Simulation error still occurs перевод

Multisim and Ultiboard

Convergence Assistant (Op-Amp error)

Convergence Assistant (Op-Amp error)

‎06-26-2009 07:54 PM

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this is my first post here and I’m familiar with Multisim on a basic level. I created my sim file based on a schematic that I did not design. I am getting the error:

A simulation error has occurred. Would you like to run the Convergence Assistant to attempt to resolve this problem automatically?

Most everytime I hit yes, the convergence assistant is able to solve the problem, but it is unable to fix this circuit. I believe the problem is with the op-amps and have been trying to tinker around to fix.

1. JPG of sim file
2. GIF of source schematic
3. multisim file

Any ideas? Thanks.

By the way, this is a pulse width modulator used to keep the rms current constant.

Re: Convergence Assistant (Op-Amp error)

‎06-29-2009 03:10 PM

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I took a look at your circuit, and it looks like the convergence issue lies in the model you are using. The model is a 3-terminal opamp; that is, only the input and output pins are modelled, and not the power supplies. This causes issues in your particular circuit because you have some opamps in open-loop configurations expecting that the output will be clipped at the supply voltages. But because the power supplies are not modelled, the output is not being clipped, and therefore very large voltage values are occurring at the outputs.

I replaced the model you are currently using in the circuit (IIT/LM324A) with another one that does model the power supplies (IIT/LM324A_2). Looks like this solved the convergence issue. The modified file is attached. There are also vendor-specific LM324 models in the database in case you are using a vendor specific component (depending on your version of Multisim).

Let us know if this solves the issue.

Natasha Baker
R&D Engineer
National Instruments

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Simulation error still occurs

Simscape™ simulations can stop before completion with one or more error messages. This section discusses generic error types and error-fixing strategies. You might find the previous section, How Simscape Simulation Works, useful for identifying and tracing errors.

If a simulation failed:

Review the model configuration. If your error message contains a list of blocks, look at these blocks first. Also look for:

Wrong connections — Verify that the model makes sense as a physical system. For example, look for actuators connected against each other, so that they try to move in opposite directions, or incorrect connections to reference nodes that prevent movement. In electrical circuits, verify polarity and connections to ground.

Wrong units — Simscape unit manager offers great flexibility in using physical units. However, you must exercise care in specifying the correct units, especially in the Simulink-PS Converter and PS-Simulink Converter blocks. Start analyzing the circuit by opening all the converter blocks and checking the correctness of specified units.

Try to simplify the circuit. Unnecessary circuit complexity is the most common cause of simulation errors.

Break the system into subsystems and test every unit until you are positive that the unit behaves as expected.

Build the system by gradually increasing its complexity.

It is recommended that you build, simulate, and test your model incrementally. Start with an idealized, simplified model of your system, simulate it, verify that it works the way you expected. Then incrementally make your model more realistic, factoring in effects such as friction loss, motor shaft compliance, hard stops, and the other things that describe real-world phenomena. Simulate and test your model at every incremental step. Use subsystems to capture the model hierarchy, and simulate and test your subsystems separately before testing the whole model configuration. This approach helps you keep your models well organized and makes it easier to troubleshoot them.

System Configuration Errors

Missing Solver Configuration Block

Each topologically distinct Simscape block diagram requires exactly one Solver Configuration block to be connected to it. The Solver Configuration block specifies the global environment information and provides parameters for the solver that your model needs before you can begin simulation.

If you get an error message about a missing Solver Configuration block, open the Simscape Utilities library and add the Solver Configuration block anywhere on the circuit.

If your model contains hydraulic elements, each topologically distinct hydraulic circuit in a diagram requires a Custom Hydraulic Fluid block (or Hydraulic Fluid block, available with Simscape Fluids™ block libraries) to be connected to it. These blocks define the fluid properties that act as global parameters for all the blocks connected to the hydraulic circuit. If no hydraulic fluid block is attached to a loop, the hydraulic blocks in this loop use the default fluid. However, more than one hydraulic fluid block in a loop generates an error.

Similarly, more than one Thermal Liquid Settings (TL) block in a thermal liquid circuit, Two-Phase Fluid Properties (2P) block in a two-phase fluid circuit, or Gas Properties (G) block in a gas circuit generates an error.

