Starter Generator Research Articles

Design and Performance Analysis of Windings Considering High Frequency Loss and Connection Mode of a Starter Generator

The starter generator is the key component of the aircraft’s starter generation system. A high power density, efficiency, and reliability are essential for an aircraft’s starter generator. The configuration of the windings is closely related to the performance of the starter generator. In this paper, the winding performance analysis and design are studied. Considering the skin effect, circulation effect, and proximity effect, a calculation model of winding loss under high-frequency operation is established. The motor performance under different winding connections is compared. Through a comprehensive comparison of starting performance, generation loss, and process performance differences, the optimum configuration of windings is identified. The performance of the starter generator including winding resistance, current, and no-load loss was tested on the prototype platform to verify the rationality and correctness of the analysis and design methods.

Loss and Thermal Analysis of a High-Power-Density Permanent Magnet Starter/Generator

Reducing heat and improving the overall operation stability of the motor play a key role in the design of a starting engine. This paper focuses on the loss and thermal analysis of a permanent magnet (PM) brushless machine used in starter generators. The loss of the starter generator was calculated through a combination of theoretical analysis and the finite element method. A thermal analysis model was established based on the division of the fluid domain, boundary grid, heat source setting, and so on. The temperature fields of the whole motor and the main components were calculated and analyzed. The main factors affecting the air cooling effect were analyzed, including air flow rate, air temperature, and motor speed. A prototype experimental platform of the SG motor was built. The efficiency and temperature rise in the motor were tested. The temperature values were compared with the calculated values. The experimental results show that the performance of the motor is excellent, and the error between the temperature and the design calculation is less than 10% under each load torque. The accuracy of the thermal analysis method is verified. The correctness of the motor transient model was also confirmed through a temperature rise experiment under rated conditions, providing a research basis for improving operation efficiency.

Increasing R&D effectiveness: planning as a tool for reducing technological risk in engine development

This article presents the basics and results of applying the Lean R&D methodology in planning as a crucial tool for enhancing the success of innovative projects. By following a step-by-step process, the effectiveness of project execution is improved through a comprehensive list of key tests that increase in complexity. This approach simplifies early identification of potential issues and reduces the risk of errors during the design phase. A new lean planning method is introduced, including assessing the readiness of the designed product at the design stage based on a roadmap. It also involves analyzing the critical elements (CE) of the product and determining their current level of readiness. Additionally, a functional analysis of the CE is conducted, followed by separate planning for the development of each element. Finally, the project is checked against a set of criteria to achieve technology readiness levels (TRL+). The process of lean planning is demonstrated in the field of engine building through the case of integrated starter-generator (SG) development. Specific elements of the planning structure are considered, and a functional analysis of the SG’s CE is conducted for both internal and external primary and secondary impacts. Their interactions and control events are determined according to detailed TRL+ criteria, allowing for the reduction of technological risks, shorter project execution times, and increased efficiency in innovative technology development through the use of this planning tool

Multidisciplinary Design and Optimization of High-Speed Hybrid Excitation Starter Generator for Aircraft Power System

Multidisciplinary Design and Optimization of High-Speed Hybrid Excitation Starter Generator for Aircraft Power System

Multiobjective Optimization of High Power Density Outer Rotor PM Starter Generator Considering Electromagnetic and Temperature Characteristics

Multiobjective Optimization of High Power Density Outer Rotor PM Starter Generator Considering Electromagnetic and Temperature Characteristics

Integration of a Belt Starter Generator in a Flex-Fuel Vehicle

<div>The concern with global warming has led to the creation of legislation aimed at minimizing this phenomenon. As a result, the development of technologies to minimize vehicle emissions and reduce fuel consumption has gained market share. A promising alternative is the use of a belt starter generator (BSG): an electric machine to replace the vehicle’s alternator. This research analyzes the effects of introducing a 12 V BSG into a flex-fuel vehicle, specifically examining its impact on fuel economy and CO<sub>2</sub> emissions when using both gasoline and ethanol. The utilization of a low-voltage BSG in a flex-fuel vehicle has not been previously studied. Numerical simulations and experimental fuel consumption and CO<sub>2</sub> emissions tests were performed for the normal production flex-fuel baseline configuration and the vehicle with the 12 V BSG, following the standards ABNT NBR 6601 and ABNT NBR 7024. The use of the BSG led to a 10.06% reduction in CO<sub>2</sub> emission in the urban cycle for the vehicle running on gasoline and a 6.28% reduction in energy consumption in the combined cycle. The results demonstrated that the low-voltage BSG is a promising solution for reducing fuel consumption and GHG emissions in flex-fuel vehicles. The electrical machine installation required minimal modifications to the vehicle and had a low adaptation cost. The BSG can also improve vehicle performance and drivability.</div>

