Device for consumer voltage form conversion

FIELD: electricity.

SUBSTANCE: invention is attributed to electric engineering. For this purpose the device contains compensating block, control system, voltage sensing device and current transformer at that the compensating block includes device for alternating voltage component calculating, comparing element, delta modulator and self-commutated voltage inverter. Power unit consists of converter transformer, thyristor bridge and engine. Primary winding of voltage sensing device is connected between network and "ground", secondary winding of voltage sensing device is linked with input of alternating voltage component calculating device and the second input of compensating block comparing element. Primary winding of current transformer is connected between the network and primary winding of converter transformer, secondary winding of current transformer is linked with output of self-commutated voltage inverter of compensating block. Output of control system is connected with the second input of thyristor bridge.

EFFECT: providing maximisation of device operation stability, increase of electric locomotive power and increase of its travelling speed.

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The invention relates to electrical engineering and is intended to reduce the ripple voltage consumers, having in its composition a rectifier-inverter converters, in particular for electric rolling the composition of the AC.

Currently, the railway network AC most widely locomotives with zone-phase voltage regulation on traction engines. These locomotives is accompanied by a significant distortion of the network voltage, which are connected with the processes of switching converters. Start switching causes a sharp decrease in the voltage at the pantograph of the locomotive. However, the instant stress relief does not occur because of the presence in the contact network of distributed inductance and capacity, there are free of voltage fluctuations. Similar processes occur in the end switching, resulting in the pantograph of the locomotive are formed free postcomputation voltage fluctuations. Thus, distortion of the waveform of the supply voltage by free voltage fluctuations that occur at the start and end of switching. The amplitude of these oscillations are determined by the jump forced voltage at the start and end of switching. In% the SSE switching on the pantograph of the locomotive are not only free of voltage fluctuations, but the currents.

One of the ways of reducing free of voltage fluctuations and, accordingly, improving the shape of the mains voltage is raznorazne control of the two converters of the locomotive. He is the separation in time of beginnings and endings switching to different groups of transducers, which reduces the races forced voltage at the beginning and end of the interval switching. Due to this reduced amplitude postcomputation voltage fluctuations and, accordingly, improves the shape of the voltage at the pantograph of the locomotive.

A device for transformation of the form of the voltage of the consumer that is installed on the locomotive VL-001 [1], which used the principle raznoraznog voltage regulation. The known device consists of two control channels, the source managed impulses and delay unit. Each of the channels of the regulation contains a Converter transformer, controlled rectifier, amplifier and pulse distributor.

The primary winding Converter transformers are connected to the network, and their secondary windings connected to series-connected controlled rectifier, an amplifier and a pulse distributor. The source of control pulses connected to the input of the pulse distributor of the first channel and through the block is Ameriki - with the input of the pulse distributor of the second channel.

The device operates as follows. The control pulses from a source of control pulses through the pulse distributor and amplifier arrive at the controlled rectifier of the first channel directly, and the controlled rectifier of the second channel is through the distributor pulses, the amplifier and the delay unit. Due to this, the signal source of control pulses, comes after some time at the input of the second control channel, providing a delay time in the process of switching the second control channel. Since the switching processes in the first and second channels regulation spaced in time, decreases the magnitude of the jump forced voltage and amplitude of the free high-frequency voltage fluctuations. The delay unit delays the opening of the thyristors of the rectifier of the second block on the value of the half-period free of high-frequency voltage fluctuations. In this case, since the second half with the addition of the high frequency ripple voltages of the channels on the pantograph of the locomotive reached the highest compensation of high-frequency voltage fluctuations and approximation of the shape of the voltage at the pantograph sinusoidal shape.

Thus, sequential switching, implementing tulaema due to the delay of the opening of the thyristors of the rectifier of the second control channel, reduces races forced voltage and the amplitude of the free oscillations of the voltage at the pantograph of the locomotive. The coefficient waveform of the supply voltage approaches the shape factor of the sine wave that increases the stability of the control equipment.