If you get an error message about too many domain-specific global parameter blocks attached to the network, look for an extra Hydraulic Fluid block, Custom Hydraulic Fluid block, Thermal Liquid Settings (TL) block, Two-Phase Fluid Properties (2P) block, or Gas Properties (G) block and remove it.

Missing Reference Block

Simscape libraries contain domain-specific reference blocks, which represent reference points for the conserving ports of the appropriate type. For example, each topologically distinct electrical circuit must contain at least one Electrical Reference block, which represents connection to ground. Similarly, hydraulic conserving ports of all the blocks that are referenced to atmosphere (for example, suction ports of hydraulic pumps, or return ports of valves, cylinders, pipelines, if they are considered directly connected to atmosphere) must be connected to a Hydraulic Reference block, which represents connection to atmospheric pressure. Mechanical translational ports that are rigidly clamped to the frame (ground) must be connected to a Mechanical Translational Reference block, and so on.

If you get an error message about a missing reference block, or node, check your system configuration and add the appropriate reference block based on the rules described above. The missing reference node diagnostic messages include information about the particular block and variable that needs a reference node. This is especially helpful when multiple domains are involved in the model. For more information and examples of best modeling practices, see Grounding Rules.

Basic Errors in Physical System Representation

Physical systems are represented in the Simscape modeling environment as Physical Networks according to the Kirchhoff’s generalized circuit laws. Certain model configurations violate these laws and are therefore illegal. There are two broad violations:

Sources of domain-specific Across variable connected in parallel (for example, voltage sources, hydraulic pressure sources, or velocity sources)

Sources of domain-specific Through variable connected in series (for example, electric current sources, hydraulic flow rate sources, force or torque sources)

These configurations are impossible in the real world and illegal theoretically. If your model contains such a configuration, upon simulation the solver issues an error followed by a list of blocks, as shown in the following example.

Example. The model shown in the following illustration contains two Ideal Translational Velocity Sources connected in parallel. This produces a loop of independent velocity sources, and the solver cannot construct a consistent system of equations for the circuit.

When you try to simulate the model, the solver issues an error message with links to the Ideal Translational Velocity Source and Ideal Translational Velocity Source1 blocks. To fix the circuit, you can either replace the two velocity sources by a single Ideal Translational Velocity Source block, or add a Translational Damper block between them.

Numerical Simulation Issues

Numerical simulation issues can be either a result of certain circuit configurations or of parameter discontinuities.

Dependent Dynamic States

Certain circuit configurations can result in dependent dynamic states, or the so-called higher-index differential algebraic equations (DAEs). Simscape solver can handle dependencies among dynamic states that are linear in the states and independent of time and inputs to the system. For example, capacitors connected in parallel or inductors connected in series will not cause any problems. Other circuit configurations with dependent dynamic states, in certain cases, may slow down the simulation or lead to an error when the solver fails to initialize.

Problems may occur when dynamic states have a nonlinear algebraic relationship. An example is two inertias connected by a nonlinear gear constraint, such as an elliptical gear. In case of simulation failure, the Simscape solver may be able to identify the components involved, and provide an error message with links to the blocks and to the equations within each block.

Parameter Discontinuities

Nonlinear parameters, dependent on time or other variables, may also lead to numerical simulation issues as a result of parameter discontinuity. These issues usually manifest themselves at the transient initialization stage (see Transient Simulation Issues).

Initial Conditions Solve Failure

The initial conditions solve, which solves for all system variables (with initial conditions specified on some system variables), may fail. This has several possible causes:

System configuration error. In this case, the Simulation Diagnostics window usually contains additional, more specific, error messages, such as a missing reference node, or a warning about the component equations, followed by a list of components involved. See System Configuration Errors for more information.

Dependent dynamic state. In this case, the Simulation Diagnostics window also may contain additional, more specific, error messages, such as a warning about the component equations, followed by a list of components involved. See Dependent Dynamic States for more information.

The residual tolerance may be too tight to produce a consistent solution to the algebraic constraints at the beginning of simulation. You can try to increase the Consistency Tolerance parameter value (that is, relax the tolerance) in the Solver Configuration block.

If the Simulation Diagnostics window has other, more specific, error messages, address them first and try rerunning the simulation. See also Troubleshooting Tips and Techniques.

