Design and Test of Slender Salient Pole Hybrid Excitation Generator for While Drilling

Ye Lezhi,Song Xuanjie,Chen Zhao 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.3

The voltage-stabilized generator for Measure While Drilling is used in the oil drilling steering system. This kind of generator’s design requirements include voltage regulation range, power generation and the slender design space. Base on the axial/radial magnetic hybrid excitation synchronous generator, we propose a voltage stabilizing generator structure of hybrid excitation with slender salient pole which called SSP-HEG which is composed of hybrid excitation and permanent magnet synchronous generator. The magnetic circuit paths are analyzed by electromagnetic fi eld fi nite element method. The length of the permanent magnet-salient pole hybrid structure was designed and the regulation range of magnetic fl ux and voltage was obtained. The main parameters of the permanent magnet excitation and electric excitation generators were designed. The study results show that the salient pole structure of electric excitation can adjust the voltage in two directions which we called Bidirectional regulation generator. The voltage regulation capability of permanent magnet-salient pole hybrid structure in the forward direction is much greater than the reverse direction. The reference voltage U 0 = 344 V. When the rotating speed of the test prototype n = 4000 rpm. The maximum output power of the prototype is P = 3.1 kW. The voltage regulation capability is ± 8%.

PERFORMANCE ANALYSIS OF A NOVEL SELF-EXCITED, LIQUID-COOLED, AND BRIDGE INTEGRATED ELECTROMAGNETIC RETARDER FOR HEAVY VEHICLES WITH TRAILER

Wenguang Guo,Desheng Li,Lezhi Ye,Zhiwei Gao,Kai Zhang 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.5

To overcome the large power consumption, the braking torque heat recession, and installation difficulties for trailers of eddy current retarder (ECR), a novel self-excited, liquid-cooled, and bridge integrated retarder (SLB-EMR) is proposed in this paper. The structure and work principle of the SLB-EMR are described particularly. Based on the magnetic equivalent circuit (MEC) method, an analytical model of the eddy current braking torque considering magnetic flux leakage and end effect is established. The power generation and braking performance of the SLB-EMR are predicted by the finite element analysis (FEA). We carried out tests for the eddy current braking torque, the heat-fade of braking torque, the no-load loss torque, and natural characteristics of the SLB-EMR respectively. The test results showed that the eddy current braking torque reached 2592 N·m at 1000 r/min. The braking torque declined by 15.5 % after the braking 12 min continuously. The analytical model of eddy current braking torque, and FEA model of the generator and eddy current brake were verified by the test. Compared with the ECR, the SLB-EMR had no-power consumption and low head-fade.

Braking Torque Analysis and Control Method of a New Motor with Eddy-Current Braking and Heating System for Electric Vehicle

Zhao Xiaojuan,Zhang Yulong,Ye Lezhi 한국자동차공학회 2021 International journal of automotive technology Vol.22 No.5

To solve the problem of the serious mileage reduction of electric vehicles in winter, this paper introduces a new type of motor with eddy current braking and heating system (EBHS). EBHS can convert the vehicle’s kinetic energy into the thermal energy which can be used for heating the cabin and the battery at the right temperature. This paper proposes the structural layout and operating modes with the novel motor. The air gap magnetic density of the ECR is calculated by the magnetic circuit method. The braking torque is solved by the transient electromagnetic finite element method. The eddy current loss power at different speeds is used for analyzing heat performance. Based on MATLAB / Simulink environment, the fuzzy control method is used to simulate the EBHS’s braking energy efficiency. Compared with PTC heating, the power consumption of the new motor is reduced by 25 % and the cabin can reach 20 °C in 160 seconds. Finally, it is verified by bench test that the retarder stator stayed within 110 °C when it is continuously operated for 12 minutes. The braking torque of the finite element analysis result meet the test value, and the error rate is not higher than 11.7 %.

Design and Performance Analysis of a New Lightweight Rotor Adaptive Electromagnetic Shock Absorber for Armored Vehicles

Zhao Tong,Li Desheng,Ye Lezhi,Guo Benzhen,Li Zequn,Ma Tongxin 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.3

In order to solve the problem of the large moment of inertia of the existing rotating electromagnetic shock absorber for armored vehicles, a new lightweight rotor adaptive electromagnetic shock absorber (LR-AESA) is proposed in this paper. The LR-AESA consists of the left and right symmetrically distributed stators, a rotor in the middle and excitation coils. Secondly, based on the equivalent magnetic circuit method (EMC) and the Ampere loop theorem, and the interaction of the reaction magnetic fields between adjacent eddy current rings and the nonlinear effect of the interaction between the eddy current field and the original magnetic field are further considered, the air gap magnetic field distribution of the LR-AESA of the 10# steel rotor and the copper rotor at different speeds is derived, and the analytical expression of the damping torque is obtained. Finally, the validity of the analytical model was verified by comparison with results from the 3-D finite element method (FEM). The results show that the LR-AESA of the two material rotors can meet the requirements of technical indicators, but in the full speed section (200 ~ 2000 rpm), the copper rotor has the advantage of a wider range of the damping torque adjustment.

Research on the Data Transmission Methods in the Magneto-Thermal Coupling Model for Eddy Current Braking

Tian Jinshan,Li Desheng,Ning Keyan,Ye Lezhi 한국자동차공학회 2021 International journal of automotive technology Vol.22 No.5

The eddy current braking (ECB) is often installed on heavy-duty vehicles as the auxiliary braking component. When it works for a long time, the thermal derating of braking torque will reach about 18.5 % due to high temperature. It is important to establish an accurate magneto-thermal coupling model for the ECB high temperature steady-state braking torque prediction. In multi-field coupling calculation, there are two commonly used data transmission methods between two physics fields. One of them is transmitting average data to important geometry based on the idea of lumped parameters (lumped parameters method), and the other is mapping the data distribution to each grid cell (direct mapping method). This paper takes the ECB as the research object, analyzes the influence of the above two data transmission methods, and proposes to replace the fluid thermal coupling model with the heat conduction model in the magneto-thermal coupling model. Through calculation and analysis, using the lumped parameters method to transmit the heat generation rate, temperature and convective heat transfer coefficient all have a certain impact on the calculation accuracy of the coupling model comparing with the direct mapping method.

DESIGN AND BRAKING STABILITY ANALYSIS OF A NOVEL INTERNAL PUMP-HYDRAULIC RETARDER AXLE FOR HEAVY ARTICULATED VEHICLE

Zhiwei Gao,Desheng Li,Zongqiang Liu,Lezhi Ye 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.5

The retarder is widely used to ensure braking safety in heavy vehicles due to its noncontact braking characteristics. Currently, retarders are generally mounted on tractors, but semi-trailers have greater inertia and are prone to accidents. Therefore, the semi-trailer’s brakes have to work frequently to maintain stability during downhill braking, which causes the brakes to generate high temperatures or even failure. Based on the above problems, a novel internal pump-hydraulic retarder axle (IP-HRA) is proposed, which integrates the pump and hydraulic retarder (HR) into the support axle. The prototype of the IP-HRA was made and a bench test was conducted. In the experiment, the single-side braking power of the IP-HRA reaches 300 kW and its torque can be controlled by adjusting the outlet pressure. A co-simulation model of articulated vehicles is established to predict the braking state by computer solutions. Based on the experimental data, the methods of IP-HRA braking semi-trailer and traditional HR braking tractor are compared. The results of co-simulation show that the IP-HRA is more conducive to the braking stability of the articulated vehicle than the traditional HR when only retarder is used. Finally, the braking time and braking deceleration of IP-HRA are verified by road experiments.