Another advantage of this device is to increase the capacity of the locomotive. This is due to the fact that the compensation of the ripple voltage at the pantograph causes the reduction of the ripple of the rectified voltage to the traction motors of the locomotive. The reduction of the ripple of the rectified voltage, in turn, leads to a loss of voltage in the circuit of the rectified current and, consequently, to increase the level of voltage on the motors of an electric locomotive. Increasing the voltage at the motors causes an increase in the power of a locomotive.

However, the device raznoraznog control is not fully ensures the stability of the control equipment and the increasing power of the locomotive, which is a disadvantage of the known device. This is because the decrease in free switching voltage fluctuations on the pantograph of the locomotive is only partially due to the fact that the available voltage fluctuations that occur when switching converters, are fading nature. When the sum of these is Alsace on the pantograph of the locomotive first half-wave of high frequency ripple voltage of the first Converter is not compensated by the pulsation of the second Converter. In the future there will be compensation half-wave high-frequency voltage fluctuations of different transducers with different amplitude. In this regard, in the curve of the voltage at the pantograph of the locomotive remain uncompensated high-frequency ripple voltage, worsening his condition. The deterioration of the shape of this voltage reduces the stability of the control equipment and reduces the capacity of the locomotive.

Closest to the claimed solution of the essential features and the achieved result is a device for converting the form of the voltage of the consumer, based on the compensation of high-frequency switching current fluctuations [2].

A device for converting the form of the voltage of the consumer contains the compensation unit, power unit, control system and sensor voltage having primary and secondary windings.

The compensation unit comprises sequentially enabled devices calculate the variable component of the voltage comparison element, the Delta modulator and four-quadrant Converter (current source compensation).

The input of the calculation of the variable component of voltage is the input of the compensation unit, and the output of the four-quadrant Converter is its output. The output of the calculation of the variable component on the suppressors connected to the input of the comparison element, a second input connected to the input of the calculation of the variable component of the voltage.

The power unit includes a Converter transformer, thyristor bridge and the engine. The primary winding of the Converter transformer is the input of the power unit, and its secondary winding connected to the input of the thyristor bridge. The output of the engine is grounded.

The input of the compensation unit is connected to a secondary winding of the sensor voltage, the primary winding is connected between the network and ground. The output of the compensation unit is connected to the secondary winding of the Converter transformer. The control system is connected with the second input of the thyristor bridge.

The device operates as follows. The alternating voltage supplied to the primary winding of the Converter transformer. Thyristor bridge converts the AC voltage of the secondary winding of the Converter transformer in adjustable constant voltage supplied to the motors. While the pulses of the control system to regulate the level of voltage supplied to the engines.

The signal from the secondary winding of the sensor voltage, proportional to the line voltage (the voltage at the pantograph of the locomotive), is fed to the input of the calculation of the variable component of voltage. Eliminate the CTB calculation of the variable component of the voltage of the highlights of the signal voltage of the first harmonic component, which coincides with moments of natural transition voltage through zero. The comparison element calculates the difference between the current value of the voltage at the pantograph and its first harmonic, the result at the output of the comparison element is formed by a signal proportional to the high-frequency ripple voltage at the pantograph of the locomotive. This signal is converted Delta modulator is fed to the input four-quadrant Converter, which generates in the secondary winding of the Converter transformer high frequency harmonic current that is proportional to the high-frequency ripple voltage on the current collector. Generated on nekommutativnyj time intervals of high-frequency harmonic current is passed to the primary winding of the Converter transformer, where she antiphase is free of high-frequency current oscillations that occur during switching. Thus, the generated nekommutativnyj intervals current harmonics lead to compensation of the free oscillations of the current and, accordingly, to improve the shape of the voltage at the pantograph of the locomotive. This prevents the development process of the free oscillations of current and voltage in the primary winding of the Converter transformer (the pantograph of the locomotive). During the process to the mutation, occupying a considerable part of the working time, the secondary winding of the Converter transformer is shunted by open thyristors thyristor bridge [3]. Since the output of the four-quadrant Converter compensation unit is also connected to the secondary winding of the Converter transformer, while switching its output is shorted and the voltage at its output becomes zero. For this reason, the intervals of the switching at the output of the compensation unit no harmonic current generated in the secondary winding of the Converter transformer. Accordingly, no compensation of the free oscillations of voltage and current in the primary winding of the Converter transformer. Because of this, in the control equipment of locomotive failures remain, and the power of the locomotive is not implemented in full.

