Multi-cell inverters with even and odd power cells comparative analysis

Аuthors

Schetinin V. E.

MobTechOnline, 4, str. 1, office 66M, proyezd 4806, Moscow, 124498, Russia

e-mail: shetininve@gmail.com

Abstract

The development of aviation technology gradually leads to increase of the on-board electrics and electronics number, including consumers of the first category, which are indispensable for the safe completion of the flight. In case of providing power from batteries, the issue of high-grade power delivery for vital consumers arises.

As a candidate solution to the problem of inverter output power increasing we suggest to use multi-cell inverter comprising of several unit inverters, allowing distribute the total load. Besides, microcontroller implementation can result in better shape of the output voltage, increase of efficiency and weight and size characteristics reduction.

The paper considers the technique of inverter output voltage generating according to an algorithm allowing approximate sinewave signal and provide equal loading of each unit inverter. Such an approximation allows increase the output voltage quality, reduce the size of each output filter, while the uniform load will allow unify the unit inverter and enhance the system flexibility in case of one of the components failure.

For an odd number of inverter cells the amplitude of the approximated signal is identical to the reference sinewave and circumscribes the sinewave over its highest point.

To provide a uniform load of all inverter cells, the author suggests divide each time interval of approximating voltage level into equal subintervals according to the number of inverter cells. With this, each voltage level is formed as a serial and parallel addition of the inverter cells voltages.

This method of the inverter cells power switches commutation allows create scalable switched mode structures of multi cell inverters. Theoretically, the maximum number of inverter cells depends on the inverter cell power switch minimum switching time.

The paper compares the simulation results obtained for inverters with even and odd number of power cells. The variant with odd number of cells dempstrated the best characteristics despite the lower number of unit cells.

Keywords:

secondary power supply, inverter, PWM, voltage spectral analysis

References

1. Brazhnikov A.V., Babin V.A., Belozerov I.R. Uspekhi sovremennogo estestvoznaniya, 2010, no. 3, pp. 110-111.

2. Mytsyk G.S. Metodologiya strukturno-algoritmicheskogo sinteza i analiza maloiskazhayushchikh ustroistv silovoi elektroniki dlya elektrotekhnicheskikh kompleksov avtonomnykh ob’’ektov (Methodology of structural and algorithmic synthesis and analysis of weakly distorting power electronics units for electrical systems of Autonomous objects), Doctors thesis, Moscow, MAI, 2001, 432 p.

3. Golovatskii V.A., Gulyakovich G.N., Konev Yu.I. Istochniki vtorichnogo elektropitaniya (Secondary power sources), Moscow, Radio i svyaz’, 1990, 280 p.

4. Konev Yu.I. Elektropitanie. Nauchno-tekhnicheskii sbornik, Moscow, 1993, no. 1, pp. 5-15.

5. Shchetinin V.E., Averin S.V. Vestnik Moskovskogo aviatsionnogo instituta, 2015, vol. 22, no. 4, pp. 159-167.

6. Shchetinin V.E., Averin S.V. Prakticheskaya silovaya elektronika, 2016, no. 62, pp. 35 — 43.