Transient Simulation Issues

Transient initialization happens at the beginning of simulation (after computing the initial conditions) or after a subsequent event, such as a discontinuity (for example, when a hard stop hits the stop). It is performed by fixing all dynamic variables and solving for algebraic variables and derivatives of dynamic variables. The goal of transient initialization is to provide a consistent set of initial conditions for the next transient solve step.

Transient Initialization Not Converging

Error messages stating that transient initialization failed to converge, or that a set of consistent initial conditions could not be generated, indicate transient initialization issues. They can be a result of parameter discontinuity. Review your model to find the possible sources of discontinuity. See also Troubleshooting Tips and Techniques.

You can also try to decrease the Consistency Tolerance parameter value (that is, tighten the tolerance) in the Solver Configuration block.

A typical step-size-related error message may state that the system is unable to reduce the step size without violating the minimum step size for a certain number of consecutive times. This error message indicates numerical difficulties in solving the Differential Algebraic Equations (DAEs) for the model. This might be caused by dependent dynamic states (higher-index DAEs) or by the high stiffness of the system. You can try the following:

Tighten the solver tolerance (decrease the Relative Tolerance parameter value in the Configuration Parameters dialog box)

Specify a value, other than auto , for the Absolute Tolerance parameter in the Configuration Parameters dialog box. Experiment with this parameter value.

Tighten the residual tolerance (decrease the Consistency Tolerance parameter value in the Solver Configuration block)

Increase the value of the Number of consecutive min step size violations allowed parameter in the Configuration Parameters dialog box (set it to a value greater than the number of consecutive step size violations given in the error message)

Review the model configuration and try to simplify the circuit, or add small parasitic terms to your circuit to avoid dependent dynamic states. For more information, see Numerical Simulation Issues.

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Simulation error in time dependent study

Posted 30 окт. 2012 г., 14:43 UTC Battery Design Version 5.2a 9 Replies

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I’m closely following the built-in tutorial model «coil above plate», so I’m using the magnetic field (mf) physics with the single-turn coil domain and so on. The only difference is that I’m not working in 2D asymetric but in 3D.

The problem is that I have an error message «Failed to find initial solution. Singular matrix. For mesh case 0 there are degrees of freedom that do not occur in any equation (empty columns in matrix) for the variable mod1.mf.VCoil. Last time step is not converged» when simultaing in transient domain.

Since I’ve done almost the same steps of the coil above plate but in 3D, I’m stuck in this awkward situation and it’s really important for me to overcome it.

So I’ll be extremely grateful for any help, please.

Thanks for your help

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It sounds that you are forgetting the gap in the coils (unless you want a closed-loop condition). Sorry if I am mistaken. Notice that in 2D-axisymmetric, when a simple circle (torus in 3D) is set as a coil domain, COMSOL is considering it having an infinitesimal gap, in order to feed it (with some non-null voltage), but so small that the magnetic field it creates is equal to that of a perfect torus. If you model the coil in 3D, you must include the gap in the geometry, as a small discontinuity (full of air, generally). In the ends of the torus (borders of the gap) you can set both terminal conditions for the coil.

I hope this helps you.

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Thanks for your reply Jesus.

But if I understood correctly what you’re talking about, I think I’ve already included the gap. In fact, in the definitions node I added an «Infinite Element domain 1» which is the air around the coils and an «Adjacent 1» which is the coils with «Exterior boudaries» checked in «output entity». Is that what you’re talking about? If not, could you be more specific regarding the means to do so please?

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No, I wasn’t talking about the infinite elements around all the geometry (including the surrounding air). I referred to a little breaking (a physical discontinuity) in the conductor itself, unless you are modelling that coil as a secondary closed circuit (I think this is not the case).

Have a look to the documentation of AC/DC module, particularly to «AC/DC Module > Modeling with the AC/DC Module > Coil Domains > Using Coils in 3D Models», or see the «inductor_3d» model.

Thus, in your 3D model, you can do something similar: cut the torus of the primary circuit with two closed planes (for instance, adding, by duplicating the original torus, another torus with only 1 deg for the revolution angle), then extract that gap domain from the study (from the Magnetic Fields physics), and finally setting the gap boundaries with suitable conditions (current / voltage / circuit . ).

I hope this helps you.

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If I understood well the explanation in v4.3a, you do not even need a «gap» in 3D (which is not physical and introduces other artefacts) but you need to have a cut surface to define the Coil total area, and a loop line for the current flow direction

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Thanks for the reply.

