In one aspect, an arrangement for cooling of an electrical machine is provided. The arrangement includes a rotor and a stator of the electrical machine, while an air-gap is between the rotor and the stator. The electrical machine includes an air-cooling-arrangement, which circulates air inside the electrical machine. The electrical machine includes a liquid-cooling-arrangement, which circulates cooling-liquid inside the electrical machine. The air-cooling arrangement and the liquid-cooling-arrangement are connected by an air-to-liquid heat-exchanger, which is applied to transport heat out from the electrical machine by the cooling-liquid.