High power density by combining of a double stator and an opposite-magnets linear generator in a dual-type free-piston engine generator

2020 ◽  
pp. 1-16
Author(s):  
Mitsuhide Sato ◽  
Masami Nirei ◽  
Yuichiro Yamanaka ◽  
Yinggang Bu ◽  
Tsutomu Mizuno
Keyword(s):  
Power Density ◽  
High Power ◽  
Permanent Magnets ◽  
High Efficiency ◽  
Installation Space ◽  
Piston Engine ◽  
Element Analysis ◽  
Free Piston ◽  
Linear Generator ◽  
Free Piston Engine

A linear generator system based on a free-piston engine is expected to be a highly efficient power-generation engine for series hybrid vehicles. However, the engine generator must produce in a limited installation space the very high power required to drive a car. Consequently, considering the car-mounting situation, higher power density is required by means of reduced generator size and higher efficiency. In this paper, a cylindrical double-stator linear synchronous generator with opposing permanent magnets is used for free-piston engine. The double stator realizes smaller size, and using opposing magnets achieves a larger thrust constant than that with a single stator. In a finite-element analysis, the high-efficiency area is expanded compared to a surface-magnet type of the same size. Furthermore, this paper clarifies the effectiveness for improved power density with maximum-generation control in a simulation of a dual-sided engine model.

scholarly journals Design considerations of a linear generator for a range extender application

2015 ◽  
Vol 64 (4) ◽  
pp. 581-592
Author(s):  
Un-Jae Seo ◽  
Björn Riemer ◽  
Rüdiger Appunn ◽  
Kay Hameyer
Keyword(s):  
Electric Vehicle ◽  
High Efficiency ◽  
Piston Engine ◽  
Free Piston ◽  
Full Load ◽  
Linear Generator ◽  
Design Considerations ◽  
Range Extender ◽  
Free Piston Engine ◽  
Linear Generators

Abstract The free piston linear generator is a new range extender concept for the application in a full electric vehicle. The free piston engine driven linear generators can achieve high efficiency at part and full load which is suitable for the range extender application. This paper presents requirements for designing a linear generator deduced from a basic analysis of a free piston linear generator.

scholarly journals Operation Range of Generation Braking Force to Achieve High Efficiency Considering Combustion in a Free-Piston Engine Linear Generator System

2018 ◽  
Vol 7 (4) ◽  
pp. 343-350 ◽  
Author(s):  
Mitsuhide Sato ◽  
Masami Nirei ◽  
Yuichiro Yamanaka ◽  
Hironobu Murata ◽  
Yinggang Bu ◽  
...  
Keyword(s):  
High Efficiency ◽  
Piston Engine ◽  
Generator System ◽  
Free Piston ◽  
Linear Generator ◽  
Free Piston Engine ◽  
Braking Force

scholarly journals Research on the Operating Characteristics of Hydraulic Free-Piston Engines: A Systematic Review and Meta-Analysis

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3530
Author(s):  
Fukang Ma ◽  
Shuanlu Zhang ◽  
Zhenfeng Zhao ◽  
Yifang Wang
Keyword(s):  
Systematic Review ◽  
High Efficiency ◽  
Meta Analysis ◽  
Combustion Process ◽  
Research Progress ◽  
Future Research ◽  
Operating Characteristics ◽  
Piston Engine ◽  
Free Piston ◽  
Free Piston Engine

The hydraulic free-piston engine (HFPE) is a kind of hybrid-powered machine which combines the reciprocating piston-type internal combustion engine and the plunger pump as a whole. In recent years, the HFPE has been investigated by a number of research groups worldwide due to its potential advantages of high efficiency, energy savings, reduced emissions and multi-fuel operation. Therefore, our study aimed to assess the operating characteristics, core questions and research progress of HFPEs via a systematic review and meta-analysis. We included operational control, starting characteristics, misfire characteristics, in-cylinder working processes and operating stability. We conducted the literature search using electronic databases. The research on HFPEs has mainly concentrated on four kinds of free-piston engine, according to piston arrangement form: single piston, dual pistons, opposed pistons and four-cylinder complex configuration. HFPE research in China is mainly conducted in Zhejiang University, Tianjin University, Jilin University and the Beijing Institute of Technology. In addition, in China, research has mainly focused on the in-cylinder combustion process while a piston is free by considering in-cylinder combustion machinery and piston dynamics. Regarding future research, it is very important that we solve the instabilities brought about by chance fluctuations in the combustion process, which will involve the hydraulic system’s efficiency, the cyclical variation, the method of predicting instability and the recovery after instability.

