Provided are a fluid circulation system and a method for operating same, a computer-readable medium, and a controller. The fluid circulation system comprises: a scroll expander, and an external fluid circulation path, which comprises a high-pressure fluid pipe and a low-pressure fluid pipe. The operation method comprises the following steps: before fluid is supplied to the scroll expander, making the fluid pressure in the high-pressure fluid pipe higher than the fluid pressure in the low-pressure fluid pipe by a pre-determined pressure difference; and after the pre-determined pressure difference is realized, starting the scroll expander and supplying fluid to the scroll expander. According to the present disclosure, the technical problem of a scroll expander being unable to be normally started and work can be avoided, and the invention is simple, practical, convenient, and easily implemented.