• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Singular Matrix error node on LTSpice

Status
Not open for further replies.

Stephane38

New Member
Hi,

I have designed some piezo harvested circuits designed in LTspice as attached.
The first one is a simple case, the piezo is modelised by the current source I1 and the C1 capacitor. Then there is an diode bridge and finally a storage capacitor C2.

In the second design, I added a sw which has to closed when the I1 current reach 0A (SSDC).
When i want to run my design with an 0.025A, it poped up with "Singular Matrix: check node entre- Iteration no4"
BUT when I change to a 0.024A, there is no pb and I have the results I want.

Then the last circuit arrives, it's the same with an inductor (SSDCI).
It poped up with "Singular Matrix: check node n001 Iteration no4"
So there is a pb with C1 node. When I add a node to n001, the problem is solved but that isn't the results I want to use the diode bridge rectifier (like the first circuit but with an switch).

If someone can help me please ?:(
 

Attachments

alec_t

Well-Known Member
Most Helpful Member
Use 'real' diodes instead of the default generic ones and the sims should run ok.
Welcome to ETO!
 

eTech

Well-Known Member
Hi,

I have designed some piezo harvested circuits designed in LTspice as attached.
The first one is a simple case, the piezo is modelised by the current source I1 and the C1 capacitor. Then there is an diode bridge and finally a storage capacitor C2.

In the second design, I added a sw which has to closed when the I1 current reach 0A (SSDC).
When i want to run my design with an 0.025A, it poped up with "Singular Matrix: check node entre- Iteration no4"
BUT when I change to a 0.024A, there is no pb and I have the results I want.

Then the last circuit arrives, it's the same with an inductor (SSDCI).
It poped up with "Singular Matrix: check node n001 Iteration no4"
So there is a pb with C1 node. When I add a node to n001, the problem is solved but that isn't the results I want to use the diode bridge rectifier (like the first circuit but with an switch).

If someone can help me please ?:(
Hi

Use the "startup" option with the tran statement, like this:

tran 2 startup

or check the checkbox "Start external DC supply voltages at 0v:".

If you don't do this then the simulator expects the user to set all initial operating conditions.

After I checked this box all ran with no issues.

eT
 

Stephane38

New Member
Use 'real' diodes instead of the default generic ones and the sims should run ok.
Welcome to ETO!
Thanks a lot it is working now!

Hi

Use the "startup" option with the tran statement, like this:

tran 2 startup

or check the checkbox "Start external DC supply voltages at 0v:".

If you don't do this then the simulator expects the user to set all initial operating conditions.

After I checked this box all ran with no issues.

eT
Hey, it didn't fixed my pb but it is good to know!

Thanks guys
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top