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From: Cyril on 19 Mar 2010 11:14
Hi,

I try to do the simulation of an hydraulic system with SimHydraulics.
When i launch the simulation, I have got this error :
"Dynamic states at start of simulation are not consistent. Setting all dynamic state initial conditions to zero may fix this problem."

But, i don't know what to do.

Could you help me ?
How could I send to you my Simulink model with this website ?

Regards,

Cyril
From: Cyril on 20 Mar 2010 05:10
"Cyril " <cyrstr(a)gmail.com> wrote in message <ho04bt$psi$1(a)fred.mathworks.com>...
> Hi,
>
> I try to do the simulation of an hydraulic system with SimHydraulics.
> When i launch the simulation, I have got this error :
> "Dynamic states at start of simulation are not consistent. Setting all dynamic state initial conditions to zero may fix this problem."
>
> But, i don't know what to do.
>
> Could you help me ?
> How could I send to you my Simulink model with this website ?
>
> Regards,
>
> Cyril

There is the mdl file : http://files.me.com/straub.cyril/9qs2d7

I need help, please.

Cyril
From: Arnaud Miege on 6 Apr 2010 10:54
"Cyril " <cyrstr(a)gmail.com> wrote in message <ho23de$3tq$1(a)fred.mathworks.com>...
> "Cyril " <cyrstr(a)gmail.com> wrote in message <ho04bt$psi$1(a)fred.mathworks.com>...
> > Hi,
> >
> > I try to do the simulation of an hydraulic system with SimHydraulics.
> > When i launch the simulation, I have got this error :
> > "Dynamic states at start of simulation are not consistent. Setting all dynamic state initial conditions to zero may fix this problem."
> >
> > But, i don't know what to do.
> >
> > Could you help me ?
> > How could I send to you my Simulink model with this website ?
> >
> > Regards,
> >
> > Cyril
>
> There is the mdl file : http://files.me.com/straub.cyril/9qs2d7
>
> I need help, please.
>
> Cyril

The error is because you have connected the gas-charged accumulator directly to the hydraulic cylinder. Both blocks set initial conditions for the pressure (0 for each chamber in cylinder, and variable in the accumulator depending on the initial volume parameter). Those two initial conditions were inconsistent in your model. To work around this, insert either a small orifice, a small linear hydraulic resistance or a hydraulic pipeline block between the cylinder and accumulator. I have tried it and it works.

There's one other thing that looks strange in your model, although it doesn't cause it to error out. The second cylinder has both chambers connected to port A of the 4-way directional valve, which doesn't really make sense to me. Is that correct?

HTH,

Arnaud
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