Loss Minimization Control of Aircraft Wound-Rotor Synchronous Starter–Generator in the Starting Mode

Loss Minimization Control of Aircraft Wound-Rotor Synchronous Starter–Generator in the Starting Mode

Multi-Electric Aero Engine Control and Hardware-in-the-Loop Verification with Starter Generator Coordination

The starter generator, characterized by controllable starting torque and disturbance in generator load torque, poses challenges for the multi-electric aero engine control. The key to addressing this issue lies in multi-electric aero engine control with the collaboration of a starter generator. Firstly, a multi-electric aero engine model is established, comprising a full-state turbofan engine model to enhance low-speed simulation capability and an external characteristic model of a starter generator to improve real-time simulation capability. Subsequently, the control methods for a multi-electric aero engine with starter generator coordination are proposed in three processes, including the starting process, acceleration/deceleration process, and steady-state process. During the starting process, the acceleration is controlled by coordinating the torque of the starter generator and the fuel of the aero engine. During the acceleration/deceleration process, the fuel limit value is adjusted based on the electrical load of the starter generator. During the steady-state process, the fuel is compensated based on the q-axis current of the starting generator in response to load torque disturbance. Finally, hardware-in-the-loop simulation experiments are conducted for the control of a multi-electric aero engine. The results show that the coordination reduces the oscillation of the acceleration during the startup of a multi-electric aero engine, enhancing its ability to resist disturbances from electrical load fluctuations during power generation.

Multi-modal safety analysis of the more electric aircraft starter generator system

Multi-modal safety analysis of the more electric aircraft starter generator system

Demonstration of 2027 Emissions Standards Compliance Using Heavy-Duty Gasoline Compression Ignition with P1 Hybridization

<div>Heavy-duty on-road engines are expected to conform to an ultralow NO<sub>x</sub> (ULNO<sub>x</sub>) standard of 0.027 g/kWh over the composite US heavy-duty transient federal test procedure (HD-FTP) cycle by 2031, a 90% reduction compared to 2010 emissions standards. Additionally, these engines are expected to conform to Phase 2 greenhouse gas regulations, which require tailpipe CO<sub>2</sub> emissions under 579 g/kWh. This study experimentally demonstrates the ability of high fuel stratification gasoline compression ignition (HFS-GCI) to satisfy these emissions standards. Steady-state and transient tests are conducted on a prototype multi-cylinder heavy-duty GCI engine based on a 2010-compliant Cummins ISX15 diesel engine with a urea-SCR aftertreatment system (ATS). Steady-state calibration exercises are undertaken to develop highly fuel-efficient GCI calibration maps at both cold-start and warmed up conditions. A P1 hybrid architecture is proposed to enable the use of an integrated starter generator (ISG) capable of spinning the engine up to idle speeds and an electrically heated ATS for fast heat-up and better thermal management. The combined solution is shown to satisfy the aforementioned ULNO<sub>x</sub> standard across the composite HD-FTP while decreasing the CO<sub>2</sub> emissions compared to the 2013 baseline values, cementing the credentials of low-cetane fuels as viable, near-term alternatives to diesel fuel in heavy-duty on-road engines.</div>

Fault Diagnosis of Rotating Rectifier in Aircraft Wound-Rotor Synchronous Starter–Generator Based on Stator Currents Under all Operational Processes

Fault Diagnosis of Rotating Rectifier in Aircraft Wound-Rotor Synchronous Starter–Generator Based on Stator Currents Under all Operational Processes

On the Possibility of Introducing an Integrated Starter–Generator into a Gas-Turbine Engine Body

On the Possibility of Introducing an Integrated Starter–Generator into a Gas-Turbine Engine Body

Permanent-Magnet Machines as Aircraft Integrated Starter–Generators

Permanent-Magnet Machines as Aircraft Integrated Starter–Generators

A Cooling Jacket Design for a Starter–Generator Body

A Cooling Jacket Design for a Starter–Generator Body

A Starter–Generator Based on a Synchronous Machine with Permanent Magnets

A Starter–Generator Based on a Synchronous Machine with Permanent Magnets

Armature Reaction Analysis and Performance Optimization of Hybrid Excitation Starter Generator for Electric Vehicle Range Extender

The armature reaction of the hybrid excitation starter generator (HESG) under load conditions will affect the distribution of the main magnetic field and the output performance. However, using the conventional field-circuit combination method to study the armature reaction has the problem of low accuracy and inaccurate influencing factors. Therefore, this paper proposed a graphical method to analyze the armature reaction and a new type of HESG with a combined-pole permanent magnet (PM) rotor and claw-pole electromagnetic rotor. The analytical formula of the voltage regulation rate under the armature reaction was derived using the graphical method. The main influencing parameters of the armature reaction magnetic field (ARMF) were analyzed, and the overall output performance was analyzed using finite element software. On this basis, comparison analyses before and after optimization and the prototype test were carried out. The results show that the direct-axis armature reaction reactance, quadrature-axis armature reaction reactance, and voltage regulation rate of the optimized HESG were significantly reduced, the output voltage range of the whole machine was wide, and the voltage regulation performance was good.

