Procedure for regulating the D.C. voltage of a rectifier

Claim 2

Procedure according to claim 1, characterized in that said sine and cosine curves are synchronized by comparing the phase angle between said localized vector ( E ) of the mains voltages and the calculation coordinates at the zero point of the imaginary component (Eb) of said localized vector ( E ) of the mains voltage or continuously by adjusting the imaginary component of the localized voltage vector to zero in the coordinate system used.

Claim 3

Procedure according to claim 2, characterized in that the imaginary component (Eb) of the localized vector is calculated from the phase voltages (Er,Es,Et) in a stationary coordinate system, that said imaginary component is used to produce a rectangular wave synchronized with its zero point and used for the control of the phase-locked loop (PLL1), and that said phase-locked loop (PLL1) produces the addresses of one or more memory circuits, in which said sine and cosine curves are stored.

Claim 4

Procedure according to claim 2, characterized in that the imaginary component (Eq) of said localized vector ( E ) of the mains voltage is adjusted to zero by calculating the actual value (Eqa) of said component (Eq), multiplying the real and imaginary components (Ea,Eb) of a stationary coordinate system corresponding to the mains voltage (Er,Es,Et) by the cosine and sine values of the coordinate angle obtained from a phase-locked loop (PLL2) in accordance with conversion equations known in themselves, comparing said actual value (Eqa) to a zero reference (Eqr), passing the difference quantity thus obtained into a controller (20) whose output controls a voltage-controlled oscillator 4, and counting the pulses of said oscillator by means of a counter (5) whose output is used as the address of a memory unit (6) holding the pure sine and cosine curves, and that the sine and cosine values corresponding to the address of said memory unit are used for the calculation of the actual value (Eqa) of said imaginary component.

Claim 5

Procedure according to claim 1, characterized in that the real part (Ed) of the localized voltage vector corresponding to the absolute value of the phase voltage indicators, said real part (Ed) being the same as the real component (Udr) of the localized vector ( U ) of the rectifier voltages, is calculated in a coordinate system tied to said vector from the real and imaginary components (Ea,Eb) of the localized voltage vector in a manner known in itself, that the d.c. voltage (Udca) of the rectifier is compared to a reference (Udcr) and the difference quantity thus obtained is passed into a controller (10) which provides the imaginary component (Uqr) of the localized vector ( U ) of the rectifier voltages, that said components (Udr,Uqr) determine the direction and magnitude of the localized vector describing the rectifier voltages, and that the localized vector ( U ) corresponding to the desired rectifier voltages (Ur,Us,Ut) is converted to a stationary coordinate system and the real and imaginary components (Ua,Ub) of the localized vector thus obtained are further converted into three-phase modulation reference signals (Umr,Ums,Umt).

Claim 6

Procedure according to any one of the preceding claims, characterized in that the formation of the real component (Udr) of said localized vector of the rectifier voltages (Ur,Us,Ut) is implemented using feedforward (27) depending on the difference quantity between the measured value of the d.c. voltage (Udca) of the rectifier bridge and its reference (Udcr).

Claim 7

Procedure according to any one of the preceding claims, characterized in that the effect of the internal resistances (R) of the filtering coils (L) connected to the mains voltages (Er,Es,Et) is eliminated using an additional reference proportional to the imaginary component (Uqr).

Claim 8

Procedure according to any one of the preceding claims, characterized in that the allowed maximum value of the real component (Udr) of said localized vector of the rectifier voltages (Ur,Us,Ut) is decreased as the absolute value of the imaginary component (Uqr) increases.

Claim 9

Procedure according to claim 4, characterized in that the multiplication of the real and imaginary components (Ea,Eb) of said stationary coordinate system by the cosine and sine values of the angle obtained from a phase-locked loop (PLL2) is performed by means of one or more D/A converters (12',13').

Claim 10

Procedure according to claim 5, characterized in that the calculation of the real part (Ed) of said localized voltage vector, which real part (Ed) is the same as the real component (Udr) of the localized vector ( U ) of the rectifier voltages, is performed using one or more multiplying D/A converters (12,13,12',13').

Claim 11

Procedure according to claim 5, characterized in that the conversion of said desired rectifier voltages (Ur,Us,Ut) to a stationary coordinate system is performed using one or more D/A converters (15,16).