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The main contribution of this paper is to present a simple algorithm that theoretically and numerically assesses the switching angles of an inverter operated with the SPWM technique. This technique is the most widely used for eliminating harmonics in DC-AC converters for powering motors, renewable energy applications, household appliances, etc. Unlike conventional implementations of the SPWM technique based on the analog or digital comparison of a sinusoidal signal with a triangular signal, this paper mathematically performs this comparison. It proposes a simple solution to solve the transcendental equations arising from the mathematical analysis numerically. The technique is validated by calculating the total harmonic distortion (THD) of the generated signal theoretically and numerically, and the results indicate that the calculated angles produce the same distribution of harmonics calculated analytically and numerically. The algorithm is limited to single-phase inverters with unipolar SPWM. [ABSTRACT FROM AUTHOR]

Permanent magnet motors have become very important in recent years due to the popularization of electric vehicles in the context of the efforts to transition to zero-emission transportation. This has encouraged researchers and hobbyists to learn about electric motor design. However, designing electric motors is not a simple task, as the information to achieve it is not easily available to everyone and it is usually complicated to understand. For that reason, this paper presents the equations and a basic process to design radial flux surface-mounted PM synchronous motors. This design method is the result of combining and organizing information from previous publications to create a relatively simple design guide. The result is a table of equations and a series of general guidelines that were verified by designing and simulating a 500 W eight-pole 2.6 Nm average torque dual-rotor motor and a 20 W four-pole 106 mNm single-rotor motor. The simulations validated the equations and the design method presented in this paper to be used by those interested in the field of electric motors and vehicles; therefore, in the future, others may contribute with improvements, particularizations or optimizations of this methodology, or even create their own. [ABSTRACT FROM AUTHOR]

There is currently a growing interest in replacing the internal combustion engine with electric motors in transportation applications. However, there are different problems related to electric motors for this application. One of them is the oversizing of the energy decoupling system since to ensure that the decoupling capacitor can store the power fluctuations, the capacitance required by the system is usually oversized. This leads to preference for the use of capacitors with construction technologies that have a lower lifetime than the remaining elements of the propulsion system, directly affecting the reliability of the system. In this article, the energy flow handled by the decoupling capacitor is analyzed considering the critical case of operation of an induction motor to minimize the capacitance required by the propulsion system; emphasizing the conditions that generate a higher energy return, from the motor mode of the electric machine to the decoupling capacitor. From the energy analysis, an equation for the capacitor calculation is obtained, involving proportionality factors that relate to the different operating powers, reducing up to 62.2% of the capacitance value required by the decoupling system, under conditions of maximum energy return in motor mode, compared to existing equations in the literature. [ABSTRACT FROM AUTHOR]