Lundell generator (alternator). Increasing comfort and safety in cars, trucks, and buses driven by combustion engines require more installed. PDF | Due to the increasing power demands in automotive applications, the conventional power generator (Lundell alternator) is rapidly reaching its limits. Abstract—Thermal analysis of Lundell alternators used in automobiles is presented. An analytical thermal model for Lun- dell alternators is proposed, and .
|Published (Last):||12 January 2016|
|PDF File Size:||2.71 Mb|
|ePub File Size:||6.73 Mb|
|Price:||Free* [*Free Regsitration Required]|
Built by scientists, for scientists. Model T Ford Club of America. In both modes of operation the switching losses will be much lower than PWM converters due to lower switching frequency.
Conversely, a nonlinear field model could be used. The efficiency of the alternator varies widely depending on load conditions, alternator speed and alternator size. Thank you very much for your kind response. The battery voltage depends on the state of charge, on its ambient temperature, and on the load level. Better cooling permits more power from a smaller machine.
Control The controller assumes no resistance or voltage drop. In an ‘alternator’, the AC current is generated in the stationary stator, and then is converted to DC by the rectifiers diodes.
The second one is the maximum output current at the highest speed, which corresponds approximately to the DC short-circuit current of the alternator I SC. Equations The Reduced Lundell Alternator block implements equations for the electrical, control, and mechanical systems that use these variables.
The armature phase resistance is measured at the rated temperature rise. Larger permanent magnet electric machines that can operate as motors or alternators can achieve today much higher efficiencies.
This is electrically and magnetically similar, but has alterjator air cooling. Click here to see To view all translated materials including this page, select Country from the country navigator on the bottom of this page. The generator should provide the same current for the load or for the battery charge from the ICE idle speed to rpm, in general onward. The main advantage of such converters is the reduced rectifier losses particularly at higher speeds if MOSFETs with low on-resistance e. Comprehensive modeling of the battery is required to exploit it optimally, as the average life of a battery is around 5 years or more for a typical car of today.
This will result in important magnetic losses in the stator core. Synchronous rectifier A synchronous rectifier is an interesting alternative to conventional diode rectifiers. The drawback of this arrangement is that if the warning lamp burns out or the “exciter” wire is disconnected, no current reaches the field windings and the alternator will not generate power.
Reduced Lundell (claw-pole) alternator with an external voltage regulator – Simulink
Slow diode rms current ISD. A voltage sensor and regulator command the DC—DC converter to keep the voltage of the battery in a certain interval roughly 12 to 17 Vdc, for 14 Vdc batteries at all times, and provides overvoltage and overcurrent protection. The average efficiency has been improved by When the same stator is rewound with m three-phase windings and N conductors per slot, the new electrical parameters can be expressed as:.
To reduce magnetic losses in the rotor, it is possible to use a laminated material but the assembly process is more complex Bretta, Until in the early s, automobiles used a DC generator called dynamo. The mmf distribution changes between the extreme shapes in Figure 3a. Influence of the number of turns on the performance The number of turns in the stator winding has a significant effect on the output performances of an alternator connected to a Conventional Diode Rectifier CDR and a battery.
The regulator-excitation circuit is often supplied by an additional half- bridge rectifier instead of the battery Exciter rectifier. Rewound alternator with BSMR. Over 21, IntechOpen readers like this topic Help us write another book on this subject and reach those readers Suggest a book topic Books open for submissions. PWM controlled full-bridge rectifier PFBR In order to exploit the alternator at its maximum capabilities, it is interesting to set an optimum power angle as proposed in Liang et al.
The alternator is coupled to the combustion motor through a belt. Simulation limitations The use of a PWM controlled rectifier fig. The owner would have to install the battery himself and charge it externally.
Increasing the filling factor will reduce copper losses, however, this is limited by the industrial production constraints Beretta, One solution is to divide each phase winding in several coil groups and to modify the winding configuration by using several switches. In fact, in all topologies, each switch has to withstand the same reverse voltage which corresponds to V OUT voltage transients neglected.
Efficiency reduces dramatically at high speeds mainly due to fan resistance. However, the flywheel magneto still powered the ignition, and since models without the starter had no battery, they continued to use magneto-powered lights.
The small amount of heat generated in the rotor can be dissipated by conduction through alternator bearings. The analysis of alternxtor equations and the experimental results Table 2 confirms that both winding systems are magnetically decoupled. Despite these drawbacks, it can be seen that the proposed model is able to provide a current versus speed curve of satisfactory accuracy.
Power Electronic Solutions to Improve the Performance of Lundell Automotive Alternators
Tune the external voltage regulator to a desired bandwidth. In the alternators with wye connected windings, two or more other auxiliary diodes are connected between the neutral point and the main rectifier output terminals. The stator current and two diode drops reduce the stator voltage.