SU1121740A1 - Device for connecting two power systems - Google Patents

Abstract

A DEVICE FOR COMMUNICATION OF TWO ENERGY SYSTEMS, containing two asynchronized synchronous machines with rigidly connected shafts, the stator windings of which are connected to the appropriate power system, and the rotor windings are connected to the outputs of their excitation controllers, the first, second and third inputs, respectively. the outputs of its voltage and frequency sensors of the power systems and the shaft angle sensor, the fourth input of one of the excitation controllers is connected to The output of the intersystem communication active power sensor, the control input of which serves to receive the reference signal, and the fourth input of the other excitation controller is connected to the output of the slip unit, the inputs of which are connected to the outputs of the angular position sensor of the shaft and the frequency sensors of the connected power systems, that, in order to increase the reliability of the device and reduce its cost, it is additionally equipped with an active power setting unit. the output of which is connected to the control input of the active power sensor, the first input of the active power setting unit serves to receive the reference signal, and its second input is connected to the output of the slip unit, while the active power setting unit contains three potentiometers, five adders, and a key management driver , six locking keys and two disconnecting keys and a product block, the first and second terminals of the first potentiometer being connected via the first and second locking keys to the input of the second meter whose slider is connected to the first input of the first adder, slider L of the first potentiometer is connected via the second adder to the input of a potentiometer, the slider of which is connected to the second input of the first adders whose output is connected to the first input of the third adder, the input and output of the second adder through the third and fourth locking keys K) is connected to the first input of the fourth adder, the second input of which is connected to the second output of the first potentiometer, and the output is connected to the first input of the product, whose output to Connected to the second input of the third cyMijiaTopa, the output of which through the fifth and sixth closing keys is connected to the first input of the fifth adder, the second input of which through the first and second disconnecting keys is connected to the output of the second adder, while the outputs of the first potentiometer are connected to a voltage source, - second block input

Description

product and input shaper of the p adder performed

the key management signals are connected by limiters, is the output

together and form the second input block. block set active power generation active power output.

1121740

The invention relates to electrical engineering for installations for the transmission of electrical energy through AC lines, and more specifically to electrical and mechanical frequency converters for flexible communication of power systems with differing frequencies.

Devices for communication of electric power systems are known, made on the basis of two asynchronous synchronous machines (AFM) with rigidly connected shafts, the stator windings of which are connected separately to power systems, which in the AFM control system contain adjustable frequency converters and field controllers for inputs the signals from the angular position sensors of the aggregate shaft, the frequencies and voltages of the interconnected power systems and from the intersystem communication active power sensor are received. At the output of each excitation controller, a signal is generated with the slip frequency of the rotor, supplied to the input of the thyristor control circuit of the controlled frequency converter. By appropriately controlling the amplitude and phase of the harmonically varying excitation voltage and the compensation of the electromagnetic inertia of the rotor, the power systems are connected with differing mode parameters. However, the frequency of the excitation voltage of each of the AFM. It is supported by the difference, the voltage of the stator and the frequency of rotation of the shaft of the aggregate lj.

A disadvantage of the known device is a reduction in the quality of electric power and a violation of the dynamic stability of the energy connection, since the control parameters of the device use mode parameters that do not sufficiently control the active power flowing through the device.

line voltages and frequencies in an energy-deficient system; and fast oscillation damping in coupled power systems.

Closest to the proposed

device containing two asynchronized synchronous machines with rigidly connected shafts, the stator windings of which are connected to the corresponding power systems, controlled frequency converters, shaft angular position sensor, frequency and voltage sensors of the power systems to be combined, sensor of active power intersystem connection and excitation controllers, while the excitation controller of the AFM, which ensures the maintenance of intersystem overflow of active power, is equipped with integrating and differentiating elements according to active power and voltage, the excitation regulator AFM, providing the specified rotation speed of the shaft of the unit, is equipped with integrating and differentiating elements according to the shaft rotation speed and voltage, as well as the summing element according to the rotation speed, the inputs of the regulators are connected to appropriate sensors, and the outputs to the inputs of their controlled frequency converters. ..

