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New behavioral capacitor model: 

- Replace E source by G source with parallel resistor to improve
  convergence.
- Add parallel resistor to avoid floating nodes
- Reduce refecrence C to 1u (and thus the max. current).
This commit is contained in:
Holger Vogt 2026-06-12 16:43:58 +02:00
parent 63d45e81ab
commit 62f0b2d8cc
1 changed files with 34 additions and 6 deletions
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40
src/frontend/inpcom.c
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@ -6926,7 +6926,13 @@ static void inp_compat(struct card *card)
ckt_array[2] = tprintf("b%s 0 %s_int1 i = (%s) "
"%s reciproctc=1",
title_tok, title_tok, equation, tcrstr);
// comment out current variable capacitor line
*(card->line) = '*';
for (i = 0; i < 3; i++) {
card = insert_new_line(card, ckt_array[i], (int)i + 1, currlinenumber, card->linesource);
}
} else { /* capacitance formulation */
#if (0)
// Exxx n-aux 0 n2 n1 1
ckt_array[0] = tprintf("e%s %s_int1 0 %s %s %s", title_tok,
title_tok, node2, node1, mstr);
@ -6936,15 +6942,37 @@ static void inp_compat(struct card *card)
ckt_array[2] = tprintf("b%s %s %s i = i(e%s) * (%s) "
"%s reciproctc=1",
title_tok, node1, node2, title_tok, equation, tcrstr);
// comment out current variable capacitor line
*(card->line) = '*';
for (i = 0; i < 3; i++) {
card = insert_new_line(card, ckt_array[i], (int)i + 1, currlinenumber, card->linesource);
}
#else
// Gxxx n-aux 0 n2 n1 1e9
ckt_array[0] = tprintf("g%s %s_int1 0 %s %s %se9", title_tok,
title_tok, node2, node1, mstr);
// Rxxx n-aux 0 1e-9 ; generate voltage from injected current by Gxxx
ckt_array[1] = tprintf("r%s %s_int1 0 1e-9", title_tok,title_tok);
// Cxxx n-aux1 n-aux2 1e-6
ckt_array[2] = tprintf("c%s %s_int1 %s_int2 1e-6", title_tok, title_tok, title_tok);
// Vxxx n-aux2 0 0 ; measure current in Cxxx
ckt_array[3] = tprintf("v%s %s_int2 0 0", title_tok, title_tok);
// Rxxxpar n2 n1 1e15 ; generally avoid floating nodes
ckt_array[4] = tprintf("r%spar %s %s 1e15", title_tok, node2, node1);
// Bxxx n1 n2 I = 1e6 * i(Vxxx) * equation
ckt_array[5] = tprintf("b%s %s %s i = 1e6 * i(v%s) * (%s) "
"%s reciproctc=1",
title_tok, node1, node2, title_tok, equation, tcrstr);
// comment out current variable capacitor line
*(card->line) = '*';
// insert new B source line immediately after current line
for (i = 0; i < 6; i++) {
card = insert_new_line(card, ckt_array[i], (int)i + 1, currlinenumber, card->linesource);
}
#endif
}
tfree(tcrstr);
tfree(mstr);
// comment out current variable capacitor line
*(card->line) = '*';
// insert new B source line immediately after current line
for (i = 0; i < 3; i++) {
card = insert_new_line(card, ckt_array[i], (int)i + 1, currlinenumber, card->linesource);
}
tfree(title_tok);
tfree(node1);