So, I tried what you said and this is what I did : I created another torus with 1 degree and set it as an air material. Then I excluded it from the mf study. Afterwards, in the «single-turn coil domain» node, I added a «boundary feed» sub-node and set it as the boundary of the new torus, with 1 A coil excitation, and I added a «Ground» sub-node set as the other boundary of the gap torus.

Unfortunatly, I still get the same error when I run the time dependent simulation. I’m getting really desperate 🙁

Have I done something wrong? Can you help me further pretty please? 🙁

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first of all you need a block or a sphere to enclose fully your coil to get the field to loop around, not too big to avoid RAM crash, and not too small to allow the field to loop unafected, but MF should cover air + coil !

Then if you have only an average current, or an oscillating current, the easiest torus type coil is obtained by defining a cylindrical coordinates with axis along the torus ring then to add a current density J0 along phi from this coordinate.

The single turn coil is also possible ,bit it reauires more exercicing, too long to explain here, there are some new model library cases.

The multi-turn coil is the most complex and require quite some additional sub-nodes, mostly I need also to add an A gauge. you need to study the help file, then build very simple models and go step ba step, ne physics at the time until you are fully comfortable with all domain and BC settings

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Thanks for your reply.

So, I tried what you said to no avail, knowing that I’m already using an air sphere of 1 meter radius around the coil. This is what I did :

— I defined a cylindrical coordinate system then I included in the coil domain a » Single Turn Domain » node and «external current density» node with 1 A/m² along phi. Still, when running the time dependent I get the «Failed to find initial solution» error.

— Like I mentioned above, I used «Single Turn domain » subnodes, «Boundary Feed» and «Ground» , on a gap in the coil. I got also «Failed to find initial solution».

— I followed the «helmholtz-coil» model and I used the «Multi coil domain» node : I selected «Circular» coil type with 1 as a number of turns and I added a » Reference Edge» node which is the inner circular edge of the coil. Guess what? Yes, «Failed to find initial solution».

I’m starting to think it’s some kind of a bug in Comsol which occurs with circular coils in 3D’s time dependent simulation. Because I tested a linear vertical coil using one of these BCs and I got the simulation running perfectly.

But I really hope it’s not a bug. I hope it’s me missing something. And I’m desperately hoping for your experienced help. Please, tell me what’s wrong ! 🙁

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Multisim and Ultiboard

Modeling and Simulation occur error

Modeling and Simulation occur error

‎01-28-2010 06:30 AM — edited ‎01-28-2010 06:38 AM

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I have established a model about APEX PA78, but the simulation reports some error, please help me!

Spreadsheet view report is followed:

—— Checking SPICE netlist for PA78 — 2010-01-28 20:12:00 ——
SPICE Netlist Error in schematic RefDes ‘u2’, element ‘xu2′: Unexpected ’15’ found on subckt instance line — too many nodes or parameter value missing name.

SPICE Netlist Error in schematic RefDes ‘u2’, element ‘ ‘: Due to errors, the subckt instance ‘xu2’ has been omitted from the simulation

SPICE Netlist Error in schematic RefDes ‘u1’, element ‘xu1’: Unexpected ‘1’ found on subckt instance line — too many nodes or parameter value missing name.

SPICE Netlist Error in schematic RefDes ‘u1’, element ‘ ‘: Due to errors, the subckt instance ‘xu1’ has been omitted from the simulation

======= SPICE Netlist check completed, 4 error(s), 0 warning(s) =======

The accessory includes three files, they are:

PA78.TXT is the BERKELEY SPICE model about PA78 from

PA78U_B.pdf is data sheet about PA78 from

PA78.ms10 is a bridge-connected configuration, but PA78 itself don’t run a simulation.

Re: Modeling and Simulation occur error

‎01-28-2010 09:46 AM

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I found the problem with the netlist — the model only specifies 10 nodes:

.SUBCKT PA78_BERKELEY__TEST__3 7 6 1 2 12 4 8 11 10 3

but the component template is using 12:

x%p %tIL %tOUT %tCC- %t-VS %tNC1 %t-IN %t+IN %tCR+ %tNC2 %tCR- %tCC+ %t+VS %m

Either add the missing nodes to the definition, or remove them from the template so that the number of parameters matches.

Also, I noticed that the subcircuit is missing a .ENDS at the very end — you’ll need to add that as well.

