JPH0688509B2 - Control method and apparatus for regenerative inverter for electric railway - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

A. Industrial field of use B. Outline of invention C. Prior art D. Problems to be solved by the invention E. Means for solving the problems F. Action G. Example G ₁ .1st implementation Example (Fig. 1) G ₂ .Second embodiment (Fig. 2) H. Effects of the invention A. Industrial field of application The present invention is a converter for supplying DC power to the trolley line of a DC feed electric railway. The present invention relates to a regenerative substation system including an inverter that regenerates regenerative electric power generated by an electric vehicle that can be regeneratively controlled to an AC power supply side, and more particularly, to a control method and apparatus for a regenerative inverter for electric railway.

B. SUMMARY OF THE INVENTION The present invention provides a control method and apparatus for a regenerative inverter for electric railways, which detects a converter current, an inverter current, and an electric line voltage, and provides the detected electric quantity and a preset predetermined electric quantity. In addition, the converter input voltage fluctuations are configured even when the electric vehicle is in the power running mode by configuring the automatic line voltage adjustment system to correct the electric line voltage based on the deviation output obtained by the above matching. In this way, the inverter can be surely brought into the operating state regardless of the above, and the circulating current flowing in the inverter can be always suppressed to the minimum level.

C. Conventional Technology Generally, a regenerative substation system is constructed as shown in Fig. 4, for example. In FIG. 4, the output power of the AC power supply 1 is input to the converter 3 configured by bridge-connecting the diodes via the transformer 2a. The converter 3 converts the input AC power into DC and supplies the DC power to the electric vehicle 6 via the DC high-speed circuit breaker 4 a and the train line 5. The regenerative electric power generated during the regenerative operation of the electric vehicle 6 is input to the inverter 8 configured by bridge connection of thyristors via the DC high-speed circuit breaker 4b and the DC reactor 7. The inverter 8 converts the input DC power into AC, and regenerates the AC power to the AC power supply 1 via the transformer 2b.

In the device configured as described above, the operation control of converter 3 and inverter 8 is performed as shown in the voltage-current characteristic diagram of FIG. 5 in accordance with the change in voltage Ed of train line 5. That is, when the electric vehicle 6 is in the powering operation, the converter 3
When only DC current is Id, the voltage Ed of the electric power line 5 at that time changes as shown in the region I of FIG. Further, when the electric vehicle 6 performs regenerative braking, the voltage Ed of the electric train line 5 rises, and when the voltage Ed exceeds the regenerative set voltage, an inverter control circuit (not shown) drives the inverter 8
The operation of is started. Then, the inverter 8 is subjected to constant voltage control by the inverter control circuit so as to keep the voltage Ed of the electric line 5 at the electric line voltage Vd ₀ at the time of regeneration as shown in the regeneration operation area II of FIG.

D. Problems to be solved by the invention In the regenerative substation system configured as described above,
When the no-load DC voltage of the inverter is set lower than the maximum train line voltage Vd (no-load DC voltage of the converter) during power running, an excessive circulating current flows between the converter 3 and the inverter 8 due to fluctuations in the converter input power supply voltage. Will end up. Therefore, as shown in Fig. 5, the regenerative set voltage Vd ₀ is the maximum train line voltage Vd during power running (the no-load DC voltage of the converter).
Had to set higher. However, in such a setting, even if the electric vehicle 6 performs regenerative braking, the inverter 8 remains in a standby state until the train line voltage reaches the regenerative set voltage from the maximum train line voltage Vd during power running. To do. Therefore, the regenerative electric power generated by the electric vehicle 6 cannot be regenerated, and thus the regenerative electric power cannot be effectively used. In particular, when the rise of the regenerative current during regenerative braking is fast and the operation of the inverter 8 is delayed as described above,
The voltage Ed of the train line 5 rises abnormally. For this reason, the electric vehicle 6 cannot use the regenerative brake, and must stop using the air brake or the like after tripping the circuit breaker on the electric vehicle side.

