The invention provides an open-type bidirectional
thermodynamic cycle and a second-class thermally-driven compression
heat pump belonging to the technical fields of
heat energy utilization and heat pumps. The open-type bidirectional
thermodynamic cycle is formed by a process 12 of heated
medium pressure reduction beginning from a high temperature, a process 23 of releasing heat towards a low-temperature heat source, a process 34 of
pressure rise beginning from a low temperature, a process 45 of absorbing heat from a medium-temperature heat source and a process 56 of
pressure rise beginning from a medium temperature. The outside communicates with an expansion
machine by virtue of a heated medium channel; the expansion
machine communicates with a compressor through a cooler by virtue of a heated medium channel; the compressor communicates with a second compressor through a
heat exchanger by virtue of a heated medium channel; the second compressor communicates with the outside by virtue of a heated medium channel; the cooler communicates with the outside by virtue of a
cooling medium channel; the
heat exchanger communicates with the outside by virtue of a medium-temperature heat medium channelA heated medium channel which communicates with an expansion
machine is arranged at the outside; the expansion machine is provided with a heated medium channel which communicates with a compressor through a cooler; the compressor is provided with a heated medium channel which communicates with a second compressor through a
heat exchanger; the second compressor is provided with a heated medium channel which communicates with the outside; the cooler is provided with a
cooling medium channel which communicates with the outside; the
heat supply device is provided with a heated medium channel which communicates with the outside; the heat exchanger is internally provided with a medium-temperature heat medium channel which communicates with the outside; and the expansion machine is connected with the compressor and the second compressor and is used for transmitting power, so that the second-class thermally-driven compression
heat pump is formed.