Software Developer
National Instruments Electronics Workbench Group

Re: Modeling and Simulation occur error

‎01-28-2010 09:54 AM

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The simulation error in this case is telling you that there are too many pins for the subcircuit. The APEX PA78 subcircuit that you have uses 10 nodes, but the netlist that Multisim is trying to simulate has 12 nodes. It looks like there are two pins (pin 9 and pin 5) that aren’t supposed to be connected to anything, and shouldn’t be used in the simulation, but Multisim doesn’t know that they’re not supposed to be there and is adding unconnected simulation nodes for them.

To mark those pins as unused in the model, edit the component in your database, go to the model tab, and change the model nodes for the pins that aren’t used by the SPICE model to «NC» (Not Connected). It looks like the rest of the pins will need to be adjusted as well. Assuming I grabbed the right file from the links you provided, the subcircuit doesn’t use the pins in the same order as the component defines them. The .lib file for the PA78 notes that the first node that needs to be provided is +IN, the second node -IN, etc, which means that the model to pin mapping needs to map symbol pin «+IN» to Model node»1″, «-IN» to «2», «IL» to «3» and so on in the order they’re written in the documentation in the SPICE subcircuit you’re using (instead of the order in which they are numbered on the actual component).

After fixing up the pin mappings for the component in the database, you can use the «Update Circuit Components» command in the Tools menu to apply the fixes to the components already placed in your circuit.

回复： Modeling and Simulation occur error

‎01-29-2010 08:54 PM

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Thank AngelaS and clansing!

It’s very queer that Multisim must match the number of pins in sequence.
Even if Multisim is told that PA78 is 12 pin in component Wizard — Step

2 of 8,
whereas, the symbol of PA78 defines 10 pins for use, 5 and 9 is NC pins

not to define in Step 3,
as a result that Multisim only provides 10 pins in sequence so as that

pin mapping can’t skip to match pins in Step 6. for example 11 and 12

aren’t found to pick up in drop-down menu.

Now, I have add 5 and 9 NC pins in order to match model pins. According to AngelaS I also notice and add .ENDS at last of PA78 Spice, However, Spreadsheet view still reports error:

—— Checking SPICE netlist for PA78 —
——
SPICE Netlist Error in schematic RefDes », element ‘ ‘: Unmatched «.ENDS» statement

======= SPICE Netlist check completed, 1 error(s), 0 warning(s) =======

Please help me to debug, thank!

PA78 BERKELEY SPICE model still stay above.

PA78(modified and still error).ms11 stay this accessory.

Re: 回复： Modeling and Simulation occur error

‎02-01-2010 02:20 PM

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I’ll expand a little on what Angela said about the .ENDS, and then try to clear up the pins.

The SPICE model that you are using for the PA78 includes several subcircuits and models. Best practice for creating a component in Multisim is to have only a single .SUBCKT or .MODEL per component. The point of this is to make sure that any additional subcircuits or models are contained so that they don’t interfere with each other in the final netlist. The easiest way to fix this is to move the .ENDS for the main subcircuit to the end of the entire block — so instead of just adding the .ENDS at the end, you would need to also remove the first .ENDS line in the file. For this circuit, you probably don’t need to do that, however in general it’s a good idea to do it when making a component like this.

As for the pins, step 6 of the Component Wizard is asking you for the order that the pins will be used in the model. The (original) model you have only has 10 nodes, so it’s not a problem if you only have 10 pins there. If you have 12 pins on your symbol, and only 10 model nodes, then you just mark the two unused pins as «NC»(you can also add two «fake» pins to the .SUBCKT which is what you did, but you don’t have to).

For the rest of the pins, look at the .SUBCKT line and the comments just before it:

The comments telling you the pinout order are telling you the order that the pins must be listed when using the PA78 .SUBCKT. As you can see from the .SUBCKT line and comments, even though IL is pin 1 on the component, it actually needs to be listed third when using the .SUBCKT. That’s what Step 6 in the Component Wizard is asking you for. Step 6 lets you tell Multisim the order in which to use the pins. The comment tells you that +IN is model node 1, -IN is model node 2, IL is model node 3, etc, and then you tell Multisim this by setting the model node numbers

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Simulation error still occurs

Simscape™ simulations can stop before completion with one or more error messages. This section discusses generic error types and error-fixing strategies. You might find the previous section, How Simscape Simulation Works, useful for identifying and tracing errors.