Modeling and Design of a Tubular Linear Generator for Direct-Drive Free-Piston Engine

2021 ◽  
Author(s):  
Christophe S. Cyusa ◽  
Tamanwe Payarou ◽  
Dwaipayan Barman ◽  
Tamas Bertenyi ◽  
Philip Raphals ◽  
...  
Keyword(s):  
Direct Drive ◽  
Piston Engine ◽  
Free Piston ◽  
Linear Generator ◽  
Free Piston Engine

Development of free piston engine linear generator system and a resonant pendulum type control method

2020 ◽  
pp. 146808742093124
Author(s):  
Hidemasa Kosaka ◽  
Tomoyuki Akita ◽  
Shigeaki Goto ◽  
Yoshihiro Hotta
Keyword(s):  
Control Method ◽  
Experimental Result ◽  
Piston Engine ◽  
Piston Motion ◽  
Generator System ◽  
Free Piston ◽  
Linear Generator ◽  
Reference Profile ◽  
Cycle Simulation ◽  
Free Piston Engine

A free piston engine linear generator, which has the potential of the compact physique, high brake efficiency and high flexibility for fuel, has been developed. The developed free piston engine linear generator consists of a two-stroke combustion unit, an air-bounce chamber and a linear generator. The key technologies to realize the continuous operation are the control method and lubricating and cooling strategies. The proposed structure is featured as a piston shape with two different diameters coaxially, called a “W-shape” piston, which has an empty space inside for the oil cooling path. The performance of the structure is evaluated by a one-dimensional cycle simulation. The result indicates the possible output power of 10 kW and thermal efficiency of 42% using premixed charge compression ignition combustion strategy. The control method is another challenge of the free piston engine linear generator. This work proposes two strategies of the position feedback control method and the resonant pendulum type control method. The first method has the function of the feedback loops for the piston position and velocity so that the piston motion follows the reference profile calculated in advance. The experimental results show the limited range of operation because the fixed profile does not absorb the deviation of the piston motion due to the combustion deviation. The second method is based on the speed control without a fixed reference profile of the piston motion. The experimental result shows the robustness to the change in operating parameters such as ignition position, amount of fuel and desired power output.

scholarly journals Tribological Characteristics of Piston Ring in a Free-piston Engine for Linear Generator

2014 ◽  
Vol 61 ◽  
pp. 979-983 ◽  
Author(s):  
Chenheng Yuan ◽  
Huihua Feng ◽  
Zhengxing Zuo ◽  
Yanxiao Li
Keyword(s):  
Piston Ring ◽  
Tribological Characteristics ◽  
Piston Engine ◽  
Free Piston ◽  
Linear Generator ◽  
Free Piston Engine

Transient Control of a Hydraulic Free Piston Engine

2013 ◽  
Author(s):  
Ke Li ◽  
Chen Zhang ◽  
Zongxuan Sun
Keyword(s):  
High Efficiency ◽  
Combustion Engine ◽  
Tracking Error ◽  
Control Signal ◽  
Piston Engine ◽  
Piston Motion ◽  
Free Piston ◽  
Engine Operation ◽  
Free Piston Engine ◽  
Transient Period

The free piston engine (FPE) is a type of internal combustion engine (ICE) with no crankshaft, so that its piston motion is no longer constrained by mechanical linkages. The FPE has a high potential in terms of energy saving given its simple structure, high modularity and high efficiency. One of the technical barriers that prevents the wide spread of the FPE technology, is the lack of precise piston motion control. Previously, a robust repetitive controller is designed and implemented to form a virtual crankshaft that would provide a precise and stable engine operation. The experimental data of engine motoring tests with virtual crankshaft demonstrates the effectiveness of the controller. However, the presence of a transient period after a single combustion event prevents the engine from continuous firing. This paper presents a modified control scheme, which utilizes a reference and control signal shifting technique to modify the tracking error and the control signal to reduce the transient period.

Sign in / Sign up

Export Citation Format

Share Document