A temperature variation compensator comprises a fixed plate, movable pulleys, a movable pulley bracket, fixed pulleys, a fixed pulley bracket, a collapsing-expanding cylinder, a sliding rod and a stay cord; the stay cord penetrates among the movable pulleys and the fixed pulleys in a reciprocating mode alternately, a piston of the collapsing-expanding cylinder is fixedly connected with the fixed pulley bracket, and a cylinder body of the collapsing-expanding cylinder is fixedly connected with the movable pulley bracket; fluid is arranged inside the cylinder of the collapsing-expanding cylinder and has the heat expansion and cold contraction properties, and fluid materials are subjected to water removal. Electrical equipment, a power grid installation facility and a power grid system are each provided with the temperature variation compensator. The temperature variation compensator is simple in structure, low in cost, long in service life, easy to achieve, simple and easy to use, energy is not needed, and the phenomenon that the height and tensile force of a cable are constant can be achieved.