When operating in the power system of communication, such accidents may occur that lead to the disconnection of individual transit sections. Therefore, to control the device for the connection of two power systems, it is necessary to enter additional information into the controllers to control the transmission power. This information is transmitted from the substations via TV channels.

The disadvantage of such a device is the need for these TV channels to transmit additional information about the state of the trans. systolic power line, which generally increases the cost of the device and reduces the reliability of its work when TV channels fail. The purpose of the invention is to increase the reliability of the device and reduce its cost. This goal is achieved by the fact that the device for communication of two energy systems, containing two asynchroniso. Bath synchronous machines with rigidly connected shafts, the stator windings of which are connected to k corresponding power systems and the rotor windings are connected to the outputs of their voltage and frequency sensors through controlled frequency converters to the outputs of their field controllers. energy systems and the angular position sensor of the shaft; the fourth input of one of the excitation regulators is connected to the output of the intersystem communication active power sensor; the control input of the ro This serves to receive the reference signal, and the fourth input of the other excitation controller is connected to the output of the slip unit, whose inputs are connected to the outputs of the shaft angular position sensor and the frequency sensors of the connected power systems, is additionally equipped with an active power reference unit whose output is connected to the Control Input the active power sensor, the first input of the active power reference unit serves as a dp signal reception of the reference, and its second input is connected to the output of the slip block, while the active power reference block contains three potentiometers, five adders, a key management signal generator, six locks and two disconnecting keys and a product block, the first and second terminals of the first potentiometer being connected through the first and second savttKaw keys to the input of the second potentiometer, the slider of which is connected to the first input the first totalizer, the slider of the first potentiometer through the second adder is connected to the input of the third potentiometer, the motor of which is connected to the second input of the first adder, the output of which is connected to the first three input In this adder, the input and output of the second 4P4 math are connected via the third and fourth locking keys to the first input of the fourth adder, the second input of which is connected to the second output of the first potentiometer, and the input connected to the first input of the work unit, the output of which is connected to the second input of the third adder , the output of which is connected through the fifth and sixth with 1 keys to the first input of the fifth adder, the second input through the first and second disconnecting keys is connected with the output of the second; The output of the first potentiometer is connected to a voltage source, the second input of the product and the input of the key management signal generator are connected together and form the second input of the active power setting unit, the output of the fifth adder with limiters is Figure 1 shows the block diagram of the proposed device, figure 2 shows the block diagram of the task of active power / Fig. 3 is a plot of i (5i) implemented in the proposed device Fig. 4 is a diagram of an adder with limiters; Fig. 3 is a graph showing the operation of an adder with limiters. A device for connecting two power systems contains asynchronized synchronous machines 1 and 2 with rigidly connected shafts, the stator windings of which are connected to power systems 3 and 4, and the rotor windings through controlled frequency converters 5 and 6 are connected to the outputs of their excitation regulators 7 and 8, the first, second and third inputs of which are respectively connected to the codes of their voltage sensors 9 and 10 and the sensor 11 of the angular position of the shaft, the fourth input of the excitation regulator 7 is connected to the output of the sensor 12 of the intersystem communication active power, and the fourth input of the regulator 8 of the excitation 8 is connected to the output of the slip block 13, the inputs of which are connected to the outputs of the sensor 11 of the angle shaft and the sensors frequencies of the connected power systems. The inputs of the active power sensor 12 are connected to the power system and from the output of the active power task unit 14, one of the inputs of which is connected to the second output of the slip unit 13. The active power target unit 14 includes potentiometers 15, 16 and 17, adders 18-22, a key management signal generator 23, keys 24-31, and a product block 32. The first and second terminals of the potentiometer 15 through the closing keys 24 and 25 are connected to the input of the potentiometer 16, the sensor of which is connected to the first input of the adder 18, the slider of the potentiometer 15 through the adder .19 connected to the input of the adder 18, the output of which is connected to the first input of the adder 20. The input and the output of the adder 19 through the closing keys 26 and 27 is connected to the first input of the adder 2J, the second input of which is connected to the second output of the potentiometer 15, and the output to the first input of the product block 32, the output of which is connected to the second input of the adder 20 output which via make the keys 28 and 29 is connected to a first input of an adder 22, a second input GoGoG:; f: T "G 30" 3. with the output of the adder 19. The terminals of the potentiometer 15 are connected to a voltage source (not shown), the second input of the