Predictive Control of Three Phase AC/DC Converters

Chapter 6
Experimental Study
Experimental studies were performed on the laboratory set-up, which consists of
an AC/DC voltage source converter (Danfoss VLT 5005 5 kVA), AC-side choke,
and control system implemented on dSPACE 1103 board. Main data of the power
circuit are summarized in Tab. 6.1. As a supply, a programmable power simulator
has been used, which guarantees sinusoidal voltage waveforms. Note that all tests
have been carried out with reduced line voltage amplitude.
Quantity
Value
Fundamental Frequency F L [Hz] 50
Supply Voltage u L(RMS) [V] 120
VSC max. current i L(RMS) [A] 8
Input Filter Inductance L [mH] 10
Input Filter Resistance R [mΩ] 100
DC-link Capacitance C [µF] 470
Table 6.1: Main data of laboratory set-up
6.1 Steady State Operation
Presented control methods have been divided into two main groups: with variable
(like: ST-DPC and VSF), and constant or fixed switching frequency (like: DPC-
SVM and CSF), and further compared under steady state operation. To avoid
DC voltage control loop influence, all tests have been carried out with open loop,
and under unity power factor condition Q ref = 0. The reference value of active
power P ref has been set to 2 kW, and the DC side load resistance has been set to
100 Ω. Table 6.2 summarizes sampling frequencies F s , and achieved line current
T HD factors for investigated methods.
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