SU681534A1 - Arrangement for automatic synchronous machine field control - Google Patents

Description

one

The invention relates to the field of electric power industry, in particular, to devices for automatic regulation of the excitation of synchronous machines.

Automatic excitation controller. (ARV) is an integral part of the excitation system of large synchronous generators.

APB is known in which the three-phase generator voltage received from the transformer is summed with the voltage received from the transformer, combined with a voltage proportional to the generator's reactive current (current compensation), rectified, filtered, compared with the reference voltage from the stabilizer with a temperature compensated Zener diode and amplified by an op amp. The amplified signal is fed to the input of the thyristor converter (controlled exciter). For the oscillation damping, a system stabilizer is provided - control by changing the frequency and its first derivative l.

The ARV is also known in which it is regulated (in 10 modes it is carried out by the generator voltage deviation with the introduction of an additional component of the generator reactive current to compensate for the voltage drop in the step-up transformer. To stabilize the system, the operational amplifier is covered by a complex type active-capacitive circuit Feedback. To increase the reliability of the generators when working in overload modes, as well as

The most common use of the capabilities of synchronous machines for the consumption and generation of reactive power of the ARV is equipped with rotor and stator current limiters and angle limit 2.

The closest in technical essence to the proposed device is a unified high-potency antiretroviral therapy, in which the blocks detecting voltage and frequency deviations are connected to the generator voltage by their inputs, and outputs through the proportional-differentiating blocks to the input of the summing amplifier. The output of the amplifying amplifier is connected to the input of the controlled exciter and through a feedback unit to its own input. Three-phase generator voltage

0 according to the regulation scheme summarizes;

with a voltage proportional to the reactive current, is rectified, filtered, and then fed to a balanced non-linear bridge (an evolving element of the voltage deviation). From the output of the non-linear bridge, a signal proportional to the voltage deviation is applied to the input after amplification (summing amplifier) pathogen control systems,

However, known APBs differ in the limiting range of statism settings, which is due to the high and low frequency gain control adjustments in the voltage channel and the instability of the static characteristic due to the drift of the voltage channels and frequency.

In addition, their structure does not allow to resolve the contradiction between the requirements of high speed of VIY and static accuracy.

The aim of the invention is to increase speed, static accuracy and expand the range of voltage regulation statism settings.

This is achieved by the fact that the proposed device for automatic regulation of the excitation of a synchronous machine, comprising blocks for detecting voltage deviations and frequencies, proportional-differentiating blocks, a summing amplifier and a feedback unit, the outputs of the blocks for detecting voltage deviations and frequencies are connected proportional-differential units with a summing amplifier, and the input of the feedback unit is connected to the input of the summing amplifier, equipped with a proportional-integrating amplifier and a unit -frequency compensation, the output proportsionalnointegriruyuschego amplifier coupled to the input of the summing amplifier, and input - with blocks vyhodagli detecting deflection voltage and feedback and through the frequency compensation unit - to the output of frequency error detection.

To further increase speed and accuracy, the voltage deviation detection unit contains a fast-acting% i precision element, with the output of the fast-acting element connected to the proportional-differentiating unit and the precision output to the input of the proportional-integrating amplifier. To further increase the fastness and noise immunity, the output is proportional to the integrating amplifier is connected to the adder via a fast acting element of the block for detecting voltage deviation and proportional diff Receiving unit.

FIG. 1 shows a schematic of the proposed device for automatically controlling the excitation of a synchronous generator; in fig. 2 - the same, but with a voltage deviation detection unit made using high-speed and cyclic elements; FIG. 3 - the same, but with a different connection of the proportional-integrating amplifier.

The device contains a voltage setting unit 1, connected to the input of a voltage deviating unit 2, and a frequency deviation detection unit 3, 3, and a voltage deviation detection unit 2, connected through a proportional-differentiating unit 4 and J to the input of summing amplifier 6, acting on the exciter with the control system 7. The feedback unit 8 is connected from the output of the summing amplifier 6 to the input of the proportional-integrating amplifier 9; The frequency compensation unit 10 is switched on from the output of the deflection detection unit Ota proportional to the input of the integrating amplifier 9.

The device works as follows.

With rapid changes in the regulated voltage, the device operates in a manner similar to that known. At low frequencies, a proportional-integrating amplifier comes into operation. Since the voltage deviation signal and the regulator output signal supplied through the feedback unit are compared at its input, it provides the specified static characteristic with high current. To eliminate the influence of a proportional-integrating amplifier on the effectiveness of a stabilizing effect in frequency, a signal proportional to a change in frequency is fed to its input through a special device. The speed and accuracy of the voltage control of such a device is determined entirely by the capabilities of the measuring element.

It is fundamentally impossible to build a voltage deviator with high speed and at the same time high static accuracy,

Claims (3)

In order to further improve the speed and accuracy of the adjustment, the voltage block contains a fast-acting element 11 and a precision element 12, with the output of the fast-acting element connected to the proportional-differentiating unit and the precision output to the input of the proportional-integrating amplifier. Such a device with a large fast action reacts to a change in the regulated voltage and, at the same time, can regulate with any statistic, even astatic. Since the gain of the integrating amplifier at a low frequency is very important, a predetermined control statistic is provided with high accuracy. To increase the steepness of the high-speed sizing device (which allows increasing the speed of the controller by reducing the constant time on the voltage channel) in the device, the output of the proportional-integrating amplifier is connected to the adder via the high-speed element of the unit and the proportional-differentiating unit. The proposed device is simple in design and technological, it is made on non-deficient standard elements of wide application. It is characterized by the ability to regulate with any statism, even to static, an increase in the accuracy of voltage regulation by about an order of magnitude, an increase in the speed of voltage regulation no less than three times. At the same time, the maximum net lag does not exceed half the period of the regulated voltage. Pulsations along the voltage regulation path are reduced by about an order of magnitude. Claim 1. Device for automatic regulation of excitation of a Sikhroynaya machine, containing blocks for detecting deviations in frequency voltage, proportional-differentiating blocks, summing amplifier and feedback unit, with outputs of blocks for detecting voltage deviations and frequencies connected in proportion to -differentiating units with a summing amplifier, and the input of the feedback unit is connected to the input of a summing amplifier, characterized in that, in order to improve speed, accuracy and expansion the range of statistical settings, it is equipped with a proportional-integrating amplifier and a frequency compensation unit, the output of the proportional-integrating amplifier is connected to the input of the summing amplifier, and the input is connected to the output of the frequency deviation detection units. 2. Device pop. 1, characterized in that, in order to further improve performance and accuracy, the voltage deviation detection unit contains a fast-acting and precision element, and the output of the high-speed element is connected to the proportional-differentiating unit, and the output of the precision one is proportional to the input -integrating amplifier. Sv device on PP. 1 and 2, characterized in that, in order to maximize the speed and noise immunity, the output of the proportional-integrating amplifier is connected to the adder via a high-speed element of the voltage deviation detection unit and the proportional-differentiating unit. Sources of information taken into account in the examination 1.KlayF.W., South W.H. And solidstate regulatoj vor electric ufility applications IEEE Trans. Power Appar. and Syst., 1971, V 90 N 4. 2.Peneder F. Unirol-Regler als Spannungler fur Generatoren Brown Boveri Hitt., 1969, 56 (f 9 3. Automatic high-field excitation controller for hydrogenerators, turbo-generators and synchronous compensators, unified. Technical description and operating instructions. M., VEI them. Lenin, 1970.