The dual-stage matching system can match users with the most suitable dual-stage compression system according to the different working conditions and different cooling capacity requirements of users. According to the characteristics of the system load, the system intermediate pressure and the model and number of high and low pressure compressors can be selected flexibly and freely, thereby achieving the purpose of improving the energy efficiency of the system.
●It can be applied in the dual-stage matching system at both the low temperature load and the high temperature load. The low temperature load is sucked through the low pressure compressor while the medium and high temperature load is fed through the medium pressure pipe. In this way, both the high temperature storehouse and the low temperature freezing house are both realized on one unit. And the dual-stage matching system is especially suitable for quick-freezing projects. The early cooling of the cold store reflects a high temperature load, and the late freezing reflects a low temperature load. The suction of the high-pressure compressor on the dual-stage system can be switched between the return air and the medium-pressure pipe. In the early cooling stage, only the high-pressure compressor is needed to cool down the system without the need of the suction pressure limiting device; when the temperature of the storehouse reaches a certain level, the low-pressure compressor is started for dual-stage compression cooling. In this way, the cooling speed of the entire system will be significantly higher than the traditional single-stage compression system and the single-unit dual-stage system, and it will also save more energies.