We discuss the conditions under which some polychromatic light photovoltaic spatial solitons can be formed in a photorefractive crystal with a positive perturbation refractive index- Generally, under these conditions we can form bright-bright,dark-dark and bright-dark polychromatic light photovoltaic spatial solitons in the crystal- In the case of bright-bright solitons, if we launch a monochromatic beam(ray2,its effective Glass constant is less than that of the background), bright soliton cannot be obtained- But if we add another monochromatic beam(ray1, its effective Glass constant is larger than that of the background beam), both ray1 and ray2 can form bright solitons under some condition- This gives a new way to control ray2 with ray1- It is shown that the width of bright-bright solitons can be modified by the peak intensity of ray1-