Compensation of high-frequency ripple voltage in the primary winding of the Converter transformer on nekommutativnyj intervals leads to increased capacity and trouble-free operation of a locomotive.

However, the known device does not fully provide improved forms of stress, as during switching on the pantograph of the locomotive remains distortions caused by the absence at this time, current compensation, GE is erasemode block compensation (figure 2,a). Uncompensated high-frequency ripple voltage at the pantograph will not allow you to fully realize the power of the locomotive and to increase the stability of the operation of his equipment.

The problem solved by the invention is the development of devices for the conversion of the form of the voltage of the consumer for maximising the sustainability of its work, the increasing power of the locomotive, as well as increasing the speed of its movement by eliminating distortion of the voltage at the pantograph on the entire operating time interval including the interval switching.

To solve this task, the device for converting the form of the voltage of the consumer containing the compensation unit, including serial connected device calculating the variable component of the voltage, the element of comparison, the Delta modulator and a current source compensation, power block, which includes serially connected rectifier transformer, thyristor bridge and the engine control system and the sensor voltage having primary and secondary windings, with the input of the calculation of the variable component of voltage is the input of the compensation unit, and the output of the current source compensation - its output, the primary winding of the Converter transformer is vodomirova block, the output of the engine is grounded primary winding of the sensor voltages included between network and ground, its secondary winding is connected with the input of the calculation of the variable component voltage and the second input of the comparison element of the compensation unit, and the output of the control system is coupled to a second input of the thyristor bridge is further provided with a current transformer as a current source compensation the selected Autonomous voltage inverter, with the primary winding of the current transformer is connected between the network and the primary winding of the Converter transformer and the secondary winding is connected to the output of the Autonomous inverter voltage compensation unit.

Introduction voltage transformer, the choice of Autonomous voltage inverter as a source of current and new relationships of elements in the device compensation provide the maximum increase in power and reliable operation of the locomotive. This is due to the fact that current compensation is generated by the compensation unit during all working hours, including the interval switching in the power block. Due to the fact that a current loop compensation taken out of circuit switching, and through him, at the time of switching does not leak the short circuit current and there are no restrictions on the formation of current compensation on the switching intervals. Talk to what pensatore generated during the working interval, including the switching intervals. Because the compensation of high-frequency current is produced across the whole working interval of time, this leads to a full compensation of high-frequency voltage at the pantograph of the locomotive and, consequently, to an approximation of its shape to a sine wave (figure 2,b).

In addition, the full compensation of high-frequency current increases the speed of a locomotive that is not obvious from the prior art. Compensation of high-frequency current decreases the voltage losses in the inductive resistance of the contact network and a corresponding increase in voltage at the pantograph of the locomotive. The increase in the voltage at the pantograph of the locomotive increases the speed of its movement.

Figure 1 shows the diagram of the inventive device.

Figure 2 presents the form of voltage at the pantograph of the locomotive with the smooth control voltage (2 and for prototype 2,b - for the claimed device). From figure 2 it is seen that when the locomotive with the claimed device (curve b) in the form of voltage at the pantograph no distortions associated with switching processes.

A device for converting the form of the voltage of the consumer contains the compensation unit 1, the power unit 2, the control system 3, the sensor voltage is s 4 and the current transformer 5.

The compensation unit 1 includes a serial connected device calculating the variable component of the voltage 6, the comparison element 7, the Delta modulator 8 and the current source compensation 9. As the source current compensation 9 used Autonomous voltage inverter. The input of the calculation of the variable component of voltage 6 is the input of the compensation unit 1, and the output of the Autonomous voltage inverter 9 is its output.

Power block 2 consists of series-connected Converter transformer 10, the thyristor bridge 11 and the motor 12. The primary winding of the Converter transformer 10 is the input of the power unit 2, the output of the engine 12 is grounded.

The primary winding of the voltage detector 4 is included between network and ground, the secondary winding of the voltage detector 4 is connected with the input of the calculation of the variable component of voltage 6 and the second input of the comparison element 7 compensation unit 1. The primary winding of the current transformer 5 connected between the network and the primary winding of the Converter transformer 10, the secondary winding of the current transformer 5 is connected to the output of the Autonomous voltage inverter 9 compensation unit 2. The output of the control system 3 is connected to a second input of the thyristor bridge 11.

