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In response to the era background of "comprehensive electrification" and "dual carbon plan" of electric vehicles, DC/DC converters have a good performance in terms of weight, volume, and efficiency and are widely used in fields such as solar power generation, UPS, communication, computers, and electric vehicles. At present, the DC bus voltage is an important indicator for measuring the safe and stable operation of high-voltage DC power systems in electric vehicles. Therefore, regulating the stability of bus voltage through converters has good economic benefits for the sustainable development of electric vehicles in terms of maintenance costs and effective energy management. In order to solve the problem of bus voltage resonance instability caused by negative impedance characteristics of constant power load in an electric vehicle DC power system, a sliding-mode control design strategy of three-phase interleaved bidirectional converter under constant power load was proposed. Firstly, a GPI observer was designed to estimate the state and concentrated disturbances of the system. Then, the estimated value was introduced into the controller for feedforward compensation, thereby achieving fast-tracking of the output voltage to the reference voltage. Finally, the simulation results show that the controller can effectively maintain the influence of disturbances and better improve tracking characteristics and robustness to disturbances and uncertainties. [ABSTRACT FROM AUTHOR]

In the wireless power transfer system, the front stage power supply is used to efficiently transfer power to the post-stage circuit. As a bridge connecting the front stage power supply and the rear stage circuit of the wireless power transmission system, power converter network is generally placed behind the inverter so as to achieve output filtering of inverter and stability of output voltage and current. This paper analyses the LCC (inductance-capacitance-capacitance) and LCL (inductance-capacitance-inductance) transform network circuit model, and transmission characteristics of LCC and LCL conversion networks are analysed and compared based on two different circuit topologies. By means of parameter calculation, simulation analysis, and parameter optimisation design, it is concluded that both LCC and LCL networks have different characteristics. The results show that for both LCC and LCL network topologies, when the parameters of network components satisfy certain conditions, they can relatively achieve stable voltage or current output within a certain load range to meet the specific power transmission requirements.

The capability of misalignment tolerance is vital for inductive power transfer (IPT) systems. S/SP compensation topology can provide a strong capability of misalignment tolerance if it is properly designed. This paper presents a detailed deduction process to acquire the optimal coupling coefficient, tuned at which the system can achieve minimum output voltage fluctuation. The impact of primary and secondary coupling inductance on output voltage fluctuation versus load variation was also analyzed. The output voltage fluctuation is not affected by the primary coupling inductance, but it decreases when the secondary coupling inductance is increased. Theoretical analysis was validated by both simulation and experiment. Three 200-W IPT prototypes were built. An overall efficiency of 94.1% was achieved when the coupling coefficient was 0.1733. The output voltage fluctuation was as low as 1.5% when the coupling coefficient increased by 34.5%, from 0.1288 to 0.1733. With a 900% rise in load resistance (from 80 to 800 Ω), the output voltage fluctuation decreased from 5.8% to 4.0% when the secondary coupling inductance increased from 136.3 to 250.0 μH. [ABSTRACT FROM AUTHOR]

In the wireless power transfer system, the front stage power supply is used to efficiently transfer power to the post-stage circuit. As a bridge connecting the front stage power supply and the rear stage circuit of the wireless power transmission system, power converter network is generally placed behind the inverter so as to achieve output filtering of inverter and stability of output voltage and current. This paper analyses the LCC (inductance-capacitance-capacitance) and LCL (inductance-capacitance-inductance) transform network circuit model, and transmission characteristics of LCC and LCL conversion networks are analysed and compared based on two different circuit topologies. By means of parameter calculation, simulation analysis, and parameter optimisation design, it is concluded that both LCC and LCL networks have different characteristics. The results show that for both LCC and LCL network topologies, when the parameters of network components satisfy certain conditions, they can relatively achieve stable voltage or current output within a certain load range to meet the specific power transmission requirements. [ABSTRACT FROM AUTHOR]