine the total motor inductance. In existing models, if you used consistent values for RMS starting (or locked rotor) line current and Rated RMS line current, simulation results are the same as in previous versions.
The Controlled PWM Voltage block has two new parameters, Pulse delay time and Pulse width offset. Use these parameters to add a small turn-on delay and a small turn-off advance. This can be helpful when fine-tuning switching times, to minimize switching losses.
The Diode block now lets you model charge dynamics. The Exponential diode model contains an additional set of parameters that let you either specify values for the transit time and carrier lifetime directly, or calculate them using the peak reverse current and reverse recovery time. This functionality is especially useful for applications such as commutation diodes.
Demos introduced in this version are:
All the blocks in the Semiconductors library, as well as the Photodiode and Light-Emitting Diode blocks in the Sensors library, can now have optional thermal ports. By default, the thermal ports are not displayed. To expose the thermal port, right-click on the relevant block in your model, and from the context menu select Simscape block choices > Show thermal port. This action displays the thermal port H on the block icon, and adds the Thermal port tab to the block dialog box.
In the N-Channel IGBT block, several new parameters on the Advanced tab have been added, to better match the typical device datasheets. The Forward Early voltage, VAF parameter, with the default value of 200 V, specifies the Forward Early voltage for the PNP transistor. Previously the effect was not modeled. This means that existing models will show small differences in the current-voltage relationship associated with the PNP bipolar transistor, compared to the previous version. Additionally, the new Collector resistance, RC and Emitter resistance, RE parameters have nonzero default values, to improve the numeric efficiency of computations. If you want to preserve the simulation results for the existing models, set Forward Early voltage, VAF to 1e10, Collector resistance, RC to 0, and Emitter resistance, RE to 0.
The Operational Transconductance Amplifier block, added to the Integrated Circuits library, provides a behavioral representation of an operational transconductance amplifier. A transconductance amplifier converts an input voltage into an output current. Applications include variable frequency oscillators, variable gain amplifiers, and current-controlled filters. These applications are based on the fact that the transconductance gain is a function of current flowing into the control current pin.
The block does not model the detailed transistor implementation. This results in faster simulation, but the model is only valid when operating in the linear region, that is, where the device input resistance, output resistance, and transconductance gain all depend linearly on the control current, and are independent of input signal amplitude.
The Push-Pull Output block, added to the Integrated Circuits library, provides a behavioral representation of a CMOS complementary output stage. To improve simulation speed, the block does not model all the internal individual MOSFET devices that make up the gate You can use this block to create a representative output current-voltage relationship when defining an integrated circuit model behavior with Physical Signal blocks from the Simscape Foundation library. For an example, see the Modeling an Integrated CircuitModeling an Integrated Circuit demo.
The following enhancements have been implemented for the H-Bridge block:
In Averaged mode, a new Load current characteristics parameter is available with two options, Smoothed and Unsmoothed or discontinuous. The first option assumes that the current is practically continuous due to load inductance, and corresponds to the old block behavior. For cases where the current is not smooth, or goes to zero between PWM cycles, use the Unsmoothed or discontinuous option, and provide values for the new Total load series resistance, Total load series inductance, and PWM frequency parameters. During simulation, the block uses these values to calculate a more accurate value for H-bridge output voltage that achieves the same average current as would be present if simulating in PWM mode.
The Freewheeling mode parameter is now available not only in PWM mode, but also in Averaged mode in cases where you select Unsmoothed or discontinuous for the Load current characteristics parameter.
An additional Freewheeling mode option, Via two semiconductor switches and one freewheeling diode, controls the load by maintaining one high-side bridge arm permanently on and using the PWM signal to toggle between enabling the corresponding low-side bridge arm and the opposite high-side bridge arm. This means that the block uses a freewheeling diode in parallel with a bridge arm, plus another series bridge arm, to complete the dissipation circuit when the bridge turns off.
The block dialog box has been reorganized using tabs, to improve usability.
The DC Motor block has an additional option that lets you use no-load current data to calculate a value for rotor damping. This is helpful when the manufacturer datasheet does not provide an explicit rotor damping value.
The Rotor damping parameterization drop-down has been added to the Electrical Torque tab of the block dialog box, with the following values:
By damping value — Specify a value for rotor damping directly, by using the Rotor damping parameter on the Mechanical tab. This is the default.
