China
Africa
Explore chapters and articles related to this topic
Electric vehicle technology
Published in Tom Denton, Electric and Hybrid Vehicles, 2020
These high torque/low speed permanent magnet motors are designed to interface with standard rear differentials without the need for an intermediate gearbox. By allowing direct drive operation, it reduces powertrain complexity and cost. A direct drive system can produce over 10% efficiency gains throughout the driving cycle, representing an equivalent gain in battery usage and therefore range. Typical applications for these technologies are: city busesdelivery truckstow tractorsmining vehiclesmarine applicationsshuttles.
Design and Optimization of Permanent Magnet Synchronous Generators
Published in Levent Aydin, H Seçil Artem, Selda Oterkus, Designing Engineering Structures Using Stochastic Optimization Methods, 2020
Erhan Nergiz, Levent Aydin, Durmuş Uygun, Nilay Kucukdogan, Yucel Cetinceviz
Permanent Magnet Synchronous Generators (PMSG) are synchronous machines which are comprised of magnets instead of windings on the rotor. Permanent magnet synchronous generators do not need the mains electricity to start to produce the energy, which is why they are called self-excited generators. Due to their ability to generate energy at low speeds, they are widely used in wind turbine applications [2]. PMSGs are widely used in direct drive wind turbine systems. In direct-drive systems, the generator shaft is directly connected to the shaft of the wind turbine. Therefore, the efficiency is higher and more reliable in direct-drive systems. The advantages of direct-drive permanent magnet generators are a low cost [3, 4], high efficiency, high power density [5, 6], less maintenance, comfortable cooling, and easy control.
Wind technology design and reverse osmosis systems for off-grid and grid-connected applications
Published in Hacene Mahmoudi, Noreddine Ghaffour, Mattheus Goosen, Jochen Bundschuh, Renewable Energy Technologies for Water Desalination, 2017
Eftihia Tzen, Kyriakos Rossis, Jaime González, Pedro Cabrera, Baltasar Peñate, Vicente Subiela
Furthermore, according to the drive train condition, wind turbines can be classified into either the direct drive or geared drive group. To increase the generator rotor rotating speed and gain a higher power output, a regular geared-drive wind turbine typically uses a multi-stage gearbox to take the rotational speed from the low-speed shaft of the blade rotor and transform it into a fast rotation on the high-speed shaft of the generator rotor (Tong, 2010). The advantages of geared generator systems include lower cost and smaller size and weight. However, utilization of a gearbox can significantly lower wind turbine reliability and increase turbine noise levels and mechanical losses. By eliminating the multi-stage gearbox from a generator system, the generator shaft is directly connected to the blade rotor (Fig. 5.8). Thus, this direct-drive concept is superior in terms of energy efficiency, reliability and design simplicity.
Multi-Phase Permanent Magnet Generator with Halbach Array for Direct Driven Wind Turbine: A Hybrid Technique
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Janarthanan Balakrishnan, Chinnathambi Govindaraju
The application of the wind turbine has various benefits for the permanent magnet generators and they have gained for a considerable interest (Nasiri-Zarandi, Ajamloo, and Abbaszadeh 2020). The benefits of direct drive operation are low copper loss and variable speed owing to lack of excitation of the windings (Rao et al. 2020). Many wind generators produce electric power in the three phase voltage. But, nowadays, the multiphase genkerators are closely studied by the research works due to the fact that the significant benefits are compared with three phase generators, such as high power density, low torque ripple, and low voltage (Rajesh et al., 2021). In the five phase system, the output of DC voltage has the fundamental frequency of 1/10 of the input frequency and the peak value is 1.902 Vm (Sadeghi and Parsa 2011). In the three phase system, 1/6 of the peak voltage and input frequency is 1.732 .
An asinh-type regulator for robot manipulators with global asymptotic stability
Published in Automatika, 2020
Fernando Reyes-Cortes, Basil M. Al-Hadithi
To support our theoretical developments, this section describes the robot manipulator setup and the experimental results of the evaluated control schemes. The experimental system is a direct-drive 3-dof robot arm moving in three-dimensional space, whose workspace is a sphere with radius of 1 m, as it is shown in Figure 2. The arm links are made of 6061 aluminum actuated by brushless direct-drive servomotors from Parker Compumotor to drive the robot joints without gear reduction. Advantages of this type of direct-drive actuators include freedom from backslash, significantly lower friction phenomena compared with actuators composed by gear drives, and they work as an ideal source of applied torque when they are operated in torque mode. The servomotor models used in the experimental robot are listed in Table 1. The position information is obtained from their incremental encoders and the velocity signals from standard backwards difference algorithm applied to the position joint measurements. The electronic interface of the robot manipulator is composed by a motion control board. It is the PMDi LC228 model manufactured by Precision MicroDynamic Inc. The real-time evaluated control algorithms have been written in C language, and the sampling rate was executed at 2.5 ms on a Pentium-type host computer.
Sizing Optimization Methodology of Tidal Energy Conversion Chain Based on Double Stator Permanent Magnet Generator
Published in Electric Power Components and Systems, 2019
Jian Zhang, Luc Moreau, Judicaël Aubry, Mohamed Machmoum
There is worldwide agreement on the need to reduce greenhouse gas emissions, which drives people to explore different kinds of renewable energy. Tidal current energy has obtained a strong increasing interest due to the advantages of predictable, high power density, and huge potential characteristics in the last decade [1–3]. The method to harness tidal current energy has some similarities with wind power technology. Low maintenance, high efficiency, and reliability requirements for wind power system are also preferable for tidal current energy system. Permanent magnet sychronous generators has been widely used in wind energy turbine [4–6]. Fixed pitch system is robust and provides less power oscillation. Direct drive system eliminates the gear-box, which leads to lower maintenance cost and shorter downtime. Double Stator Cup Rotor Permanent Magnet Generator (DSCRPMG) has the merits of higher torque volume density and higher redundancy than conventional single stator permanent magnet generator [7–10]. Furthermore, it provides possibility to achieve low cogging torque by shifting the two stator a special angle. It also has higher fault tolerance level due to the two stators can be connected in parallel. Based on those reasons, fixed pitch direct drive system with DSCRPMG is researched in this paper. The researched system is illustrated in the Figure 1. One stator is shunted down in faulty situation, the healthy stator can still deliver the power to the grid.