METHOD FOR SHAPING NETWORK CURRENT OF FOUR-QUADRANT CONVERTER Russian patent published in 2011 - IPC H02M7/72 

FIELD: electricity.

SUBSTANCE: method for shaping network current of four-quadrant converter consists in the fact that amplitude of the specified current value is introduced and the specified instantaneous value of current is determined by formula i₃=i₃sinφt; source of input voltage is closed to line inductance in positive half-period of supply voltage until current reaches the sum of the specified magnitude and value of allowable deviation; source of input voltage is opened until current reaches the difference of magnitude and value of allowable deviation. Then, source of input voltage is closed again to line inductance until current reaches the sum of the specified magnitude and value of allowable deviation; source of input voltage is opened until current reaches the difference of the specified magnitude and value of allowable deviation, etc. till the end of positive half-period of supply voltage; source of input voltage is closed in negative half-period of supply voltage to line inductance until current reaches the difference of the specified magnitude and value of allowable deviation; source of input voltage is opened until current reaches the sum of the specified magnitude and value of allowable deviation; then, source of input voltage is closed again to line inductance until current reaches the difference of the specified magnitude and value of allowable deviation; source of input voltage is opened until current reaches the sum of the specified magnitude and value of allowable deviation, etc. till the end of negative half-period; thus, width of the main current corridor relative to the specified value of network current is formed. In the above method the width of current corridor at the beginning and at the end of each half-period is set as fixed and comprising of 0.2 to 0.5 of width of the main current corridor, and value of load current of converter is measured. When load current value of four-quadrant converter is higher than value of network current in modulus, network current is controlled in additional current corridor.

EFFECT: possibility of shaping the curve of network current with improved shape close to sine shape, which allows increasing power coefficient of converter in comparison to the method of shaping of network current with current corridor having similar width.

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