Design and Analysis of a Stator Field Control Permanent Magnet Synchronous Starter–Generator System

In recent years, the permanent magnet synchronous motor (PMSM) has garnered significant attention due to its high power density and efficiency in applications such as electric vehicles, aviation, and other domains. This paper proposes a stator field control permanent magnet synchronous starter–generator (SFC-PMSSG) system. The starter–generator system comprises the SFC-PMSSG and a field controller (FC). A mathematical model of the SFC-PMSSG is established. Finite element analysis (FEA) is employed to obtain the electromagnetic parameters of the SFC-PMSSG, and the characteristics of the SFC-PMSSG are analyzed. A circuit simulation model of the FC is established to assess the control effect and the loss of the FC. A co-analysis of the system is conducted, and the results demonstrate that the SFC-PMSSG system can maintain output voltage stability as load and speed conditions vary.

Improved startup control of aero doubly salient electromagnetic starter generator based on optimised currents distribution with advanced angle commutation

AbstractDoubly salient electromagnetic machine (DSEM) can constitute a competitive rugged starter generator (SG) system. But under the traditional startup control method, the field current is set to the rated value regardless of speed or load torque conditions, and the phase currents are controlled with standard angle commutation, bringing in large power loss as well as non‐negligible torque ripple. To overcome these shortcomings, based on the established DSEM power loss calculation model, a currents distribution strategy is proposed according to the obtained quantitative relationship between DSEM power loss and field current under multiple speed and load torque conditions. Then, to identify the load torque for practical implementation, a novel torque observer is designed based on back propagation (BP) neural network algorithm. Afterwards, to further improve the startup torque performance, currents distribution with advanced angle commutation (AAC) strategy is put forward, where the optimal advanced angle is selected from a 3‐D lookup table to achieve the minimal commutation torque ripple. Under the proposed control strategies, DSEM power loss as well as the output torque ripple are desired to be decreased, the simulation and experimental results on a 12/8‐pole DSEM prototype verify the correctness and feasibility of the proposed strategies under multiple operating conditions.

Regenerated Energy Absorption Methods for More Electric Aircraft Starter/Generator System

In more electric aircrafts, more motor loads are applied onboard. When the motor is braking, the regenerated energy need to be absorb to avoid dc-link voltage variations. Two regenerated energy absorption methods are proposed for the generator based on diode rectifiers and the starter/generator (SG) based on active rectifiers respectively. When the regenerated power is lower than other loaded power, both SG and generator systems can absorb it by reducing the output power. When the regenerated power is higher than other loaded power, if the SG is directly connected to the engine shaft, the regenerated energy can be absorbed by changing the SG operation from generating to motoring. The regenerated energy can be returned directly to the dc-link without extra devices and the dc-link voltage is under control during the regenerated energy absorption. The efficiency is improved and the heat is reduced by the proposed regenerated energy absorption methods. The generator and SG systems are implemented and the regenerated energy absorption methods are verified by experiments. The efficiency of the onboard electrical power system is improved.

Thermal Analysis of a Flux-Switching Permanent Magnet Machine for Hybrid Electric Vehicles

This paper investigates the loss and thermal characteristics of a three-phase 10 kW flux-switching permanent magnet (FSPM) machine, which is used as an integrated starter generator (ISG) for hybrid electric vehicles (HEVs). In this paper, an improved method considering both DC-bias component and minor hysteresis loops in iron flux-density distribution is proposed to calculate core loss more precisely. Then, a lumped parameter thermal network (LPTN) model is constructed to predict transient thermal behavior of the FSPM machine, which takes into consideration various losses as heat sources determined from predictions and experiments. Meanwhile, a simplified one-dimensional (1D) steady heat conduction (1D-SHC) model with two heat sources in cylindrical coordinates is also proposed to predict the thermal behavior. To verify the two methods above, transient and steady thermal analyses of the FSPM machine were performed by computational fluid dynamics (CFD) based on the losses mentioned above. Finally, the predicted results from both LPTN and 1D-SHC were verified by the experiments on a prototyped FSPM machine.