Electric drive systems will play an important role in the development of future automobile architectures. The electrification allows a diversification of energy sources and offers great opportunities for an environmentally friendly expansion in the automotive industry. However, the electric drives are a challenge for the manufacturers. The electrical powertrain can not only be exposed to interferences, it may also emit interferences into components and communication cables in the vicinity. These can be a high risk for the drive system and for the passengers. To study the electrical powertrain more in detail and thus avoid these interferences, simulations are a useful tool. This paper presents different types of simulations of electrical powertrains for transportation systems. As a main aspect, the interference coupling of the High Voltage cables (HV-cables) of the electrical powertrain to nearby communication cables is studied using field simulation based on the method of moments and also network simulation with SPICE. The results obtained through simulations are compared with those from measurements in an anechoic chamber. A brief summary on the measurement setup and the measurement procedure is also given.