By no-load current — The block calculates rotor damping based on the values that you specify for the No-load current and DC supply voltage when measuring no-load current parameters. If you select this option, the Rotor damping parameter is not available on the Mechanical tab.
Previously, if the Model parameterization parameter was set to By stall torque & no-load speed or By rated power, rated speed & no-load speed, the block did not take rotor damping into account. The new block equations always include rotor damping, because it is now tied to no-load current. Therefore, rated speed and no-load speed results for existing models using these options will be slightly different than in previous versions if the model has a nonzero damping value.
If you wish to retain the original behavior, set the rotor damping to zero, and add an external Rotational Damper block (from Simscape Foundation library) across the motor R and C ports.
Demos introduced in this version are:
Dialog boxes of most of the blocks in the Semiconductors library, and some related blocks, now have a new tab, Temperature Dependence, which lets you specify additional parameters to model the temperature dependence during simulation. For details, see reference pages of the following blocks:
In NPN and PNP Bipolar Transistor blocks, a new parameter, Collector-emitter voltage at which h-parameters are defined, has been added. It serves to increase the accuracy with which equation parameters are calculated from h-parameters, to better capture current gain dependence on temperature. As a result, when you use Specify from a datasheet for the Parameterization parameter, there is a small change in the resulting transistor gain BF (calculated from the Forward current transfer ratio h_fe parameter value), compared to the previous version of the block.
Demos introduced in this version are:
Change to an existing demo:
The new Thyristor block, located in the Semiconductor Devices library, represents a thyristor modeled using an NPN and a PNP transistor. The collector of each device is connected to the base of the other device so as to give the P-N-P-N junction structure of a thyristor.
The new Multiplier block, located in the Integrated Circuits library, represents an integrated circuit multiplier for physical signals. It allows you to multiply and divide signals without switching to Simulink signals and back.
When using the Diode block, with the Diode model parameter set to Exponential, you now have two additional options under Parameterization:
Use an I-V data point and IS — Specify measured data at a single point on the diode I-V curve in combination with the saturation current.
Use an I-V data point and N — Specify measured data at a single point on the diode I-V curve in combination with the emission coefficient.
See the block reference page for details.
The Junction Capacitance tab has been renamed to Capacitance, and the two existing parameters on it have been renamed:
Base-emitter capacitance to Base-emitter junction capacitance
Base-collector capacitance to Base-collector junction capacitance
Two new parameters have been added to the Capacitance tab:
Total forward transit time, representing the mean time for the minority carriers to cross the base region from the emitter to the collector
Total reverse transit time, representing the mean time for the minority carriers to cross the base region from the collector to the emitter
Default values for ohmic resistances have been changed to RB = 1 Ω, RC = 0.01 Ω, and RE = 1e-4 Ω, to be consistent with the SPICE-compatible library.
The new Potentiometer block, located in the Passive Devices library, represents a potentiometer, where the wiper position is controlled by the input physical signal.
The dialog boxes of blocks in the Logic library now have an additional tab, Initial Conditions, which lets you specify the output initial state (low or high). See the respective block reference pages for details.
The ability to parameterize SimElectronics blocks by importing circuit data from a SPICE netlist is no longer supported. As a result, using the netlist2sl function is no longer recommended. See Parameterizing Blocks from Datasheets for alternative ways of block parameterization. Additional related changes introduced in this version are:
The SPICE-compatible blocks have been moved to the Additional Components library. They are organized in sublibraries according to function, for example, the SPICE-Compatible Sources library is now the Sources sublibrary of the Additional Components/SPICE-Compatible Components library. The Resistor block, renamed SPICE Resistor, and the Current-Controlled Switch and Voltage-Controlled Switch blocks have been moved to the Passive Devices sublibrary of the Additional Components/SPICE-Compatible Components library.
Some of the blocks have been renamed so that their names start with the "SPICE" prefix. The following table lists the old and new block names.
|Old Name||New Name|
|Diode (SPICE)||SPICE Diode|
There are no compatibility considerations as a result of renaming the SPICE-compatible blocks and moving them to the Additional Components library. Your existing models will be updated automatically when you open and save them in the new version.
In previous versions, the Solar Cell block had the option of using the SPICE Environment Parameters block to set temperature. This is removed in R2010a to eliminate dependency on the SPICE sublibrary. Also, the Solar Cell model now uses the regular Diode block (exponential diode) rather than the SPICE Diode block.
