The invention relates to a combined cooling heating and power
system driven by low-grade
waste heat. The combined cooling heating and power
system comprises an organic Rankin cycle (ORC) unit. The ORC unit is composed of a working medium pump, an
evaporator, an expander and a built-in
heat pump cycle unit which are sequentially connected and form circulation. The built-in
heat pump cycle unit comprises a first
heat exchanger, a
throttle valve, a second
heat exchanger, a compressor and a four-way
reversing valve. Heat exchange is conducted between the
evaporator and the first
heat exchanger in the built-in
heat pump cycle unit. Heat exchange is conducted between the second heat exchanger and
waste heat flow and between the second heat exchanger and externally-connected heat exchange flow. The output work end of the expander is connected with the compressor and the
electric generator. When the combined cooling heating and power
system is operated, work acted by the expander preferentially drives the compressor coaxially connected with the expander, so that output of cold energy or
heat energy of the built-in heat pump cycle unit is achieved; the remaining work drives the
electric generator to generate
electricity; therefore combined cooling heating and power of the combined cooling heating and power system is achieved. Compared with the prior art, the combined cooling heating and power system has the advantages that the process is simple; the equipment parts are small in number; the use ratio of the
waste heat energy is high; the cost of the devices of the combined cooling heating and power system is low, etc.