Abstract: The invention relates to an electric vehicle cabin heating system and a control method. The system comprises a first refrigerant circuit and a second refrigerant circuit that are connected in parallel, wherein the circuits each comprise a gas-liquid separator and a compressor that are connected in series; the first refrigerant circuit further comprises a first expansion unit; the second refrigerant circuit further comprises a second expansion unit and a condenser; and the first expansion unit is connected to the second expansion unit and the condenser in parallel. Thus, rapid cabin heating and stable heating capacity are achieved, the dependence on a heater is eliminated, and an air-conditioning system is simplified.

Abstract: The present invention relates to a fluidized bed reactor, comprising a reaction tube, a distributor and a heating device, the reaction tube and the distributor at the bottom of the reaction tube composing a closed space, the distributor comprising a gas inlet and a product outlet, and the reaction tube comprising a tail gas outlet and a seed inlet at the top or upper part respectively, characterized in that the reaction tube comprises a reaction inner tube and a reaction outer tube, and the heating device is an induction heating device placed within a hollow cavity formed between the external wall of the reaction inner tube and the internal wall of the reaction outer tube, wherein the hollow cavity is filled with hydrogen, nitrogen or inert gas for protection, and is able to maintain a pressure of about 0.01 to about 5 MPa; and also to a process of producing high purity granular polysilicon using the reactor.

Abstract: The present invention relates to a fluidized bed reactor, comprising a reaction tube, a distributor and a heating device, the reaction tube and the distributor at the bottom of the reaction tube composing a closed space, the distributor comprising a gas inlet and a product outlet, and the reaction tube comprising a tail gas outlet and a seed inlet at the top or upper part respectively, characterized in that the reaction tube comprises a reaction inner tube and a reaction outer tube, and the heating device is an induction heating device placed within a hollow cavity formed between the external wall of the reaction inner tube and the internal wall of the reaction outer tube, wherein the hollow cavity is filled with hydrogen, nitrogen or inert gas for protection, and is able to maintain a pressure of about 0.01 to about 5 MPa; and also to a process of producing high purity granular polysilicon using the reactor.