## 1 Introduction
This model is based on fundamental principles and enables power consumption and mass flow rate predictions for both single-speed and variable-speed compressors. The level of accuracy of the model is notable, with errors between the predicted and experimental values that are within 10% [24]. A semi-empirical model for variable-speed scroll compressors has been developed by [PERSON] et al. This model is based on physical laws and predicts values for volumetric efficiency, adiabatic efficiency, and the product of electrical and mechanical efficiencies. When compared to the experimental data, the deviations for these predicted values fall within the ranges of \(+\)2.3/\(-\)1%, \(+\)9.1/\(-\)5.3%, and \(\pm\)4.95%, respectively. Similarly, the predicted values for the refrigerant mass flow rate and discharge temperature also have deviations within the ranges of \(+\)1/\(-\)1.1 g/s and \(+\)0.6/\(-\)0.8 K, respectively, compared to the experimental data. As for power consumption, the deviation is \(+\)55/\(-\)90 W when compared to the experimental data [25]. [PERSON] et al. have developed a semi-empirical thermodynamic model for the volumetric efficiency and power consumption of reciprocating compressors. The predicted values for the compressor power consumption have an error of less than 1% compared to the experimental data [26]. However, the aforementioned models do not consider the impact of the suction state of the compressor (superheated suction and wet compression) on the compressor model. Additionally, wet compression can make the vapor compression refrigeration cycle with pure working fluid closer to the ideal Carnot cycle. When the suction dryness is low, the liquid droplets drawn into the compressor completely vaporize within a short time, thereby improving compressor performance and reducing discharge temperature [27]. The wet compression cycle offers the highest possible efficiency for thermodynamic cycles operating between two temperatures with a heat sink and heat source [28; 29]. Therefore, the development of a wet compression model for compressors holds significant importance in the facilitation of system simulation and optimization. In brief, there is a dearth of research on modeling variable-speed compressors that undergo fluctuations in suction states. The compressor frequency and refrigerant state at the suction port exhibit a complex pattern during operation, leading to significant variations in compressor performance across diverse operating conditions. Therefore, it is crucial to delve into its properties and to create compressor models to address this issue. Rolling piston compressors are low-capacity compressors that are characterized by their small size, light weight, low cost, and high performance. They are widely used in low-capacity refrigeration and heat pump systems [22], and establishing a mathematical model for them is particularly significant. Therefore, this paper presents an in-depth analysis of the effects of multiple factors on the electrical efficiency of a variable-speed rolling piston compressor. The factors studied include compressor frequency, suction superheat, suction dryness, evaporation temperature, and compression ratio. Through rigorous experimentation, we determined the variation law of the electrical efficiency. Furthermore, we developed a reliable model for steady-state electrical efficiency that can be applied to both the wet compression and the superheated suction stages of the rolling piston compressor. This model was validated through experiments, ensuring its accuracy and usefulness in practical applications.