Growing process of polycrystalline cast ingot crystals

The invention relates to the technical field of solar cell cast ingots, in particular to a growing process of polycrystalline cast ingot crystals. Crystal growing time and crystal growing temperature in a crystal growing process and the elevating position of a heat insulating cage at the initial stage of crystal growing are adjusted and proportion integration differentiation control output of power is promoted, so that a gradual increasing power change trend which prevents a fused silicon component from being overcooled and can suppress the formation of microcrystals is formed, the fused silicon component is effectively prevented from being overcooled, the formation of microcrystals in crystal ingots is suppressed, product yield is increased greatly, the service life of an ingot furnace aging thermal field can be prolonged, product cost is controlled well and the market competitiveness of products is enhanced.