This work presents the control strategies for the configuration involving an open-end winding induction motor (OW-IM) fed by dual two-level inverters, which can realize the controllable power sharing between two isolated power sources without using the DC/DC converter. Based on the mathematical model of the OW-IM and the principles of the voltage vector distribution, two rotor flux calculation algorithms, namely the motor loss minimization (MLM) algorithm and the maximum power sharing capability (MPSC) algorithm are proposed and compared, with their selection strategy to select the suitable algorithm depending on the operating condition. The MLM algorithm has the optimal efficiency performance, while the MPSC algorithm can maximize the power sharing capability of the dual inverter while holding the widest operation range of the motor. Based on the dual space vector pulse-width modulation (SVPWM) control scheme, the golden section (GS) search method is introduced to allocate the stator voltage vector to the dual inverter for the power sharing demand, with a flexible iteration number to obtain a stable and efficient computational performance, which fully utilizes the power sharing capability via the voltage vector distribution. Simulation results prove the validity and the advantages of the proposed strategy. This system also lays a foundation for energy management function of the dual-power electric vehicles.

An open-end winding permanent magnet synchronous motor (PMSM) has a larger range of speed regulation than normal PMSM with the same DC voltage, and the control method is more flexible. It can also manage energy distribution between two power sources without a DC/DC converter. This paper aims at an electric vehicle equipped with OW-PMSM drive system with dual power sources and dual inverters; based on analyzing the external characteristics of each winding mode, we propose a winding mode switching strategy whose torque saturation judgmental algorithm, which is insensitive to motor’s parameters, could automatically realize upswitching of the winding mode. The proposed multi-level current hysteresis modulation algorithm could set the major power source and switch it at any time in independent mode, which accomplishes energy distribution between two power sources; its two control methods, low switching frequency method and high power difference method, could achieve different energy distribution effects. Simulation results confirm the validity and effectiveness of the winding mode switching strategy and current modulation method. They also show that an electric vehicle under the proposed control methods has better efficiency than one equipped with a traditional OW-PMSM drive system under traditional control.

Accurate tracking control of autonomous cooperative transportation systems (CTS) remains challenging owing to the complexity of the mechanisms and the high requirements of coordination between carriers. In this paper, the trajectory tracking control of a CTS with a pair of autonomous vehicles serving as carriers is investigated. A novel constraint-oriented hierarchical modeling method is proposed to describe the dynamics of the system. By dividing the system dynamics into two portions: the lower-level individual modeling and the upper-level constraints abstraction, the modeling process is significantly simplified. Then an innovative constraint-following control law is designed to address the tracking control problem under the special system topology, based on the internal and external constraints designed in the modeling process. The asymptotic convergence of the tracking error is theoretically guaranteed. To reduce potential damage of the payload during transportation, a payload force optimization method is creatively proposed. It relies on the closed-form relationship between the control input and payload forces established by the constraint-oriented modeling. The normal and shear stress on the payload is successfully limited, without affecting the trajectory tracking performance. Simulation results show that the proposed control method and the payload force optimization strategy can help achieve accurate and safe autonomous cooperative transportation simultaneously.

Eco-driving can reduce vehicle energy consumption and carbon dioxide emissions. However, the effect of eco-driving training can diminish over time. It is necessary to provide the drivers with continuous feedback. Meanwhile, bus operators also need a fair incentive system to encourage drivers to drive ecologically to reduce energy costs. Considering the influence of traffic conditions, ambient temperature, and passenger load on the energy consumption of battery electric buses, a quantitative evaluation method for eco-driving with energy consumption as a single evaluation index is proposed. Specifically, the traffic conditions recognition method based on low-frequency data is constructed and then the division of ambient temperature range is discussed. According to the traffic conditions and ambient temperature, the actual operation data of 19 battery electric buses in one year are divided into 12 control groups and the reference energy consumption of each control group is obtained. The reference energy consumption describes the range of variation in energy consumption changes for different traffic conditions and ambient temperatures. In addition, to describe the impact of passenger load on bus energy consumption, a passenger load conversion factor is proposed. Finally, the eco-driving evaluation method is constructed using the reference energy consumption and the passenger load conversion factor. Since factors of the traffic conditions, ambient temperature, and passenger load are integrated into the eco-driving evaluation method design, the score depends only on the driver’s eco-driving level and the results show that efficient drivers will not get lower scores due to driving in poor driving conditions.

A dual inverter feeding an open-end winding permanent magnet synchronous motor drive system can realize controllable power sharing or power flow between two independent power sources without a dc/dc converter. The two power sources can be selected among many options, such as fuel cells, engine generators, batteries, and supercapacitors. In this paper, the dual inverter’s voltage vector distribution and power flow principles are discussed. Based on the analyses of the overlapping area of the two inverters’ modulation ranges, the dual inverter’s modulation capability is exploited sufficiently. A novel voltage vector distribution strategy is proposed based on a dual space vector pulse-width modulation control scheme, which is composed of four patterns using basic voltage vectors, single-saturated vectors, double-saturated vectors, and linear-saturated vectors, respectively. By selecting the most suitable pattern, the power-sharing demand can be met in its maximum range while the switching frequencies of the two inverters are lowered and well-balanced. Simulation results confirm the validity and the advantages of the proposed strategy and clarify the power-sharing range in the entire operating range of the motor. This system also provides a scheme for energy management in electric vehicle applications.

A drive system with an open-end winding permanent magnet synchronous motor (OW-PMSM) fed by a dual inverter and powered by two independent power sources is suitable for electric vehicles. By using an energy conversion device as primary power source and an energy storage element as secondary power source, this configuration can not only lower the DC-bus voltage and extend the driving range, but also handle the power sharing between two power sources without a DC/DC (direct current to direct current) converter. Based on a drive system model with voltage vector distribution, this paper proposes a desired power sharing calculation method and three different voltage vector distribution methods. By their selection strategy the optimal voltage vector distribution method can be selected according to the operating conditions. On the basis of the integral synthesizing of the desired voltage vector, the proposed voltage vector distribution method can reduce the inverter switching frequency while making the primary power source follow its desired output power. Simulation results confirm the validity of the proposed methods, which improve the primary power source’s energy efficiency by regulating its output power and lessen inverter switching loss by reducing the switching frequency. This system also provides an approach to the energy management function of electric vehicles.