JP2010252617A - Charging control method in feeder voltage compensator for electric railways - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a feeder failure due to overvoltage and charge an electric double-layer capacitor up to the maximum possible level. <P>SOLUTION: In the method of charge control, a current command value obtained by inputting a current command value output from a PI amplifier 23 to a limiter 24 to be controlled is compared with a new current command value refined by a filter 34 for refining a current command value in consideration of internal resistance of an electric double-layer capacitor using a comparator 32, and outputs a smaller current command value as a charging current command value. A deviation output between the charging current command value output from the comparator 32 and a detected value of the charging current value of the electric double-layer capacitor is obtained. The output is input to an amplifier 28 for controlling a duty ratio through a PI amplifier 26 after obtaining a PI control output for determining a duty of a bidirectional chopper means. A PWM signal corresponding to the duty ratio is created in a CMP creation part 29 from the amplifier 28. From the PWM signal and a condition signal when regenerative electric power is generated, a gate signal is obtained. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a feeder voltage compensation device in an electric railway, and more particularly to a method for controlling charging of an electric double layer capacitor used in a power storage device of a feeder voltage compensation device.

  In electric railways, feeder voltage compensators are provided to suppress the occurrence of voltage drop and voltage rise during power running and regeneration of electric vehicles. This feeder voltage compensation device is composed of a power conversion device and a power storage device, and an electric double layer capacitor (EDLC) is used for the power storage device, and this electric double layer capacitor uses the regenerative power of the electric vehicle as power. The converter is configured to be charged with constant feed voltage control.

  In the power converter, when the EDLC is close to full charge, the first method and the second method using only the EDLC shown in FIG. 10 described later, and the EDLC and resistance shown in FIG. 11 described later are used. There is a third system that absorbs regenerative power in combination.

  The first method and the second method are control methods for stopping the regenerative power when fully charged, and the third method is a control method for absorbing the regenerative power (see Patent Document 1).

  FIG. 10 is a schematic configuration diagram showing the first method. In FIG. 10, reference numeral 1 is a feeder line, 2 is a rail, and a power converter 60 is provided between the feeder line 1 and the rail 2. The converter 60 includes a switching component removal filter 5 including a reactor 3 and a capacitor 4, and a bidirectional chopper means 6 provided between a common connection point of the reactor 3 and the capacitor 4 and the rail 2. Between the common connection point of the two upper and lower semiconductor switching elements 6 a and 6 b and the rail 2, an EDLC 8, which is a power storage device 61, is provided via the smoothing reactor 7.

  In addition, 10 is a feeding current detection unit, 11 is a feeding voltage detection unit, 12 is an EDLC current detection unit, and 13 is an EDLC voltage detection unit.

  As the regenerative power absorption control conventionally used, the control operation of the first method of the schematic configuration diagram shown in FIG. 10 will be described using the control block configuration diagram of FIG.

  In FIG. 12, the deviation between the feeding voltage detection value and the feeding reference voltage value is obtained by the deviation unit 21, and the deviation output of the deviation unit 21 is input to the standardization computation unit 22. The standard input value is divided by the rated value to obtain a standard calculation output value (for example, when the rated voltage is 2000 V and the input voltage is 1000 V, the standard calculation output value is 0.5). This output value is input to the PI amplifier 23 to obtain a current command value as an output. The current command value is input to the limiter 24 and subjected to a limit process of “0 to 1”, and then the deviation between the current command value subjected to the limit process and the charge current detection value of the EDLC is obtained by the deviation unit 25. The deviation output is supplied to the PI amplifier 26, and the PI amplifier 26 sends out a PI control output that determines the duty of the bidirectional chopper means 6.

  The PI control output sent from the PI amplifier 26 is limited to “0 to 1” by the limiter 27 and is inputted to the DUTY amplifier 28 that controls the duty ratio of the bidirectional chopper means 6. The CMP generator 29 generates a PWM signal corresponding to the duty ratio output from the DUTY amplifier 28.

  An AND circuit unit 30 is supplied with a charge permission condition signal and a gate permission condition signal (charge / discharge permission mode) sent from a system (not shown) when regenerative power is generated. When the charge permission condition signal and the gate permission condition signal are satisfied, an output signal is supplied from the AND circuit section 30 to the first input terminal of the AND circuit section 31. The PWM signal generated by the CMP generation unit 29 is supplied to the second input terminal of the AND circuit unit 31. When signals are supplied to both of these input terminals, a gate signal for controlling the bi-directional chopper means 6 is sent from the output of the AND circuit unit 31, and the bi-directional chopper means 6 is controlled by the gate signal to the EDLC 8. The charging current is controlled.