product block 32 and the input of the key control signal generator 23 are connected to the output of the split unit 13, the output of the adder 22, made with limiters, connected to the input of the sensor 12 active power. The operation of the device for the connection of two power systems is based on the simultaneous control of machine voltage by the speed of rotation of the atregat shaft and by the flow of active power across the system connection. The device provides the specified power flow in the slip range between the frequencies of the connected power systems the value of the excitation voltage of asynchronized synchronous machines. At the same time, in normal modes, the setpoint P-, ad n ° active power can be represented as a daily graph of the change in power of the power flow through the communication device of two power systems and manually or automatically, or as a function of any system pair, for example, power flow through parallel power lines. The preset device implements the change of the setpoint PI for the power as a function of slip, which is used in emergency operations aAlope s and 5-15AOP, + B, if ISnnAyi iiaA, -5 npeA i1 1 div 82. -151 dop 5 , e-15 | prev,: 1eo1A1Aop if S ,, | PiaA onPi oiA. AOP-1 1 pre, ISiAonl lnpeA iWA Aon-3o.AUon 5 InpeA P r - l5 tipeA Q AlAOn npeA D - - - lelnpeA Ha 2 is shown, the scheme corresponding to this control law in the normal (non-alarm) mode. In this state, the keys are 24,27,28 and 25,26,29 pa, о „к„, ™. and cl. „. 30 and 3, about zhzhitttch plichg / UMW nTTJOtiainl closed. This state corresponds to slip 5, which lies in the operating range of H 1 preA 1 1 1 preA. The potentiometer 15 from the calibrated source receives voltages iUp corresponding to the maximum allowable values of the active power setpoint ilPjaj | (, q). Accordingly, the signal is received from the slider of the potentiometer 15, which corresponds to the specified value of the set value of the chadration of the normal operating voltage. In normal mode, the signal, in the normal mode, inverted twice (in the accumulator inverter 19 and the adder 22) and the passage through the closed keys 30 and 3t, appears with the initial sign at the output of the adder 22 and enters the main control circuit In this way, the specified operating modes of the device are realized by active power, the potentiometer 16 receives signals, IP IPA A through the key 24 or iP JAUon via the key 25, the potentiometer 17 receives a signal - P edd from the inverter 19. The signals those taken from potentiometers 16 and 17 are summed by adder 18. The gain of adder 18 and the potentiometers of 16 and 17 V are respectively chosen in such a way that the ratios are taken: ISnpe | c. | IbUon-151 before p2lcy, 151 dop- | 91 with inequalities. , At the output of the adder 18, a signal B is generated. If the key 24 is closed and 25 is open, then with the key open 24 and closed 25. The adder 21 receives a signal, PI here through the key 27 and the signal through the key 26. The gain of the adder 21 Vy is J / 151 / k p 1 Pre therefore the output of the adder 21 is a signal A, and, if the key is closed 27 and the key is open 26, and with open key 27 and closed 26. The signal A from the output of the sum of the torus 21 is fed to the input of the product block 32, to the other input of which slip signal 5 from block 13 is received. Consequently, at the output of the product block 32, we receive the signal A5i (Te.e. The signal A 5 from the block 32 and the signal B from the output of the adder 18 is summed by the adder 20, the output of which, thus, a signal is generated (A5i + B), as the adder 20 inverts the input signals. This signal through the keys 28 and 29 is fed to the input of the output adder of the circuit 22 and is inverted by it, therefore at the output the sum of the torus 22 forms the signal of the desired sHaica (ASi + B). The necessary logic of the state of the keys is provided by the driver of the 23 seals. The logic of the state of the keys is reflected in the table, where the closed state of the key is denoted by one, and the open state is indicated by zero. . The former 23 can be implemented as a relay unit consisting of two relays, one of which controls the keys 24,27,28 and 30 and has a threshold of 5 | 5 | n (sd, and the other controls the keys 25 , 26,24 and 31 and has a threshold of 5 t- | 5 | np5. Thus, in normal modes, when slip 5 is in the operating range, none of these relays reach the threshold, and the second state of the keys is ensured (see . table). At 5, | e Tsre, the first relay is triggered (the second is far from the response threshold) and the first position of the key is provided uchey (see table). When the first relay is triggered at the output of the adder 22, the dependence P1, A, 9.8 ,, is realized (when the second is triggered, the dependency is HI and PFV (ei), Te P ad PjQAUon at 5.151 to P1 and P1, o | D -1Pk A1dop P 1 p1dd, are formed by a limiter connected to the output adder 22, with levels of restriction i | Pjgj. (. In modes when the slip between the frequencies of the power systems being connected out of the range allowed by the parameters of synchronized synchronous machines of the device for communication of power systems, the block is set and active power provides a change in the setpoint for active power (up to the reverse), which is most conducive to the preservation of both the intersystem communication and the power supply of the cantilever load when part of this communication is disconnected. There is no need for additional teleinformation. This chain increases the reliability of the proposed device for the connection of two power systems. The power setter can be used in devices for the communication of two power systems consisting of both two synchronized synchronized machines and an asynchronized synchronous machine and a synchronous machine, as well as asynchronous synchronous motors and generators. Thus, the technical and economic effect of the application of the proposed device is to use to control the local