If a simulation failed:

Review the model configuration. If your error message contains a list of blocks, look at these blocks first. Also look for:

Wrong connections — Verify that the model makes sense as a physical system. For example, look for actuators connected against each other, so that they try to move in opposite directions, or incorrect connections to reference nodes that prevent movement. In electrical circuits, verify polarity and connections to ground.

Wrong units — Simscape unit manager offers great flexibility in using physical units. However, you must exercise care in specifying the correct units, especially in the Simulink-PS Converter and PS-Simulink Converter blocks. Start analyzing the circuit by opening all the converter blocks and checking the correctness of specified units.

Try to simplify the circuit. Unnecessary circuit complexity is the most common cause of simulation errors.

Break the system into subsystems and test every unit until you are positive that the unit behaves as expected.

Build the system by gradually increasing its complexity.

It is recommended that you build, simulate, and test your model incrementally. Start with an idealized, simplified model of your system, simulate it, verify that it works the way you expected. Then incrementally make your model more realistic, factoring in effects such as friction loss, motor shaft compliance, hard stops, and the other things that describe real-world phenomena. Simulate and test your model at every incremental step. Use subsystems to capture the model hierarchy, and simulate and test your subsystems separately before testing the whole model configuration. This approach helps you keep your models well organized and makes it easier to troubleshoot them.

System Configuration Errors

Missing Solver Configuration Block

Each topologically distinct Simscape block diagram requires exactly one Solver Configuration block to be connected to it. The Solver Configuration block specifies the global environment information and provides parameters for the solver that your model needs before you can begin simulation.

If you get an error message about a missing Solver Configuration block, open the Simscape Utilities library and add the Solver Configuration block anywhere on the circuit.

Extra Fluid or Gas Properties Block

If your model contains hydraulic elements, each topologically distinct hydraulic circuit in a diagram requires a Custom Hydraulic Fluid block (or Hydraulic Fluid block, available with Simscape Fluids™ block libraries) to be connected to it. These blocks define the fluid properties that act as global parameters for all the blocks connected to the hydraulic circuit. If no hydraulic fluid block is attached to a loop, the hydraulic blocks in this loop use the default fluid. However, more than one hydraulic fluid block in a loop generates an error.

Similarly, more than one Thermal Liquid Settings (TL) block in a thermal liquid circuit, Two-Phase Fluid Properties (2P) block in a two-phase fluid circuit, or Gas Properties (G) block in a gas circuit generates an error.

If you get an error message about too many domain-specific global parameter blocks attached to the network, look for an extra Hydraulic Fluid block, Custom Hydraulic Fluid block, Thermal Liquid Settings (TL) block, Two-Phase Fluid Properties (2P) block, or Gas Properties (G) block and remove it.

Missing Reference Block

Simscape libraries contain domain-specific reference blocks, which represent reference points for the conserving ports of the appropriate type. For example, each topologically distinct electrical circuit must contain at least one Electrical Reference block, which represents connection to ground. Similarly, hydraulic conserving ports of all the blocks that are referenced to atmosphere (for example, suction ports of hydraulic pumps, or return ports of valves, cylinders, pipelines, if they are considered directly connected to atmosphere) must be connected to a Hydraulic Reference block, which represents connection to atmospheric pressure. Mechanical translational ports that are rigidly clamped to the frame (ground) must be connected to a Mechanical Translational Reference block, and so on.

If you get an error message about a missing reference block, or node, check your system configuration and add the appropriate reference block based on the rules described above. The missing reference node diagnostic messages include information about the particular block and variable that needs a reference node. This is especially helpful when multiple domains are involved in the model. For more information and examples of best modeling practices, see Grounding Rules.

Basic Errors in Physical System Representation

Physical systems are represented in the Simscape modeling environment as Physical Networks according to the Kirchhoff’s generalized circuit laws. Certain model configurations violate these laws and are therefore illegal. There are two broad violations:

Sources of domain-specific Across variable connected in parallel (for example, voltage sources, hydraulic pressure sources, or velocity sources)

Sources of domain-specific Through variable connected in series (for example, electric current sources, hydraulic flow rate sources, force or torque sources)

These configurations are impossible in the real world and illegal theoretically. If your model contains such a configuration, upon simulation the solver issues an error followed by a list of blocks, as shown in the following example.

