Abstract: Copper alloys serve as fundamental materials in modern industry. Large-section copper ingots are susceptible to thermodynamic and dynamic disturbances during continuous casting, resulting in internal shrinkage cavities and micro-porosity at the final solidification zone. Systematic research on the formation mechanism and prevention of such defects is of great practical engineering significance. Based on production data from a continuous casting project of high-strength and high-conductivity copper, this paper thoroughly analyzes how the melt temperature field, flow field and solute distribution affect solid-liquid phase transformation. Focusing on critical technological parameters including mold heat exchange efficiency, spatiotemporal distribution of cooling water flux in the secondary cooling zone and feeding channel morphology at solidification terminal, the quantitative relationship between these parameters and central densification of ingots is clarified. Targeted control technologies including nonlinear regulation of electromagnetic stirring, determination of operating window for dynamic soft reduction and adaptive optimization of air-water atomization are adopted to reconstruct the boundary conditions for copper ingot solidification. Physical simulations and industrial trials verify that the optimized process inhibits dendrite bridging, facilitates the formation of equiaxed grain network, drastically reduces the generation of macroscopic shrinkage and micro-porosity, and improves the internal quality stability of cast ingots.