ANALYSIS OF THE FUNCTIONAL CAPABILITIES OF PULSE AC VOLTAGE REGULATORS WITH A COMMON SWITCHING NODE OF VALVE KEYS

The article discusses the functional capabilities of pulse voltage converters with a common switching node for multiple circuits that need to be switched. These converters are divided into two groups: those with bridge switches and those with matrix switches. The operation of the common switching node of thyristors in the input bridge of a single-phase voltage regulator is shown as an example. The analysis of power circuits of both types of single-phase converters showed that using a common switching node provides additional useful properties, such as increasing the speed of voltage regulation with the number of levels greater than the number of thyristor pairs. The presence of a voltage-doubling transformer in the converter structure makes it possible to prevent overvoltage. It is particularly useful to use a common switching node in single-phase wide-band voltage regulators whose power structure is typically based on transformers that operate at both the main and higher frequencies. Due to the double energy conversion, these devices have an increased number of switched valves, so the common switching node significantly improves their performance and allows for regulating the output voltage using both frequency-pulse and pulse-width methods in the range of 0-1 UIN with high quality indicators, reversing the output voltage relative to the network voltage, and combining the functions of a modulator (inverter) and a demodulator in one block. Research on three-phase bridge and matrix converters with a common commutation node has shown that using this power device structure is an effective approach for voltage symmetry when connecting single-phase loads to a three-phase network; for fast switching of backup networks in uninterruptible power supplies; and for direct frequency conversion with the ability to control voltage and reactive power.