SU547963A1 - Control device for -phase valve converter - Google Patents

Description

The invention relates to converter technology and can be used to control adjustable rectifiers driven by ceTbto inverters and frequency converters with direct coupling and natural switching of valves.

And there are devices for controlling a single-phase converter with a single-gang control system, which contain synchronization pulse shapers, blocks: phase displacement and distribution.

The lack of data from the devices consists in: limiting the adjustment range or introducing a pure delay into the control channel.

Closest to the invention, devices where the phase shift is carried out in a single control channel, which includes a generator of a reference linearly varying signal, a control signal generator, an adder and a zero-organ. The pulses from the output of the comparator start delay circuits for a duration of 2G. / N1, C starts the first delay

the second and so on The pulses from the exit are driven to the corresponding gates of the former.

The known device has a fixed shift between control pulses of different channels, which prevents its use in converters with an output on .-- alternating current (frequency converters with direct coupling)., At a variable frequency of the power supply network, at a high rate of transients, that is, the dynamic properties of the converter are low.

The purpose of the invention is to provide symmetry of pulses of control and improve the dynamic properties of the converter.

Claims (2)

For this, the device for controlling the I1-phase converter is supplied with a constant voltage source and a generator of supergenerate varying shape with height of the amplitude of the reference voltage 1: altering stress The latter is made on the oase of the second source of constant voltage, a ballast resistor, normalized resistors, keys, Jim elements, and an additional null organ, and about the second source of constant voltage are connected via a ballast resistor | m parallel branching consisting of a normalized resistor and a key, the control circuits of the half keys are connected to the output terminals of the generator directly, and the rest of the keys are through elements And, the second inputs of which are connected to the antiphase outputs of the additional culture voltage In FIG. 1 shows the scheme of the proposed device; in fig. 2 (a-d) - timing charts of the device. The device (Fig. 1) contains a reference voltage generator 1, a control signal generator 2, an adder 3, a null organ 4 a distributor 5, a constant voltage source 6 and a voltage generator 7 of a step-varying form. The second source is a constant source .; voltage 8, the ballast resistor 9, the normalized in magnitude resistors are keys 18–25. four elements of type I 26 and an additional null organ of DA. (For definiteness, we consider a transfiguration scheme with a six-pulse output voltage nrt, 6). The vertical control principle of the valve converter is carried out by comparing the magnitude of the control signal and the voltage U (Fig. 2) synchronized by the mains supply .; where i is the number of the converter's gate, the control pulses are generated, at the output of the null organ 4 at the moment of equality of the control signal and the voltage U and for the circuit gates are shown. 2a, the form of a slowly varying control signal is also shown there. In a single-channel control system, the control voltage is compared to one equivalent voltage, made up of voltage segments Uj. Indeed, the voltage Uj can be obtained by summing the sawtooth reference voltage (timing diagram in FIG. 2-b), stepwise / generator voltage (FIG. 2c), and voltage Jforo (FIGURE 2g} the latter is introduced in order to gradually change the voltage to be uni-polar, which is convenient for circuit considerations. The timing diagram of the equivalent capacitance is shown in Fig. 2e, or the generator has a stepwise varying voltage synchronized with the formation of control pulses ventilator and a converter, for which the distributor 5 is connected to the input of a generator of step-varying voltages. The said generator is built along a line of a transformer body to voltage, the output step-changing voltage has a magnitude of steps which is determined by the choice of resistors 10 -17, The voltages U- and U t selected in the diagram of Fig. 2a are formed from different parts of the reference voltage. To maintain continuity of the voltages U and 11, when the reference voltage jumps, the corresponding value changes accordingly step changeable voltage. For this, the polarity of the reference voltage is fixed by an additional null organ 30, and the selection of the generator state by stepwise variable voltage is carried out by a logic circuit consisting of four elements of type AND 26-29. In the circuit realization of the device, control voltage, stepwise varying voltage, as well as voltage source 6, for tiero These voltages are precisely stabilized or these voltages are formed from some voltage UQ so that x magnitude is linearly related to the magnitude of UQ. Thus, the proposed device ke only provides the symmetry of the controllable impulses of the converter, but at the same time provides the best dynamic properties, the potential to work at a varying frequency of the supply mains Fig. 2 b) at high speed transients. The proposed device, for example, can be used in control systems of frequency converters with direct communication. Claim 1 "Device for controlling fn-phase valve converter containing oscillators of a sawtooth n control signal connected through an adder to a zero-body, the output of which includes a valve that is different from A series of pulses of control and a wider range of dynamic properties of a transducer body, it is supplied with a source of constant voltage and a voltage generator of a step & variable shape with a height of steps, the amplitude of the reference voltage related They are connected to the inputs of the adder, and the outputs of the pulse distributor are connected to the generator inputs by stepwise varying voltage. 2. Device pop, 1, characterized in that the alternating voltage generator is made on the basis of the second source of constant voltage of the ballast resistor, normalized. largest resistors, keys, 2. f elements And and an additional null organ, with | - m parallel branches consisting of a normalized resistor and a key, control circuits half of the keys are connected to the second constant voltage source through the ballast resistor the output terminals of the generator j directly, and the rest of the keys through the elements And, the second inputs of which are connected jc anti-phase outputs of an additional zero-orgats connected to the specified reference voltage generator. and , V  4v uS ue i Wa cJt oJji