There is an insignificant change in results, of the order of 1e-12, in the Solar Cell block because of the diode replacement.
Demos introduced in this version are:
|Function or Function Element Name||What Happens When you use the Function or Element?||Use This Instead||Compatibility Considerations|
Issues a warning that it is not supported and may be removed in future releases
See Parameterizing Blocks from Datasheets for alternative ways of block parameterization
New features and changes introduced in this version are:
The Generic Rotary Actuator block models the torque-speed characteristics of a generalized rotary actuator.
The Generic Linear Actuator block models the force-speed characteristics of a generalized linear actuator.
The Servomotor block now allows for the specification of additional parameters from within the Block Parameters dialog box.
During simulation, the updated Servomotor block is backwards-compatible with models defined in earlier versions of the software. However, the model generates a warning in this version because the block dialog box supports additional unit options for torque and speed data. To remove the warnings, open the block dialog box and select appropriate units for the torque and speed data.
The new Timer block, located in the Integrated Circuits library, is an abstracted behavioral model of a timer integrated circuit, such as the NE555.
New features and changes introduced in this version are:
The Actuators & Drivers library now contains blocks for modeling piezoelectric travelling wave motors. The library contains these new blocks:
The H-Bridge block now provides the option to dissipate current via two freewheeling diodes when the signal at the PWM port is low. To use this new option, select Via two freewheeling diodes for the Freewheeling mode parameter.
New features and changes introduced in this version are:
The Passive Devices library now contains a Resistor block to model a resistor as a function of temperature and process data.
The Passive Devices library now contains a Crystal block to model the electrical characteristics of a crystal resonator.
The Variable Inductor and Variable Capacitor blocks have the following enhancements:
The Variable Inductor block now provides two options for the relationship between the voltage across the device and the current through the inductor. The new Equation parameter lets you select the voltage-current equation that you want.
The Variable Capacitor block now provides two options for the relationship between the current through the device and the voltage across the capacitor. The new Equation parameter lets you select the current-voltage equation that you want.
New features and changes introduced in this version are:
The Solar Cell block has the following enhancements:
The block now provides the option to use an 8-parameter model that includes an additional diode and a parallel resistor.
The block now models temperature dependence.
The SPICE-Compatible Sources library (in the Sources library) contains blocks for modeling dependent sources with two controlling inputs. The library contains these new blocks:
PCCCS2 — Model polynomial current-controlled current source with two controlling inputs
PCCVS2 — Model polynomial current-controlled voltage source with two controlling inputs
PVCCS2 — Model polynomial voltage-controlled current source with two controlling inputs
PVCVS2 — Model polynomial voltage-controlled voltage source with two controlling inputs
The Actuators & Drivers library now contains a Piezo Stack block to model the electrical and force characteristics of a piezoelectric stacked actuator.
The Passive Devices library now contains a Relay block to model the resistive and delay characteristics of a relay controlled by an external physical signal.
The Passive Devices library now contains a Fuse block to model the following fuse characteristics:
Rated current at which the fuse blows when exceeded for a specified amount of time.
SimElectronics software is a modeling environment for the engineering design and simulation of electronic and electromechanical systems within the Simulink® environment.
Version 1.0 includes these features:
A library of electronic and electromechanical blocks that model components such as:
For these blocks, you enter key parameter values directly from industry datasheets.
For more information about the available blocks, see SimElectronics Block Libraries.
A function, netlist2sl, for creating library blocks that represent circuit data in a SPICE netlist.
Ability to convert SimElectronics models to C code.
For more information about code generation, see Code Generation in the Simscape documentation.
Access to linearization and steady-state solve capabilities in Simscape.
For more information about linearization, see Linearizing at an Operating Point in the Simscape documentation.
For more information about how Simscape solves models, see How Simscape Simulation Works in the Simscape documentation.
|Release||Features or Changes with Compatibility Considerations|
|R2014a||Thyristor block that now models devices with higher leakage currents|
|R2013a||Resistor with optional thermal noise|
|R2012b||Unipolar Stepper Motor block and Stepper Motor block that now account for iron losses|
|R2011a||Thermal Dependency Added to Semiconductor Blocks|
|R2009b||Actuators & Drivers Library Blocks|