CS260751B1 - Transistor frequency converter for dynamically variable four-speed drives - Google Patents

Abstract

The transistor frequency converter for dynamically demanding four-quadrant drives is designed to power single- or three-phase asynchronous or synchronous motors in dynamically demanding regulated electric drives. The converter contains two three-phase diode and two three-phase transistor bridges. The interconnected alternating sides of one diode and one transistor bridge form the input, respectively. output of the frequency converter and the interconnected direct current sides of one diode and one transistor bridge form two separate inertia-free direct current intermediate circuits.

Description

260751 3 4

The invention relates to a transistor transducer for frequency-intensive quadrant drives for powering single- or three-phase asynchronous or synchronous motors for regulated drive systems with high system performance requirements.

Previously known wiring of static frequency converters are both expressed as a one-way intermediate circuit and without a one-way intermediate circuit, i.e. a direct converter. The unidirectional intermediate circuit can be a voltage or current type, depending on whether it contains a capacitor or a choke. The considerable interconvention time constant is the reason that these connections cannot meet the highest dynamic requirements that are required for the most demanding regulated drives. A DC-to-voltage converter must have an anti-parallel pair of rectifiers at the input. .for recreation, energy feathering. On the other hand, the prior art sinusoidal frequency converter of the required frequency converter requires three pairs of electronic switches formed by a series combination of a diode and a power transistor for the two-phase connection of the inverter to each phase of the three-phase input system; for a three-phase output, "a total of eight, a set of such switches, in addition, the control circuits of such a transducer must contain, among other things, enough" oscillators ", ie, an input voltage decoder for detecting the input phase that has the most costly in the eye , respectively. the most negative potential. Based on its output code and other logic signals, the decoding logic determines the transistors to be excited in the control portion of the transducer.

The essence of a transistor frequency converter for dynamically demanding quadruple drives is that both the first diode bridge with the first transistor bridge and the second diode bridge with the second transistor bridge, the cathode node of the first diode bridge, are connected by alternating current transducers. coupled to the collector node of the second transistor bridge -aq. the cathode node of the second diode band is connected to the collector node of the first transistor bridge. A similar anode node of the first diode bridge is connected to the emitter node of the second transistor bridge, respectively. the cathode node of the second diode bridge is connected to the emitter node of the first transistor bridge. The input and output of the converter is on mutually interconnected alternating sides of the bridges.

In contrast to the previously known circuitry, the number of controlled power semiconductor devices decreases. The control circuitry logic of the present invention is much simpler than the prior art wiring diagrams.

In the drawing, a specific connection of a three-phase transistor converter and frequency for dynamically demanding four-pass drives according to the invention is shown.

An alternating side of the first three-phase clock bridge 1 and an alternating side of the first three-phase transistor bridge 2 are connected to the input terminals 1L1, 1L2, 1L3. The alternating side of the second three-phase transistor bridge 4 is connected to the output terminals 2L1, 2L2, 2L3. and alternating the second three-phase diode bias 3. The cathode node of the first three-phase clock bridge 1 is coupled to the collector node of the second transistor bridge 4, and the anode node of the first diode bias 1 is coupled to the emitter node of the second, three-phase bias. transistor bridge4. The emitter node of the first three-phase transistor bridge 2 is connected to the anode of the second three-phase diode mosquito 3 and the electric node of the first transistor bridge 2 is connected to the cathode exchange of the second three-phase diode mosquito 3.

The first uncontrolled three-phase diode brass 1 always connects the most expensive inlet phase to the collector node, respectively. the most negative phase to the emitter node of the second triple phase transistor bridge 4, which the power semiconductor components of the desired algorithm connect to and disconnect the most expensive and negative phase of the output terminals 2L1, 2L2, 2L3 of the frequency converter. After switching off the transistor of the second current-phase transistor bridge 4 of the current-disconnected phase belonging to the output terminal, it switches from the switched-off transistor through the second three-phase diode bridge 3 to the excited transistor of the first three-phase transistor bridge 2.

Claims (1)

Transistor frequency converter for dynamically demanding four-quadrant drives, characterized in that the input terminals (1L1, 1L2, 1L3) are connected alternating side of the first diode bridge (1) and simultaneously alternating side of the first transistor bridge (2) and output terminals (2L1, 2L2, 2L3), the alternating side of the second transistor bridge (4) and the alternating side of the second diode bridge (3) are connected, wherein the cathode node of the first diode bias (1) is connected to the collector node of the second transistor bridge (4) and anode node of the first the diode bridge (1) is connected to the emitter node of the second transistor bridge (4), while the emitter node of the first transistor bridge (2) is connected to the anode node of the second diode bridge (3) and the collector node of the first transistor bridge (2) is connected to the cathode node of the second diode bridge (3).