Further, the following inverter control method has been used in order to eliminate the above-mentioned drawbacks. That is, as shown in the voltage-current characteristic diagram of FIG. 6 (a), when the voltage of the electric power line 5 is a predetermined value, for example, Ed ₀ or more, the inverter 8 is operated at the control advance angle γ ₀ to operate the converter 3 and the inverter 8. This is a control method in which a predetermined circulating current is made to flow in the meantime, and when the train line voltage is equal to or higher than a predetermined value, the inverter 8 is controlled to a constant voltage to keep the train line voltage at a constant value, for example Vd ₁ . By controlling the inverter 8 in this way, it is possible to keep the inverter in the operating state even when the electric vehicle is in the power running mode.
The switching from the power running operation to the regenerative operation can be performed quickly and smoothly, and thereby an excessive circulating current and an abnormal voltage rise in the electric train line can be suppressed. However, according to such a control method, when the converter input voltage (commercial power supply voltage) fluctuates as shown in FIG.
_The following problem occurs depending on what voltage value the voltage (Ed ₀ ) at the start of constant control by ₀ is set. That is, the voltage at the start of the constant γ ₀ control is set to Ed ₀₁ , and the predetermined γ ₀ constant control is performed, and the train line voltage is set to A in FIG. 6 (b).
In the case of the characteristics, for example, it is assumed that the converter input voltage is at the lowest level. In this case, as is clear from the characteristic diagram of FIG. 6 (b), it becomes impossible to keep the inverter 8 in operation by supplying a predetermined circulating current when the converter 3 is in operation, and for example, switching to regenerative operation is performed. At this time, the operation of the inverter 8 is delayed and the train line voltage rises abnormally. In order to eliminate the above-mentioned drawback, the voltage at the start of constant γ ₀ control is set to Ed _02, which is lower than Ed ₀₁ , as shown in Fig. 6 (b).
It is assumed that the electric line voltage is controlled as shown by the B characteristic of. In this case, if the converter input voltage reaches the maximum level, the circulating current increases, which is uneconomical.

The present invention has been made in view of the above points, and even when the electric vehicle is in the power running operation, the inverter can be reliably operated regardless of the fluctuation of the converter input voltage, and the circulating current flowing through the inverter can be achieved. It is an object of the present invention to provide a regenerative inverter control method for electric railway and a device therefor capable of constantly suppressing the power consumption to the minimum level.

E. Means for Solving the Problems The present invention includes (1) a converter for converting the AC output power of an AC power supply into a DC power, and supplying the DC power to a train line of a DC electric railway; and an electric car for regenerative braking. In a regenerative substation equipped with an inverter that regenerates regenerative power generated at times to the power supply side,
The deviation output between the current flowing through the inverter and the predetermined circulating current setting amount is amplified by a predetermined amplification characteristic, and the deviation output between the amplification output and the predetermined regenerative voltage setting amount is matched with the train line voltage, and The inverter is phase-controlled based on the deviation output, the deviation output between the current flowing through the converter and the predetermined converter current setting amount is amplified by a predetermined amplification characteristic, and the regenerative voltage setting amount is set based on the amplification output. And (2) a converter for converting the AC output power of the AC power supply into a DC power, and supplying the DC power to the train line of a DC type electric railway, and an electric car during regenerative braking. In a regenerative substation equipped with an inverter that regenerates regenerative power to the power supply side,
A first matching unit for matching the current flowing through the inverter with a preset circulating current setting amount; a second matching unit for matching the current flowing through the converter with a preset converter current setting amount; Deviation between the third matching section and the first matching section for matching the line voltage with a preset inverter voltage setting amount, or for matching the current flowing through the inverter with a preset inverter current setting amount A first amplification section for amplifying an output with a predetermined amplification characteristic; a second amplification section for amplifying a deviation output of the second matching section with a predetermined amplification characteristic; and output signals of the first and second amplification sections. A fourth butting part for making a comparison with a preset regenerative voltage setting amount, and an electric path connecting the fourth butting part and the second amplifying part are inserted, and the third butting part is provided. Turned on based on the differential output of the allowed section,
A switching circuit controlled to be turned off, and a deviation output of the fourth matching section and the train line voltage are matched with each other.
It is characterized by including a matching section and a control section for performing phase control of the inverter based on the deviation output of the fifth matching section.

