Flow regulation strategy for Scroll compressor in Automotive CO2 heat pump Systems: Experimental and Simulation-Based Investigation under High-Low temperature conditions

• Integrated valve and compressor control boosts EV CO 2 system efficiency. • Validated by experiments and 1D modeling with <10% performance deviation. • Peak cooling at 34 °C; optimal heating from −5 °C to 5 °C ambient. • Control ranges: valve 30–60%, compressor 3000–4500 rpm. • Strategy enhances stability and thermal response in real conditions.