  In the regenerative power absorption control in which the control operation of the first method is performed as described above, charging is performed only by the voltage condition of EDLC.

  Therefore, the second type regenerative power absorption control shown in the control block configuration diagram of FIG. 13 has been devised. The control block configuration diagram shown in FIG. 13 is improved so that regenerative power absorption control is performed by limiting the charging current in consideration of the EDLC voltage, and the configuration and operation different from those in FIG. 12 will be described below.

  In FIG. 13, a comparator 32 is inserted in the electric path between the limiter 24 and the deviation unit 25, and the output of the filter 33 that narrows down the current command value is supplied depending on the comparator 32 and the EDLC voltage shown in FIG. The comparator 32 compares the current command value from the PI control supplied via the limiter 24 with the current command value (filter output α) narrowed down by the filter 33, and the comparator 32 has a smaller value. One current command value is output.

  The deviation unit 25 obtains a deviation between the current command value output from the comparator 32 and the charge current detection value of the EDLC. The obtained deviation output is supplied to the PI amplifier 26 to obtain a PI control output as an output. The obtained PI control output determines the duty of the bidirectional chopper means 6, and is input to the DUTY amplifier 28 for controlling the duty ratio of the bidirectional chopper means 6 via the limiter 27, and the subsequent processing is shown in FIG. Done as described.

  FIG. 11 is a schematic configuration diagram showing the third system. The same parts as those in FIG. In this third system, a first series body 15 of the EDLC 8 and the switch 14 and a second series body 18 of a resistor 16 and a switch 17 are connected in parallel to the first series body 15 so that both series bodies 15 are connected. , 18 is formed between the common connection point of the upper and lower semiconductor switching elements 6a, 6b of the bidirectional chopper means 6 and the rail 2 via the smoothing reactor 7.

  In this third method, after the switches 14 and 17 are closed and the EDLC 8 and the resistor 16 are connected in parallel, the voltage of the EDLC 8 further increases, and the feeder voltage becomes higher than the threshold value due to the regenerative power of the electric vehicle. Only the EDLC 8 is disconnected, and the regenerative power is absorbed by the resistor 16.

  In addition to the above, in order to maximize the power storage (storage) capability of the EDLC, charging is performed by constant current control, and charging by the constant voltage control (relaxation charging) after the EDLC reaches the full charge voltage V1. There is a method of performing (see Patent Document 2).

JP 2001-206110 A Japanese Patent No. 4022362

Next, the problem at the time of regenerative power absorption from an electric vehicle is described.
(1) First, the problem of no charging current restriction (problem of the first method)
When charging is performed only under voltage conditions, if the regenerative power absorption operation is suddenly stopped when the EDLC voltage exceeds the fully charged voltage, the following problem occurs.

When the feeding voltage rises, the electric vehicle side throttles the regenerative current and brakes with the mechanical brake. If the feeding voltage rises suddenly, the regenerative current cannot be narrowed in time, and the feeding voltage is rising However, since regenerative power is generated from the electric vehicle, the feeding voltage may be overvoltage.
(2) Problems due to EDLC internal resistance (problems of the first and third methods)
Since the EDLC has an internal resistance, when charging is stopped, the EDLC voltage may be lower than that immediately before the charging is stopped due to the voltage drop caused by the internal resistance and the charging current.

  FIG. 15 is an equivalent circuit diagram of the EDLC. In FIG. 15, R represents an internal resistance, I represents a charging current, and RI represents a voltage drop.

  FIG. 16 is a characteristic diagram showing how the EDLC voltage drops when the EDLC has an internal resistance, and when the EDLC stops charging during charging, the voltage drops due to the internal resistance and the charging current.

  In FIG. 16, the rising solid line is the EDLC voltage V11, the broken line is the voltage V12 obtained by subtracting the voltage drop due to the internal resistance of the EDLC from the EDLC voltage, and the EDLC voltage V11 is stopped when charging to the EDLC is stopped at time t1. Since the charging current I is not supplied to the voltage V11, the voltage V11 is reduced to the voltage V13 by the voltage drop at the internal resistance R.

