Novel highly integrated current measurement method for drive inverters

Abstract

Measuring the load current of drive inverters is still inevitable for a precise current control. In common industrial and automotive inverters hall effect based current sensors are widely used.[1] The presented novel current measurement method is based on an inductive current sensor like a Rogowski coil. This can be fabricated much smaller and cheaper than hall based current sensors and can be integrated into drive inverter systems easily. Unlike u evaluation electronic for Rogowski coils, AC and DC components of the load current can be measured using a special evaluation scheme. The arrangement of the sensors also allows them to be used for fast short-circuit detection and di/dt me that some synergies with the gate drive circuitry can be used to create a more compact and reliable system.

A Review of Megahertz Current Sensors for Megahertz Power Converters

“…Also, as mentioned before, the biggest disadvantage of a traditional RCCS is its inability to measure a DC. Therefore, for control purposes, an appropriate programming algorithm must accompany the RCCS to allow it to measure a DC [139]- [140]. Fig.…”

Structure and modelling of four‐layer screen‐returned PCB Rogowski coil with very few turns for high‐bandwidth SiC current measurement

“…The same measurement can be performed with a PCB Rogowski coil instead for a higher power density [6,7,[17][18][19][20][21][22][23][24][25]. One possible PCB coil wound with short tracks and vias is shown in Fig.…”

“…Consideration 3: Parameters R 0 and C 0 should be chosen, so that R 0 C 0 = R 1 C 1 , which is also a condition imposed on consideration 2 and for earlier simplification of (16) and (17) for the ideal noninverting integrator. Consideration 4: Parameters R h and C h should be chosen according to (22).…”

“…Fig. 1 shows a basic RCS [6–8, 10–20, 22, 23] for measuring current i ( t ) flowing through a conductor surrounded by a helical coil. Terminal voltage v i ( t ) induced in the coil is proportional to the rate of change of i ( t ).…”

“…Such accuracy has not been demonstrated in the literature. For comprehensiveness, the prospective passive [22] and active [6][7][8][13][14][15][16] integrators for regenerating the desired current waveform from the four-layer Rogowski coil have also been described. The eventual solution identified is a modified noninverting integrator, whose wide range of integration and lack of DC offset, pre-shoot and distorted droop problems have promptly met demands of the coil.…”