F. Action In the control device as described above, the switching circuit is off-controlled when the train line voltage is smaller than the inverter set voltage or the inverter current is smaller than the inverter set current. The output signal of the amplifier unit 1 and the regenerative voltage setting amount are matched. As a result, the inverter is subjected to constant current control to make the circulating current constant, so that an excessive circulating current does not flow even if the regenerative voltage set value and the power running voltage set value are brought close to each other. Moreover, the phase control of the inverter is performed even when the regenerative set voltage is not reached, and no operation delay occurs when the operation is switched from power running to regeneration.

Next, whether the train line voltage becomes higher than the inverter set voltage,
Alternatively, when the inverter current becomes larger than the inverter set current, the switching circuit is ON-controlled. At this time, if the inverter current is smaller than the circulating current set amount and the converter current is larger than the converter set current, the fourth
The output signals of the first and second amplifying units and the regenerative voltage setting amount are brought into contact with each other in the matching unit. Therefore, the regenerative voltage setting amount is equivalently corrected by the output of the second amplifying unit, and as a result, the control unit performs the phase control of the inverter so as to suppress the increase of the circulating current.

Next, when the electric line voltage rises due to the start of the regenerative operation of the electric vehicle and the converter current becomes smaller than the converter set current, the output of the second amplifying section becomes zero, and at this time, when the inverter current becomes larger than the circulating current set amount, the first The output of the amplification section becomes zero. Therefore, the regenerative voltage setting amount of the fourth matching section is directly corrected and matched with the electric line voltage without being corrected. The phase of the inverter is controlled based on the deviation output signal. This keeps the train line voltage constant.

G. Examples G ₁ First Example Hereinafter, one example of the present invention will be described with reference to the drawings. In FIG. 1, the same parts as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted. Transformer 2a and converter 3
A current transformer 11 is inserted in the electric path connecting the two, and a current transformer 12 is inserted in the electric path connecting the transformer 2b and the inverter 8. Current transformer 12
The AC output current is converted into DC by the AC / DC converter 13 and then introduced into the first matching circuit 14. The first matching circuit 14 matches the circulating current setting value preset by the circulating current setting device 15 with the output current of the converter 13. The amplifier 16 issues a predetermined voltage signal as shown by a characteristic curve in the range where the inverter current is smaller than the circulating current set value, and outputs a zero voltage signal when the inverter current is equal to or larger than the circulating current set value. The AC output current of the current transformer 11 is DC-converted by the AC / DC converter 17, and then introduced into the second matching circuit 18. The second matching circuit 18 matches the converter current set value preset by the converter current setting unit 19 with the output current of the converter 17. The amplifier 20 emits a predetermined voltage signal when the converter current is equal to or more than a set value as shown by a characteristic curve in the figure, and also issues a zero voltage signal when the converter current is equal to or less than the set value. The output of the amplifier 20 is introduced into a fourth matching circuit 26 described later via the analog switch 21. Reference numeral 22 is a DC / DC converter for detecting the voltage of the train line 5, and the output voltage of the converter 22 is introduced into a fifth matching circuit 28 and a third matching circuit 23 described later. The third matching circuit 23 matches the inverter voltage setting value previously set by the inverter voltage setting unit 24 and the output voltage of the converter 22. The deviation output of the third matching circuit 23 is input to the comparator 25, and the opening / closing control signal is supplied to the analog switch 21 based on the operation of the comparator 25.
The fourth matching circuit 26 matches the regenerative voltage set value previously set by the regenerative voltage setting device 27 and the output signals of the amplifier 16 and the amplifier 20. The deviation output of the matching circuit 26 is output to the DC / DC converter 22 by the fifth matching circuit 28.
Matched with the output voltage of. The output of the fifth adjusting circuit 28 is supplied to an automatic voltage adjusting circuit 31 including an amplifier 29 and a phase shifter 30. The automatic voltage adjusting circuit 31 controls the phase of the inverter 8 according to the output signal of the fifth matching circuit 28. The set voltage is set such that the set voltage (V _IN set) of the inverter voltage setting device 24 <the regenerative set voltage.