For this reason, the voltage drop after stopping charging increases as the charging current I increases or the internal resistance R increases. As a result, it becomes an uneconomic charging method to use an EDLC that can be charged up to a voltage difference from full charge as a power storage device.
(3) Problems with the EDLC voltage filter (shown in FIG. 14) (problems of the second method)
When a filter that narrows the current command value depending on the EDLC voltage is used, the charge current to the EDLC is narrowed before the EDLC voltage reaches the charge voltage upper limit “Vedlc”, that is, while there is room in the chargeable capacity. Therefore, when the regenerative current from the electric vehicle is large, there is a problem that the EDLC cannot be sufficiently charged. Further, when the internal resistance of the EDLC increases due to secular change or the like, the original current command value (filter output αn) vibrates (the reason for this vibration will be described later) as shown in FIG. 17 due to a voltage drop due to the current command value. As a result of starting, vibration vib as shown in FIG. 18 as a simulation result may occur, and the feeding voltage may become unstable.

  Next, the reason why the above-described vibration is generated will be described. The EDLC has an internal resistance R as shown in FIG. 15, and the internal resistance R increases with aging. When the EDLC is charged by the internal resistance R, the EDLC voltage [measured value] is higher than the case where there is no charging current as shown in the following equation.

Vedlc [measured value] = internal resistance R × charge current + Vedlc [no current]
Therefore, when the internal resistance R of the EDLC increases, the voltage drop due to the internal resistance also increases.

  Next, FIG. 17 shows a filter characteristic diagram when the internal resistance value of the EDLC becomes larger than the initial setting. The filter characteristic diagram shown in FIG. 17 assumes a case where the internal resistance value is twice the initial setting for easy understanding. In FIG. A "desirable" filter corresponding to a large internal resistance value (a filter that should be corrected when the internal resistance value doubles), and the steep line segment S is the default filter (the initial internal resistance value) Filter).

  Here, consider a case where the EDLC is in a charged state and has a voltage value Vedlc (n). At this time, the voltage value Vedlc (n) is expressed by the following equation.

Vedlc (n) [measured value] = internal resistance × charge current (n) + Vedlc (n) [no current]
From FIG. 17, the filter output is αn + 1, and αn corresponding to the current internal resistance is originally a desirable value. At this time, αn <αn + 1, and the current command value becomes larger than a desired value as shown in the following equation.

Vedlc (n + 1) [measured value] = internal resistance × charge current (n + 1) + Vedlc (n + 1) [no current]
Then, Vedlc (n + 1) becomes a higher voltage than Vedlc ′ (n) due to the voltage drop due to the internal resistance × current, and this time, it starts from this higher Vedlc (n + 1). Vedlc (n + 1) is the EDLC voltage by the filter before correction (voltage drop due to EDLC internal resistance), and Vedlc 'is the EDLC voltage by the filter after correction (voltage drop by EDLC internal resistance).

  The current command value at Vedlc (n + 1) becomes αn + 2, this time the current command value becomes smaller than the desired value, and the voltage value Vedlc (n + 2) (not shown in FIG. 17) is expressed by the following equation.

Vedlc (n + 2) [measured value] = internal resistance × charge current (n + 2) + Vedlc (n + 2) [no current]
At this time, the EDLC voltage is lower than a desired value. A current command value αn + 3 (not shown) based on the low voltage value Vedlc (n + 2) is a command to flow a current larger than the current command value by the corrected filter. In this way, the current command value of the filter repeatedly becomes unstable from a desired value to a larger value, a smaller value, a larger value, a smaller value, a larger value, a smaller value, and so on.

As described above, the current command value of the filter repeatedly increases and decreases, and the EDLC voltage vibrates.
(4) Problems of combined use of EDLC and resistors (Problems of the third method)
In this case, there is no problem in terms of feeding voltage stability, but when the resistor and the EDLC are charged in parallel, if the regenerative current is small, the EDLC is discharged to the parallel resistor, and electric energy is wasted. There is a problem.

Further, the EDLC voltage immediately after the EDLC disconnection has a problem that it is difficult to be charged up to the charging voltage upper limit due to a voltage drop corresponding to the internal resistance. The condition for completing the charge with the highest EDLC voltage is only EDLC disconnection when Vedlc = Vr≈Vedlc (charge voltage upper limit) and Iedlc≈0 when EDLC is connected in parallel with the resistor. Considering that the resistance is fixed, it is almost impossible to realize.
(5) Problems in the method of switching from constant current charging to constant voltage discharging (problems of Patent Document 2)
Since this charging method is not control that actively absorbs regenerative power of an electric vehicle, it does not perform control according to constant feeding voltage control but does not perform absorption according to regenerative power. Therefore, there is a problem that it is not possible to cope with a change in feeding voltage.

