Introduction. Short-term peak loads of machines and mechanisms create the need to accumulate mechanical energy for its subsequent pulsed use. This is quite relevant, for example, for tractors at the initial stage of towing heavy trailers. The use of a mechanical energy accumulator will reduce the power of the tractor engine and expand its functionality.Target. Development of a mathematical model of a mechanical energy accumulator.Research methods. The mechanical energy accumulator can be made in the form of a direct current electric machine or a valve machine, on the shaft of which a superflywheel is attached. When a machine is connected to a power source, a non-stationary process occurs, described by two differential equations: one for mechanical quantities, the other for electrical ones. Solutions of differential equations repeat the relationships for charging and discharging an electric capacitor.Results. From the resulting formulas it follows that for an electrical circuit, the mechanical energy accumulator in question is indistinguishable from an electrical capacitor. It follows from this that in this case we can talk about artificial electrical capacitance. In addition, artificial electrical resistance arises (which is not related to the resistivity, length and cross-sectional area of the conductors). In connection with the above, a mechanical energy accumulator can be interpreted as an artificial electric capacitor, which stores not the energy of the electric field, but the kinetic energy of rotation of the superflywheel.Conclusion. There are superflywheel designs that can store significant kinetic energy. Even the possibility of installing them on passenger vehicles was studied. In this sense, massive tractors have an undeniable advantage, since the increase in weight is not only not problematic for them, but in some cases it is desirable.