Next, the operation of the device configured as described above will be described with reference to the voltage / current characteristic diagram of FIG. First, during power running of the electric vehicle 6, it is assumed that the output voltage of the DC / DC converter 22 is lower than the set voltage of the inverter voltage setting device 24 and that no current is flowing in the inverter 8. Then the third matching circuit
Since the comparator 25 outputs the "L" level signal by the output of 23, the analog switch 21 is turned off and the output of the current transformer 12 becomes zero. Therefore, the control system does not operate, and the operation is performed only by the converter 3. As a result, the train line 5 and the voltage and current change like the B characteristic shown in region I of FIG. 3 when the converter input voltage (commercial power supply voltage) is high, and change like the A characteristic when it is low. Now A
It is assumed that the current Id flowing through the trolley wire 5 is reduced to less than Id ₁ during driving according to the characteristics. At this time, if the output current of the AC / DC converter 13 (that is, the current proportional to the current flowing through the inverter 8) is smaller than the circulating current set value of the circulating current setter 15, the amplifier 16 conforms to the illustrated amplification characteristics. It emits a predetermined voltage signal. Therefore, the fourth matching circuit 26 outputs a deviation signal obtained by matching the regenerative voltage setting value of the regenerative voltage setting device 27 and the output signal of the amplifier 16. The deviation output of the fourth matching circuit 26 is matched with the output voltage of the DC / DC converter 22 (voltage proportional to the voltage of the train line 5) in the fifth matching circuit 28. The automatic voltage adjustment circuit 31 uses the deviation output of the fifth matching circuit 28 to determine the inverter 8
Phase control. Therefore, even when the electric vehicle 6 is in the power running operation along the third A characteristic, the inverter 8 can be brought into the operating state at the time when the electric line voltage exceeds Ed _A.
As a result, constant control of the circulating current is performed.

Next, it is assumed that the voltage of the train line 5 rises and the output voltage of the DC / DC converter 22 becomes higher than the set voltage of the inverter voltage setter 24. Then, the comparator 25 outputs an "H" level signal based on the deviation output of the third matching circuit 23, so that the analog switch 21 is turned on. Here, it is assumed that the output voltage of the AC power supply 1 fluctuates and the output current of the AC / DC converter 17 (current proportional to the current flowing through the converter 3) becomes larger than the set current of the converter current setting device 19.
Then, the amplifier 20 outputs a predetermined voltage signal according to the illustrated amplification characteristic, so that the regenerative voltage setting value of the regenerative voltage setting device 27 is equivalently corrected by the output signal of the amplifier 20. Therefore, the voltage-current characteristic of FIG. 3 is switched to the B characteristic, and the operation start voltage of the inverter is raised from Ed _A to Ed _B.
This can suppress an increase in circulating current.
That is, if the operation start voltage of the inverter remains Ed _{A while} the voltage and current are changing according to the B characteristic of FIG. 3, a current Id ₂ much larger than Id ₁ is obtained.
At that time, the inverter 8 has already been operated and a large circulating current will flow. In this way, even if the output voltage of the AC power supply 1 fluctuates, the constant current control of the circulating current is performed as in the case of the A characteristic.

Next, it is assumed that the electric car 6 performs a regenerative operation and the voltage of the train line 5 further rises. At this time, if the output current of the AC / DC converter 17 (current proportional to the current flowing through the converter 3) becomes smaller than the set current of the converter current setting unit 19, the amplifier 20
Output becomes zero, and when the output current of the AC / D converter 13 (current proportional to the current flowing in the inverter 8) becomes larger than the set current of the circulating current setter 15 at this time, the output of the amplifier 16 becomes zero. . Therefore, the regenerative voltage setting device 27 and the regenerative voltage setting value are directly output from the fourth matching circuit 26 without being corrected. As a result, the automatic voltage adjusting circuit 31 controls the phase of the inverter 8 so as to keep the voltage of the train line 5 constant, so that the regenerative electric power generated by the electric vehicle 6 is smoothly regenerated.

G ₂ Second Embodiment Next, another embodiment of the present invention will be described with reference to FIG. In FIG. 2, the same parts as those in FIG. 1 are indicated by the same reference numerals, and the description thereof will be omitted. 2 is different from FIG. 1 in that an inverter current setting device 34 is provided in place of the inverter voltage setting device 24, and the current preset by the setting device 34 and the output current of the AC / DC converter 13 (inverter 8) and a current proportional to the current flowing in 8) are matched in the third matching circuit 23.