  The object of the present invention is made in view of the above circumstances, and even if the voltage of the EDLC reaches the upper limit of the charging voltage, the regenerative power is used to gradually reduce the charging current without suddenly stopping the charging. While mitigating the feeding voltage rise, it is possible to provide a margin for the regenerative throttle operation on the electric vehicle side, and it is possible to prevent the occurrence of feeder overvoltage failure, and limit the EDLC to the upper limit of the charging voltage. It is an object of the present invention to provide a charging control method in a feeder voltage compensation device for electric railway that can be charged up to near.

In order to achieve the above-mentioned object, the invention according to claim 1 is directed to wire voltage compensation for stabilizing the feeding voltage by suppressing fluctuations in the feeding voltage generated during regeneration and power running of the electric vehicle in the electric railway. The feeder voltage compensation device is composed of a power conversion device and a power storage device, the power conversion device is provided with a bidirectional chopper means, the power storage device is provided with an electric double layer capacitor, In the charge control method of charging the electric double layer capacitor with regenerative power from an electric vehicle by controlling the bidirectional chopper means,
After obtaining the first deviation from the feed voltage detection value and the power reference voltage value, PI control is performed on the output of the first deviation to obtain a first current command value,
The charging current detection value and the charging voltage detection value of the electric double layer capacitor and the charging voltage upper limit value of the known electric double layer capacitor and the internal resistance value of the charging current detection value and the maximum charging current value at that time that is less than the charging voltage upper limit value A filter in which the maximum charging current value is equal to or higher than the charging current upper limit value of the electric double layer capacitor, and the charging current upper limit value is set as the second current command value in the following cases. Send out using
After comparing the first current command value and the second current command value obtained through the filter, the smaller one of the first and second current command values was obtained as the charge current command value. rear,
PI control is performed on the output of the second deviation between the charge current command value and the charge current detection value of the electric double layer capacitor, and a gate signal of the bidirectional chopper means is generated based on the PI control output. The bidirectional chopper means is controlled by a gate signal to absorb the regenerative power of the electric vehicle.

  The invention according to claim 2 is characterized in that, in claim 1, the maximum charging current value is obtained by the following equation.

According to a third aspect of the present invention, there is provided a wire voltage compensation device for suppressing the fluctuation of the feeding voltage generated during the regeneration and power running of the electric vehicle in the electric railway, thereby stabilizing the feeding voltage. The apparatus is composed of a power conversion device and a power storage device, the power conversion device is provided with a bidirectional chopper means, the power storage device is provided with an electric double layer capacitor, and under the control of the bidirectional chopper means, In the charge control method for charging the electric double layer capacitor with regenerative power from an electric vehicle,
After obtaining the first deviation from the feed voltage detection value and the power reference voltage value, PI control is performed on the output of the first deviation to obtain a first current command value,
A second deviation between the charge voltage detection value of the electric double layer capacitor and its reference voltage value is obtained. When the charge voltage detection value of the electric double layer capacitor exceeds the current throttling start voltage value, an output of the second deviation is obtained. Obtaining a current aperture value based on the electric double layer capacitor voltage obtained by PI control, and obtaining a third deviation between the current aperture value and the first current command value as a second current command value,
After comparing the first current command value and the second current command value, after obtaining the smaller one of the first and second current command values as the charging current command value,
PI control is performed on the output of the fourth deviation between the charge current command value and the charge current detection value of the electric double layer capacitor, and the gate signal of the bidirectional chopper means is generated based on the PI control output. The bidirectional chopper means is controlled by a gate signal to absorb the regenerative power of the electric vehicle.

  The invention according to claim 4 is characterized in that, in claim 3, the second current command value controls a current aperture value so that the electric double layer capacitor does not become overvoltage.