Example. The model shown in the following illustration contains two Ideal Translational Velocity Sources connected in parallel. This produces a loop of independent velocity sources, and the solver cannot construct a consistent system of equations for the circuit.

When you try to simulate the model, the solver issues an error message with links to the Ideal Translational Velocity Source and Ideal Translational Velocity Source1 blocks. To fix the circuit, you can either replace the two velocity sources by a single Ideal Translational Velocity Source block, or add a Translational Damper block between them.

Numerical Simulation Issues

Numerical simulation issues can be either a result of certain circuit configurations or of parameter discontinuities.

Dependent Dynamic States

Certain circuit configurations can result in dependent dynamic states, or the so-called higher-index differential algebraic equations (DAEs). Simscape solver can handle dependencies among dynamic states that are linear in the states and independent of time and inputs to the system. For example, capacitors connected in parallel or inductors connected in series will not cause any problems. Other circuit configurations with dependent dynamic states, in certain cases, may slow down the simulation or lead to an error when the solver fails to initialize.

Problems may occur when dynamic states have a nonlinear algebraic relationship. An example is two inertias connected by a nonlinear gear constraint, such as an elliptical gear. In case of simulation failure, the Simscape solver may be able to identify the components involved, and provide an error message with links to the blocks and to the equations within each block.

Parameter Discontinuities

Nonlinear parameters, dependent on time or other variables, may also lead to numerical simulation issues as a result of parameter discontinuity. These issues usually manifest themselves at the transient initialization stage (see Transient Simulation Issues).

Initial Conditions Solve Failure

The initial conditions solve, which solves for all system variables (with initial conditions specified on some system variables), may fail. This has several possible causes:

System configuration error. In this case, the Simulation Diagnostics window usually contains additional, more specific, error messages, such as a missing reference node, or a warning about the component equations, followed by a list of components involved. See System Configuration Errors for more information.

Dependent dynamic state. In this case, the Simulation Diagnostics window also may contain additional, more specific, error messages, such as a warning about the component equations, followed by a list of components involved. See Dependent Dynamic States for more information.

The residual tolerance may be too tight to produce a consistent solution to the algebraic constraints at the beginning of simulation. You can try to increase the Consistency Tolerance parameter value (that is, relax the tolerance) in the Solver Configuration block.

If the Simulation Diagnostics window has other, more specific, error messages, address them first and try rerunning the simulation. See also Troubleshooting Tips and Techniques.

Transient Simulation Issues

Transient initialization happens at the beginning of simulation (after computing the initial conditions) or after a subsequent event, such as a discontinuity (for example, when a hard stop hits the stop). It is performed by fixing all dynamic variables and solving for algebraic variables and derivatives of dynamic variables. The goal of transient initialization is to provide a consistent set of initial conditions for the next transient solve step.

Transient Initialization Not Converging

Error messages stating that transient initialization failed to converge, or that a set of consistent initial conditions could not be generated, indicate transient initialization issues. They can be a result of parameter discontinuity. Review your model to find the possible sources of discontinuity. See also Troubleshooting Tips and Techniques.

You can also try to decrease the Consistency Tolerance parameter value (that is, tighten the tolerance) in the Solver Configuration block.

Step-Size-Related Errors — Dependent States — High Stiffness

A typical step-size-related error message may state that the system is unable to reduce the step size without violating the minimum step size for a certain number of consecutive times. This error message indicates numerical difficulties in solving the Differential Algebraic Equations (DAEs) for the model. This might be caused by dependent dynamic states (higher-index DAEs) or by the high stiffness of the system. You can try the following:

Tighten the solver tolerance (decrease the Relative Tolerance parameter value in the Configuration Parameters dialog box)

Specify a value, other than auto , for the Absolute Tolerance parameter in the Configuration Parameters dialog box. Experiment with this parameter value.

Tighten the residual tolerance (decrease the Consistency Tolerance parameter value in the Solver Configuration block)

Increase the value of the Number of consecutive min step size violations allowed parameter in the Configuration Parameters dialog box (set it to a value greater than the number of consecutive step size violations given in the error message)

Review the model configuration and try to simplify the circuit, or add small parasitic terms to your circuit to avoid dependent dynamic states. For more information, see Numerical Simulation Issues.

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Похожие слова: simulation error

Синонимы & Антонимы: не найдено

Если вы ищете как runtime error исправить — вы попали по адресу.

