According to Jyotish Tatva Parkash

The seven and a half year period during which Saturn transits in the twelfth,
The first and second houses from the birth Rashi (moon sign) are called the Sadhesati of Saturn.

Your birth rash is Taurus therefore the period during which Saturn transits in Aries, Taurus
and Gemini is called Sadeshesati of saturan

Shani Sade Sati occurs in three parts. Each part is of approximately 2 years 6 months. [5] If one pays attention to the facts, then the purpose of Shani is to teach the person for life. Therefore, during the first 2 years 6 months, Saturn disturbs the person mentally. In the second part, it causes damage financially, physically, faith etc., and in the third and last part, Shani Maharaj, compensates for the damage caused by himself. This is the time when a person comes to know the truth.

One sadhesati is made up of three periods of a approximately two and half years each, because
Saturn travels in one rashi for two and half years.
Normally in the lifetime of a person, the Sadhesati of saturn occurs three times