Based on the electricity-carbon coupling relationship

this study proposes a decision-making model for electricity and carbon market transactions considering composite regulation of carbon allowances

aiming to address issues such as insufficient market liquidity caused by free allocation. First

it designs a composite regulation mechanism integrating primary and secondary carbon markets through paid auction mechanisms

which resolves supply-demand imbalance in the dual-level carbon markets. Then

it establishes a transaction decision framework for electricity and carbon markets under this mechanism

laying the foundation for developing coordinated trading strategies between these markets. Subsequently

a dynamic carbon price prediction model and a daily allowance allocation adjustment model are developed

forming the basis for constructing transaction models in the dual-level carbon markets. Furthermore

a dual-layer electricity market transaction model incorporating carbon costs and capacity electricity prices is established. The simulation using the IEEE 39-node system demonstrates that the proposed composite regulation mechanism effectively reduces the average clearing carbon price and achieves price management. The results indicate that the transaction models under this composite regulation mechanism can maximize power generators' profits while realizing coordinated optimization between electricity and carbon markets.