def test_two_wire_capacitance_bad_method():
rw = 1e-3
s = 10e-3
wires = [Wire(-0.5 * s, 0, rw)]
ref = Wire(0.5 * s, 0, rw)
pair = mtl.WireMtl(wires, ref)
with pytest.raises(Exception):
pair.capacitance(method='junk')
def test_two_wire_inductance():
rw = 7.5
s = 50
wires = [Wire(-0.5 * s, 0, rw)]
ref = Wire(0.5 * s, 0, rw)
pair = mtl.WireMtl(wires, ref)
L = mtl.wire_inductance(s, rw)
assert pair.inductance()[[0]] == approx(L, rel=0.02)
def test_two_wire_capacitance():
rw = 7.5
s = 50
wires = [Wire(-0.5 * s, 0, rw)]
ref = Wire(0.5 * s, 0, rw)
pair = mtl.WireMtl(wires, ref)
C = mtl.wire_capacitance(s, rw)
assert pair.capacitance()[[0]] == approx(C, rel=0.02, abs=1e-14)
def test_two_wire_capacitance_fdm_near():
rw = 1e-3
s = 3e-3
wires = [Wire(-0.5 * s, 0, rw)]
ref = Wire(0.5 * s, 0, rw)
pair = mtl.WireMtl(wires, ref)
expected = mtl.wire_capacitance(s, rw)
C = pair.capacitance(method='fdm', fdm_params={'dx': rw / 10})
assert C == approx(expected, rel=0.05, abs=0.1e-12)
def test_two_wire_capacitance_fdm_diagonal():
rw = 1e-3
x2 = y2 = 6e-3
wires = [Wire(0, 0, rw)]
ref = Wire(x2, y2, rw)
pair = mtl.WireMtl(wires, ref)
expected = pair.capacitance(method='ana')
C = pair.capacitance(method='fdm')
assert C == approx(expected, rel=0.05, abs=0.1e-12)
def test_two_wire_capacitance_fdm():
rw = 1e-3
s = 8e-3
wires = [Wire(-0.5 * s, 0, rw)]
ref = Wire(0.5 * s, 0, rw)
pair = mtl.WireMtl(wires, ref)
expected = pair.capacitance(method='ana')
C = pair.capacitance(method='fdm')
assert C == approx(expected, rel=0.05, abs=0.1e-12)
def test_two_wire_inductance_diagonal():
rw = 7.5
s = 50
x2 = y2 = s / np.sqrt(2)
wires = [Wire(0, 0, rw)]
ref = Wire(x2, y2, rw)
pair = mtl.WireMtl(wires, ref)
L = mtl.wire_inductance(s, rw)
assert pair.inductance()[[0]] == approx(L, rel=0.02)
def test_two_wire_capacitance_diagonal():
rw = 7.5
s = 50
x2 = y2 = s / np.sqrt(2)
wires = [Wire(0, 0, rw)]
ref = Wire(x2, y2, rw)
pair = mtl.WireMtl(wires, ref)
C = mtl.wire_capacitance(s, rw)
assert pair.capacitance()[[0]] == approx(C, rel=0.02, abs=1e-14)
def test_three_wire_inductance():
# Paul MTL P5.4
rw = 7.5
s = 50
wires = [Wire(s, 0, rw), Wire(-s, 0, rw)]
ref = Wire(0, 0, rw)
bus = mtl.WireMtl(wires, ref)
L = bus.inductance()
expected = np.array([[0.759, 0.241], [0.241, 0.759]]) * 1e-6
assert L == approx(expected, rel=0.001)
def test_three_wire_capacitance():
# Paul MTL P5.4
rw = 7.5
s = 50
wires = [Wire(s, 0, rw), Wire(-s, 0, rw)]
ref = Wire(0, 0, rw)
bus = mtl.WireMtl(wires, ref)
C = bus.capacitance()
expected = np.array([[16.3, -5.17], [-5.17, 16.3]]) * 1e-12
assert C == approx(expected, rel=0.001, abs=1e-14)
def test_one_wire_capacitance_shield():
rw = 0.5e-3
rs = 4e-3
er = 5.2
wires = [Wire(0, 0, rw)]
ref = Shield(rs)
cable = mtl.WireMtl(wires, ref, er)
C = cable.capacitance()
expected = coax.capacitance(rw, rs, er)
assert C == approx(expected, rel=0.001, abs=1e-14)
def test_two_wire_capacitance_shield():
# Paul MTL P5.11
rw = 0.1905e-3
s = 4 * rw
rs = 4 * rw
wires = [Wire(-0.5 * s, 0, rw), Wire(0.5 * s, 0, rw)]
ref = Shield(rs)
pair = mtl.WireMtl(wires, ref)
C = pair.capacitance()
expected = np.array([[52.8, -10.73], [-10.73, 52.8]]) * 1e-12
assert C == approx(expected, rel=0.001, abs=1e-14)
def test_two_wire_inductance_shield():
# Paul MTL P5.10
rw = 0.1905e-3
s = 4 * rw
rs = 4 * rw
wires = [Wire(-0.5 * s, 0, rw), Wire(0.5 * s, 0, rw)]
ref = Shield(rs)
pair = mtl.WireMtl(wires, ref)
L = pair.inductance()
expected = np.array([[0.2197, 0.0446], [0.0446, 0.2197]]) * 1e-6
assert L == approx(expected, rel=0.001)
def test_two_wire_capacitance_plane():
# Paul MTL P5.7
rw = 0.04064
s = 2
h = 2
wires = [Wire(-0.5 * s, h, rw), Wire(0.5 * s, h, rw)]
ref = Plane()
pair = mtl.WireMtl(wires, ref)
C = pair.capacitance()
expected = np.array([[12.5, -2.19], [-2.19, 12.5]]) * 1e-12
assert C == approx(expected, rel=0.001, abs=1e-14)
def test_two_wire_inductance_plane():
# Paul MTL P5.7
rw = 0.04064
s = 2
h = 2
wires = [Wire(-0.5 * s, h, rw), Wire(0.5 * s, h, rw)]
ref = Plane()
pair = mtl.WireMtl(wires, ref)
L = pair.inductance()
expected = np.array([[0.918, 0.161], [0.161, 0.918]]) * 1e-6
assert L == approx(expected, rel=0.001)
def test_two_wire_capacitance_fdm_rw2():
rw1 = 1e-3
rw2 = 2e-3
s = 20e-3
wires = [Wire(-0.5 * s, 0, rw1)]
ref = Wire(0.5 * s, 0, rw2)
pair = mtl.WireMtl(wires, ref)
expected = pair.capacitance(method='ana')
print(expected)
C = pair.capacitance(method='fdm')
assert C == approx(expected, rel=0.05, abs=0.1e-12)
def test_empty_list():
with pytest.raises(ValueError):
mtl.WireMtl([], Plane())
def test_bad_wire():
with pytest.raises(TypeError):
mtl.WireMtl([Plane()], Plane())
def test_bad_ref():
with pytest.raises(TypeError):
mtl.WireMtl([Wire(0, 0, 0.5)], 'Ref!')