SU826496A1 - Dc insert - Google Patents

Description

(54) INSERT DC CURRENT

t

The invention relates to a transformative technique and may be used up communications of power systems.

A known scheme for inserting a direct current power supply unit of the power system, co-ordinating limit controlled converters made in a vice bridge circuit, connected to the power systems, and a DC link flj.

A disadvantage of this circuit is that the end converters performing the rectification and inversion of the current consume reactive power from the alternating tOKa network, which reduces the power factor at the dc transfer point (insertion) of the direct current to the power grid. In addition, changing the direction of power flow in such circuits is accomplished by changing the polarity of the poles of the transducers, which, in the presence of a unipolar DC injection, leads to a coronary loss in the corona.

The circuit of the invention is an increase in the power factor of the power systems and a reduction in corona losses in the DC link.

This goal is achieved by the fact that, in the inset, the direct current of the coupling chain of the power systems, which contain end-controlled transducers made in the vice bridge circuit, connected to the power systems, to the DC link, the controllable transducers are equipped with non-controlled open-circuit gates according to the number controllable valves of bridge 1X circuits and connected in parallel with them, and the constant current link is made in the vice filter. The converters are voltage converters, in particular inverters.

In order to reduce losses in the link

Claims (4)

0 DC by reducing the level of harmonics, the phpter is made in the vice U-shaped connection of capacitors and inductive element. 3 The filter may be implemented in the vice hub. With the input harmonic reduction circuit and BbiXLoae, end stations for the stations are equipped with separate converters connected to the main parapeps. FIG. 1 shows a device diagram; Fig. 2 shows graphs of the voltage of the converter, a device circuit diagram and vector diagrams of the operation of the converters in the rectifier and inverter modes. The device matches the AC mains network 1 (power system No. 1), transferers 2 and 3, controlled valve 4 (for example, a thyristor or an electronic auxiliary valve 5, AC network 6 (power system No. 2), voltage converter 7 (for example rectifier), voltage converter 8 (e.g., inverter), filter and DC link 9, filter capacitors 10 and 1, and filter inductive element 12. The device works as follows. When the voltage inverter operates at an autonomous load or idle (iri disconnecting from set and a transformer 3 into a phase converter, a step-shaped voltage is formed (Fig. 2 When the converter is connected to an AC network, the operation mode will be determined from the equivalent circuit of Fig. 23. / As sped from the vector diagrams of Fig. 2 ft and 2 g, under certain The ratios of and,.,;} f and the angle of control of the transducer can work with the extraction of reactive power in the inverter mode (Fig. 2 S), and in the rectifier (Fig. 2 g-). The expressions defining the operational parameters have the video / SG-cC; 3VO, C. where EFD is the amplitude and effective value of the phase current; e 4. - total vector with and | H - angle, which is the characteristic power factor of the converter; P, Q - active and reactive power:, oL - angle between vectors1 and L4 /. The average value of the direct current f -005 () MOUNA analysis of vector diagrams of FIG. 2 expressions (1), (2 shows that; voltage transformer can work in both inverter and output modes | energy conversion can be carried out with the output of reactive power to the power system; changing the direction of transmission of power is accompanied by a change of eye, unlike Traditional transmission schemes. The formula of the network 1.Insertion of direct current dp communication of power systems, including terminal controlled converters made in the form of a bridge circuit, connected to power systems, and DC link, Differing with the fact that, with an increase circuit, the power factor of the power systems and a reduction in corona losses in the DC link, the controlled transducers are equipped with additional uncontrollable vents on the number of controlled bridge circuits and connected in parallel, and the DC link made in the form of fiptra. 2. An insert according to claim 1, so that in order to reduce losses in the DC link by reducing the level of harmonics, the filter is made in the form of a U-shaped connection of capacitors and an in-instrumental design. 3. The insertion device according to claim 1, wherein there, in order to reduce the losses in the DC link by reducing the level of harmonics, the filter is made in the form of a capacitor. , 4. The insertion according to claim 1, characterized in that, in order to reduce the harmonics at the input and output, the terminating converter stations are equipped with additional converters connected with the main parapets. Sources of information taken into account during the examination 1. Possa A.V. Schemes and modes of power transmission of direct current. L., Energie, 1973, p. 12. at one D with n (L