"单节机动有轨车" can be translated as "single-section motorized tram" or "single-car motorized tramcar" in English.
"Single-section" or "single-car" emphasizes that it consists of only one section or car.
"Motorized" indicates that it is powered by a motor.
"Tram" or "tramcar" refers to a type of rail vehicle that runs on tracks, typically in urban areas.