An electrical power converter comprising: - first AC voltage terminals (U1, V1, W1); - first DC voltage terminals (P, M); - a converter cell series unit (20 PU, 20 PV, 20 PW, 20 MU, 20 MV, 20 MW) composed of one or more converter cells connected in series between the first AC voltage terminals (U1, V1, W1) and the first DC voltage terminals (P,M), each converter cell including a semiconductor element and a capacitor; - a first inductance connected in series to the converter cell series unit (20 MU, 20 MV, 20 MW) between, of the first DC voltage terminals (P,M), one of the first DC voltage terminals at the lowest potential with respect to a ground, and the first AC voltage terminals (U1,V1,W1); - a second inductance connected in series to the converter cell series unit (20 PU, 20 PV, 20 PW) and having a smaller inductance value than the first inductance, between the other first DC voltage terminal and the first AC voltage terminals (U1, V1, W1), - second AC voltage terminals (U2, V2; W2); - second DC voltage terminals (M, N), wherein a negative terminal of the first DC voltage terminals and a positive terminal of the second DC voltage terminals are connected and regarded as a neutral point, wherein the neutral point is present at a potential closer to a ground than the first and second AC voltage terminals (U1-W1, U2-W2) and positive and negative DC voltage terminals (P, N) are; the electrical power converter further comprising: - converter cell series units (30 MU, 30 MV, 30 MW, 30 NU, 30 NV, 30 NW) provided between the second AC voltage terminals (U2, V2, W2) and the neutral point, and between the second AC voltage terminals (U2, V2, W2) and the negative terminal of the second DC voltage terminals, - a third inductance connected in series to the converter cell series unit (30 MU, 30 MV, 30 MW), between the second AC voltage terminals (U2, V2, W2) and the neutral point; and - a fourth inductance connected in series to the converter cell series unit (30 MU, 30 MV, 30 MW) and having a smaller inductance value than the third inductance between the second AC voltage terminals (U2, V2, W2) and the negative terminal of the second DC voltage terminals, wherein the first AC voltage terminals (U1, V1, W1) and the second AC voltage terminals (U2,V2,W2) are connected in parallel to each other via one or more transformers (401, 402). - first AC voltage terminals (U1, V1, W1); - first DC voltage terminals (P, M); - a converter cell series unit (20 PU, 20 PV, 20 PW, 20 MU, 20 MV, 20 MW) composed of one or more converter cells connected in series between the first AC voltage terminals (U1, V1, W1) and the first DC voltage terminals (P,M), each converter cell including a semiconductor element and a capacitor; - a first inductance connected in series to the converter cell series unit (20 MU, 20 MV, 20 MW) between, of the first DC voltage terminals (P,M), one of the first DC voltage terminals at the lowest potential with respect to a ground, and the first AC voltage terminals (U1,V1,W1); - a second inductance connected in series to the converter cell series unit (20 PU, 20 PV, 20 PW) and having a smaller inductance value than the first inductance, between the other first DC voltage terminal and the first AC voltage terminals (U1, V1, W1), - second AC voltage terminals (U2, V2; W2); - second DC voltage terminals (M, N), wherein a negative terminal of the first DC voltage terminals and a positive terminal of the second DC voltage terminals are connected and regarded as a neutral point, wherein the neutral point is present at a potential closer to a ground than the first and second AC voltage terminals (U1-W1, U2-W2) and positive and negative DC voltage terminals (P, N) are; - converter cell series units (30 MU, 30 MV, 30 MW, 30 NU, 30 NV, 30 NW) provided between the second AC voltage terminals (U2, V2, W2) and the neutral point, and between the second AC voltage terminals (U2, V2, W2) and the negative terminal of the second DC voltage terminals, - a third inductance connected in series to the converter cell series unit (30 MU, 30 MV, 30 MW), between the second AC voltage terminals (U2, V2, W2) and the neutral point; and - a fourth inductance connected in series to the converter cell series unit (30 MU, 30 MV, 30 MW) and having a smaller inductance value than the third inductance between the second AC voltage terminals (U2, V2, W2) and the negative terminal of the second DC voltage terminals,