The setting current is the setting current (Ijse
t) <Set current of inverter current setting device 34 (I _IN set) <
Set the relation to the set current (I _CN set) of the converter current setter 19.

Next, the operation of the device configured as described above will be described with reference to the voltage / current characteristic diagram of FIG. First, during the power running operation of the electric vehicle 6, no current is flowing through the inverter 8 and the AC / D
It is assumed that the output current of the C converter 13 is smaller than the set current of the inverter current setting device 34. Then, the comparator 25 outputs an "L" level signal by the output of the third matching circuit 23, so that the analog switch 21 is turned off. Therefore, the control system does not work, and the operation is performed only by the converter 3. As a result, the voltage and current of the train line 5 change like the B characteristic shown in the region I of FIG. 3 when the converter input voltage (commercial power supply voltage) is high, and change like the A characteristic when it is low. Now, it is assumed that the current Id flowing through the electric train line 5 decreases and becomes Id ₁ or less along the characteristic A while driving. AC / DC at this time
If the output current of the converter 13 (that is, the current proportional to the current flowing through the inverter 8) is smaller than the circulating current setting value of the circulating current setting device 15, the amplifier 16 issues a predetermined voltage signal according to the illustrated amplification characteristic. . For this reason the 4th matching circuit
Reference numeral 26 outputs a deviation signal obtained by matching the regenerative voltage setting value of the regenerative voltage setting device 27 and the output signal of the amplifier 16.
The deviation output of the fourth matching circuit 26 is matched with the output voltage of the DC / DC converter 22 (voltage proportional to the voltage of the train line 5) in the fifth matching circuit 28. The automatic voltage adjusting circuit 31 controls the phase of the inverter 8 based on the deviation output of the fifth matching circuit 28. Therefore, even when the electric vehicle 6 is in the power running operation according to the characteristic A in FIG. 3, the inverter 8 can be brought into an operating state even when the trolley line voltage exceeds Ed _A. As a result, constant control of the circulating current is performed.

Next, the output current of the AC / DC converter 13 changes to the inverter current setting device 3
It is assumed that the current exceeds the set current of 4. Then, the comparator 25 outputs an "H" level signal based on the deviation output of the third matching circuit 23, and the analog switch 21
Is controlled on. Here, it is assumed that the output voltage of the AC power supply 1 fluctuates and the output current of the AC / DC converter 17 (current proportional to the current flowing through the converter 3) becomes larger than the set current of the converter current setting device 19. Then, the amplifier 20 outputs a predetermined voltage signal according to the illustrated amplification characteristic, so that the regenerative voltage setting value of the regenerative voltage setting device 27 is equivalently corrected by the output signal of the amplifier 20. Therefore, the voltage-current characteristic of FIG. 3 is switched to the B characteristic, and the operation start voltage of the inverter is
Raised from Ed _A to Ed _B. This can suppress an increase in circulating current. That is, if the operation start voltage of the inverter is still Ed _A when the voltage and the current are changing according to the characteristic B of FIG. 3, Id ₁
At a time when the current Id ₂ becomes much larger than the current Id ₂ , the inverter 8 already operates and a large circulating current flows.
In this way, even if the output voltage of the AC power supply 1 fluctuates, the constant current control of the circulating current is performed as in the case of the A characteristic.

Next, it is assumed that the electric car 6 performs a regenerative operation and the voltage of the electric train line 5 rises. At this time, when the output current of the AC / DC converter 17 (current proportional to the current flowing in the converter 3) becomes smaller than the set current of the converter current setting device 19, the output of the amplifier 20 becomes zero, and at this time, the AC / DC conversion When the output current of the device 13 (current proportional to the current flowing through the inverter 8) becomes larger than the set current of the circulating power setting device 15, the output of the amplifier 16 becomes zero. Therefore, the regenerative voltage setting value of the regenerative voltage setting device 27 is directly output from the fourth matching circuit 26 without being corrected. As a result, the automatic voltage adjustment circuit 31 becomes
Since the phase control of the inverter 8 is performed so as to keep the voltage of 1 constant, the regenerative electric power generated by the electric vehicle 6 is smoothly regenerated.