Причин появления таковой может быть огромное множество.

Чаще всего причина состоит в том, что выходит новая версия того или иного приложения/игры и она устанавливается прямо поверх старой.

Хотя это далеко не единственная ситуация, которая может вызвать ее появление.

После того, как вы нажимаете на единственную кнопку в окне ошибки, оно просто закрывается и программа также перестает работать.

Бывает, что она все же продолжает работать, но в ней невозможно ничего сохранить. В любом случае, есть несколько способов исправить ее.

Как выглядит ошибка

Способ №1. CCleaner

Самое простое решение заключается в том, чтобы воспользоваться программой для чистки реестра. Как это работает?

Все просто – чистильщик реестра, собственно, и предназначен для того, чтобы исправлять всевозможные проблемы, вроде той, которую рассматриваем мы, систематизировать файлы и добавлять то, чего недостает ему для нормальной работы.

Лучшей по праву считается CCleaner, хотя вы можете воспользоваться и другой.

Чтобы использовать ее, сделайте вот что:

1. Скачайте (вот ссылка на бесплатную) и установите программу.
2. Запустите. Перейдите на вкладку «Реестр» на панели слева.
3. В разделе «Целостность» поставьте галочки на всех возможных пунктах – никто не знает, в чем именно проблема.
4. Нажмите кнопку «Поиск проблем». Когда этот процесс закончится, нажмите кнопку «Исправить…».

Использование

1. Подождите, пока приложение исправит все проблемы. Перезагрузите компьютер.

После этого runtime error должен перестать появляться. Если нет, переходим к следующему решению.

Способ №2. DirectX

Вполне вероятно, что ее появление вызывают какие-то проблемы с DirectX. Возможно, какие-то файлы исполняемых библиотек были повреждены или же существующие библиотеки банально устарели.

В любом случае, лучше всего просто установить наиболее актуальные варианты и, опять же, перезагрузить компьютер.

Для этого зайдите на сайт Microsoft, на страницу с возможностью скачать DirectX. Запустите скачанный файл и выполните все действия, подразумевающие установку исполняемых библиотек.

Здесь нет никаких особых рекомендаций – обычная.

Страница загрузки DirectX

Если после установки и перезагрузки компьютера ошибка не исчезла, идем дальше.

Способ №3. Visual C++

О распространяемом пакете Visual C++ в контексте рассматриваемой проблемы можно скачать то же самое, что и о библиотеках DirectX.

Возможно, какие-то файлы были повреждены или версия устарела.

Бывают в данном случае и другие ситуации, когда установленная C++ попросту не подходит для вашей операционной системы.

Ниже приведена таблица с вариантами, которые подходят для разных версий ОС.

Так вот, в зависимости от того, какая у вас ОС, вам следует скачать и инсталировать на свой компьютер C++2008 (64-бит, 32-бит), C++2010 (64-бит, 32-бит) или же C++2015 обновление 3.

Это наиболее актуальная версия по состоянию на июнь 2017 года. В будущем выйдут новые, поэтому следите за новостями на официальном сайте Microsoft.

Скачивание происходит одинаково – выбираем язык распространяемого компонента и жмем кнопку «Скачать». После этого останется запустить загруженный файл.

После этого перезагрузите компьютер.

Страница загрузки Visual C++

Способ №4. Microsoft .NET Framework

Здесь все то же самое – Microsoft .NET Framework тоже может вызывать рассматриваемую проблему из-за отсутствия каких-то собственных файлов. И этот компонент также нужно скачать и установить.

Но есть определенный, правильный порядок ее инсталяции:

Сначала необходимо инсталируйте версию 2.0 (вот ссылка). Попробуйте запустить программу, в которой раньше возникала проблема, если она не исчезла, устанавливайте дальше.

После этого 3.0 (скачать).

Если не помогает, 4.0 (ссылка).

Наконец, если у вас Windows Vista SP2, 7 SP1, 8, 8.1, Server 2008 SP2, Server 2008 R2 SP1, Server 2012 или Server 2012 R2, установите 4.6.2 (скачать).

Скачивание происходит точно так же, как и в случае с пакетами Visual C++.

Если ничего из этого не помогает, значит, случился сбой самой операционной системы. Пригласите на дом специалиста или сдайте компьютер в сервисный центр, если это возможно.

В крайнем случае, сделайте откат системы или вовсе переустановите ее.

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