Two-stage refrigerant compressor and operation method thereof

A two-stage refrigerant compressor, comprising:

• a housing (1), comprising an inner space divided into an air suction channel (11), a first compressing room (12), an electric machine room (13), a second compressing room (14) and an air discharge channel (15) sequentially defined and communicating with each other;
• a first compressor module (2), comprising a pair of first screw rods (21) disposed in the first compressing room (12) and mutually engaged, and a first motor (22) disposed in the electric machine room (13) and configured to drive one of the first screw rods (21) to rotate, wherein a first contact line (L1) is defined by the pair of first screw rods (21);
• a second compressor module (3), comprising a pair of second screw rods (31) disposed in the second compressing room (14) and mutually engaged, and a second motor (32) disposed in the electric machine room (13) and configured to drive one of the second screw rods (31) to rotate, wherein a second contact line (L2) is defined by the pair of second screw rods (31);
• an adjustment mechanism (4), comprising a first slide valve (41) moveably disposed corresponding to the first contact line (L1) and a second slide valve (42) moveably disposed corresponding to the second contact line (L2);
• a pressure sensing set (5), comprising at least one middle pressure sensor (51) disposed in the electric machine room (13) to acquire a current middle pressure;
• and
• a processor, connected to the first motor (22), the second motor (32), the first slide valve (41), the second slide valve (42) and the at least one middle pressure sensor (51), and configured to receive data of the current middle pressure, control a rotating speed of the first motor (22) and a rotating speed of the second motor (32), and control a location of the first slide valve (41) and a location of second slide valve (42);
• wherein, the pressure sensing set (5) further comprises an air suction pressure sensor (52) and an air discharge pressure sensor (53), the air suction pressure sensor (52) is disposed in the air suction channel (11) to acquire an air suction pressure, the air discharge pressure sensor (53) is disposed in the air discharge channel (15) to acquire an air discharge pressure, the processor is connected to the air suction pressure sensor (52) and the air discharge pressure sensor (53), and the processor is configured to receive data of the air suction pressure and the air discharge pressure.