H. Effects of the Invention As described above, according to the present invention, the following effects can be obtained. That is, (1) Even if the electric vehicle is in the power running mode and the commercial power supply voltage fluctuates, constant current control is performed to keep the circulating current constant, so that an excessive circulating current does not flow. Further, since the circulating current is small, energy saving can be achieved.

(2) Since the inverter operates even during the power running operation of the electric vehicle, it is possible to smoothly shift to the regenerative operation without causing an operation delay during the regenerative operation of the electric vehicle.

(3) Due to the reason of the above item (2), it is possible to suppress the abnormal voltage rise of the electric power line, and thus the safety of the electric vehicle is maintained.

(4) Since the electric vehicle can smoothly perform regenerative braking during regenerative operation, it is not necessary to use an air brake, and smooth operation can be continued.

(5) Since the electric power generated by the electric vehicle during regenerative operation can be quickly regenerated to the AC power source side, the regenerated electric power can be effectively used.

(6) The transition from regenerative operation to power running can be performed smoothly.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a circuit diagram showing another embodiment of the present invention, and FIG. 3 is a voltage-current characteristic diagram for explaining a control pattern of the present invention. FIG. 4 is a circuit diagram showing an example of a conventional regenerative substation system, and FIGS. 5 and 6 (a), (b) are voltage-current characteristic diagrams for explaining a conventional control pattern. . 1 ... AC power supply, 3 ... Converter, 5 ... Train line, 6
...... Electric car, 8 …… Inverter, 11,12 …… Current transformer, 14
...... First matching circuit, 15 ...... Circulating current setting device, 16,2
0 ... Amplifier, 18 ... Second matching circuit, 19 ... Converter current setting device, 21 ... Analog switch, 23 ... Third matching circuit, 24 ... Inverter voltage setting device, 25 ...
… Comparator, 26 …… 4th matching circuit, 27 …… Regenerative voltage setting device, 28 …… Fifth matching circuit, 31 …… Automatic voltage adjusting circuit, 34 …… Inverter current setting device.

Claims (2)

[Claims] 1. A converter for converting the AC output power of an AC power supply into a DC power, and supplying the DC power to the trolley line of a DC electric railway, and an inverter for regenerating the regenerative power generated by an electric car during regenerative braking to the power supply side. In a regenerative substation equipped with, a deviation output between the current flowing through the inverter and a predetermined circulating current set amount is amplified by a predetermined amplification characteristic, and a deviation output between the amplified output and a predetermined regenerative voltage set amount is output. Amplify the deviation output between the current flowing through the converter and a predetermined converter current setting amount by a predetermined amplification characteristic by matching with the train line voltage and controlling the phase of the inverter based on the deviation output. A control method for a regenerative inverter for electric railway, wherein the set amount of regenerative voltage is corrected based on an output. 2. A converter for converting the AC output power of the AC power supply to DC and supplying the DC power to the trolley line of a DC electric railway, and an inverter for regenerating the regenerative power generated by an electric car during regenerative braking to the power supply side. In a regenerative substation equipped with, a first matching section for matching the current flowing through the inverter with a preset circulating current setting amount and the current flowing through the converter with the preset converter current setting amount A second matching section and a third matching section for matching the voltage of the electric power line with a preset inverter voltage setting amount, or for matching the current flowing through the inverter with a preset inverter current setting amount; , A first amplifier for amplifying the deviation output of the first matching section with a predetermined amplification characteristic, and a deviation output of the second matching section for a predetermined value. A second amplifier for amplifying a width characteristic,
A fourth matching section for matching the output signals of the first and second amplifying sections with a preset regenerative voltage setting amount, and an electric path connecting the fourth matching section and the second amplifying section, A switching circuit that is on / off controlled based on the deviation output of the third matching section, a fifth matching section that matches the deviation output of the fourth matching section with the train line voltage, and a fifth matching section. A control unit for a regenerative inverter for electric railway, comprising: a control unit that controls the phase of the inverter based on the deviation output of the butting unit.