information, which reduces 5 beteles. the cost of the device due to the exclusion of TV channels and to increase the reliability of its operation, and consequently, the power consumption of sensors of the fcicmoflw sensors

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Claims (1)

DEVICE FOR COMMUNICATION OF TWO ENERGY SYSTEMS, containing two asynchronous synchronous machines with rigidly connected shafts, the stator windings of which are connected to the corresponding power systems, and the rotor windings are connected through the controlled frequency converters to the outputs of their excitation regulators, the first, second and third inputs of which are respectively connected to the outputs sensors of voltage and frequency of power systems and a sensor of the angular position of the shaft, the fourth input of one of the excitation regulators is connected to the output the intersystem communication active power sensor, the control input of which serves to receive the reference signal, and the fourth input of the other excitation controller is connected to the output of the slip unit, the inputs of which are connected to the outputs of the shaft angular position sensor and frequency sensors of the connected power systems, characterized in that, in order to increase the reliability of the device and its cost reduction, it is additionally equipped with an active power setting unit, the output of which is connected to the control input of the active power sensor, the first input is bl The active power reference window is used to receive the reference signal, and its second input is connected to the output of the slip block, while the active power reference block contains three potentiometers, five adders, a key control signal generator, six closing keys and two disconnecting keys and a product block, the first and second conclusions of the first potentiometer through the first and second closing keys are connected to the input of the second potentiometer, the engine of which is connected to the first (9th input of the first adder, the engine of the first potentiometer and through the second adder connected to the input of the third potentiometer, the engine of which is connected to the second input of the first adder, the output of which is connected to the first input of the third adder, the input and output of the second adder through the third and fourth closing keys are connected to the first input of the fourth adder, the second input of which; connected to the second output of the first * potentiometer, and the output connected to the first input of the product block, the output of which is connected to the second input of the third adder, the output of which through the fifth and sixth closing cells Yuchi is connected to the first input of the fifth adder, the second input of which through the first and second disconnecting keys is connected to the output of the second adder, while the terminals of the first potentiometer are connected to a voltage source, the second input of the unit SU .... 1121740 products and the input of the driver of the key management signals are connected together and form the second input of the active power setting unit, the output of the fifth adder, made by the limiters, is the output of the active power setting unit.