Thyristor bridge made on the basis of power Tiesto the s type TL 830, the control system is implemented on the basis of logic elements, the average degree of integration, Autonomous voltage inverter is assembled from the power fully managed IGBT transistors, a basis of calculation of the variable component of the voltage and the Delta modulator comprise operational amplifiers series COD.

A device for converting the form of the voltage of the consumer operates as follows. The signal from the secondary winding of the voltage detector 4, is proportional to the voltage (the voltage at the pantograph of the locomotive), is fed to the input of the calculation of the variable component of voltage 6. The device calculate the variable component of the voltage 6 highlights of the signal voltage of the first harmonic component, which coincides with the natural moments of transition voltage through zero. The comparison element 7 calculates the difference between the current value of the voltage at the pantograph and its first harmonic, the result at the output of the comparison element 7 is formed by a signal proportional to the high-frequency ripple voltage at the pantograph of the locomotive. This signal is converted Delta modulator 8, is fed to the input of the Autonomous voltage inverter 9, which generates the secondary winding of the current transformer 5 high-frequency harmonic current, proportional the Yu high-frequency ripple voltage on the current collector. The generated high-frequency harmonic current is transmitted to the primary winding of the current transformer 5, where it antiphase is free of high-frequency current oscillations that occur during switching. The generated current harmonics lead to compensation of the free oscillations of the current and, accordingly, the voltage at the pantograph of the locomotive. This prevents the development process of the free oscillations of current and voltage in the primary winding of the Converter transformer (the pantograph of the locomotive). Compensation of high-frequency ripple voltage results in improved shape of the voltage at the pantograph of the locomotive.

Due to the fact that the current-loop compensation of high-frequency ripple current drawn from the circuit switching during switching does not leak the short circuit current and there are no restrictions on the formation of current compensation on the switching intervals. The current compensator is generated over the entire operating range, including the switching intervals. Because the compensation of high-frequency current and voltage occurs across the whole working time interval including the interval switching, the shape of the voltage on the current collector is improved and the switching intervals, approximating to a sinusoidal form. Since the pulses upravleniemoeda in accordance with the form of voltage, when the operation of the control system of the locomotive with the improved form of voltage at the pantograph failures are excluded. The reduction of ripple voltage in the rectifier current circuit and increase its effective value of the maximum increases implemented by the locomotive power.

The use of devices to convert the form of the voltage of the consumer allows to increase the voltage at the pantograph of the locomotive by 3.8% and to increase its capacity by 2.7%.

Sources of information

1. Hummelink and other Tests of locomotive VL with ratnofsky running rectifier-inverter converters. Bulletin of VNIIZHT, 1986. No. 4, p.23-26.

2. Hummelink, Uscable. The improved shape of the voltage at the pantograph of the locomotive AC. Proceedings of all-Russian scientific-practical conference of scientists transport, Universities, research institutes, engineers and representatives of academic science. Volume 1. Chita, - 2006. s-246.

3. Hummelink. The structure and operation of a rectifier-inverter. Locomotive - 2001. No. 1, p.14-18.

A device for converting the form of the voltage of the consumer containing the compensation unit, including serial connected device calculating the variable component of the voltage, the element of comparison, the Delta modulator and a current source compensation, power block, SOS is Oasi of series-connected Converter transformer, thyristor bridge and engine control system and the sensor voltage having primary and secondary windings, with the input of the calculation of the variable component of voltage is the input of the compensation unit, and the output of the current source compensation - its output, the primary winding of the Converter transformer is the input of the power unit, the motor output is grounded, the primary winding of the sensor voltages included between network and ground, its secondary winding is connected with the input of the calculation of the variable component voltage and the second input of the comparison element of the compensation unit, and the output of the control system is coupled to a second input of the thyristor bridge, characterized in that it added a current transformer as a current source compensation the selected Autonomous voltage inverter, with the primary winding of the current transformer is connected between the network and the primary winding of the Converter transformer and the secondary winding is connected to the output of the Autonomous inverter voltage compensation unit.



 

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