According to a fifth aspect of the present invention, there is provided a wire voltage compensation device that suppresses fluctuations in the feeding voltage that occurs during regeneration and power running of an electric vehicle in an electric railway, thereby stabilizing the feeding voltage. The apparatus is composed of a power conversion device and a power storage device, the power conversion device is provided with a bidirectional chopper means, the power storage device is provided with an electric double layer capacitor, and under the control of the bidirectional chopper means, In the charge control method for charging the electric double layer capacitor with regenerative power from an electric vehicle,
The constant current command value of the constant current command unit is obtained as the first current command value,
The first deviation between the charge voltage detection value of the electric double layer capacitor and the reference voltage value is obtained, and when the charge voltage detection value of the electric double layer capacitor exceeds the current throttling start voltage value, the output of the first deviation is PI controlled. A value obtained by obtaining a second deviation between the current aperture value obtained by the electric double layer capacitor voltage and the first current command value is defined as a second current command value.
After comparing the first current command value and the second current command value, after obtaining the smaller command value of both command values as the charging current command value,
PI control is performed on the output of the third deviation between the charging current command value and the charging current detection value of the electric double layer capacitor, and a gate signal of the bidirectional chopper means is generated based on the PI control output. The bidirectional chopper means is controlled by a gate signal to absorb the regenerative power of the electric vehicle.

  According to the present invention, even if the EDLC voltage reaches the charging voltage upper limit value, the charging current is gradually reduced without suddenly stopping charging by the control of the power conversion device, so that the feeding voltage rise due to regenerative power is alleviated. In addition, it is possible to afford a regenerative throttle operation on the electric vehicle side, and to prevent occurrence of feeder overvoltage failure.

  In addition, according to the present invention, it is possible to charge as close as possible to the upper limit value of the charging voltage by the same control as described above, and more electric energy can be charged, and power consumed wastefully in resistors and the like. There is an advantage that there is no.

  Furthermore, according to the present invention, since the charging current restrictor to the EDLC can be operated after the EDLC voltage becomes high, the electric energy can be charged without waste.

  Furthermore, according to the present invention, even when the internal resistance value changes due to aging of the EDLC, it is possible to charge the EDLC up to the charging voltage upper limit value without changing the charging current restrictor according to the change of the internal resistance value. And the like.

  In addition to the above, according to the present invention, when the EDLC is almost fully charged, when charging is terminated so that the EDLC does not become an overvoltage, the charging current is calculated by using only the EDLC voltage for the calculation for reducing the charging current. By performing the control to decrease, there is an advantage that the calculation element, the number of calculations, and the amount of used memory can be reduced.

FIG. 1 is a block diagram of a regenerative power absorption control block adopting a charging current restrictor used in the first embodiment of the present invention. FIG. 2 is a filter characteristic diagram in consideration of a voltage drop due to the EDLC internal resistance used in the first embodiment. FIG. 3 is a diagram illustrating the filter characteristics of FIG. 2 using specific numerical values. FIG. 4 is an explanatory diagram of a simulation result illustrating an operation example of the filter used in the first embodiment. FIG. 5 is a block diagram of a regenerative power absorption control block with constant feeding voltage control that performs charging current throttling only with the EDLC voltage used in Embodiment 2 of the present invention. FIG. 6 is a block diagram of a regenerative power absorption control block in constant current control that performs charging current throttling only with the EDLC voltage used in the third embodiment of the present invention. FIG. 7 is an explanatory diagram for describing current restriction only by the EDLC voltage. FIG. 8 is an explanatory diagram showing an Iedlc (EDLC charging current value) -Vedlc (EDLC voltage value) locus in the simulation feeding voltage constant control. FIG. 9 is an explanatory diagram of an example of the operation in the conventional second method, in which the regenerative aperture operates in the case of the same regenerative power as in FIG. FIG. 10 is a schematic configuration diagram for charging regenerative power using only EDLC. FIG. 11 is a schematic configuration diagram for charging regenerative power using an EDLC and a resistor. FIG. 12 is a block diagram of a conventional regenerative power absorption control block. FIG. 13 is a block diagram of a regenerative power absorption control block employing a charging current restrictor using a conventional EDLC voltage filter. FIG. 14 is a filter characteristic diagram according to a conventional EDLC voltage. FIG. 15 is an equivalent circuit diagram of the EDLC. FIG. 16 is a diagram for explaining a decrease in the EDLC voltage due to the stop of the charging current. FIG. 17 is an explanatory diagram showing an operation example when the internal resistance value in the conventional EDLC voltage filter becomes larger than the setting. FIG. 18 is an explanatory diagram of a simulation result in which vibration is generated in a conventional EDLC voltage filter. FIG. 19 is an explanatory diagram of a simulation result illustrating an operation example when the filter of the first embodiment is used. FIG. 20 is an explanatory diagram of a simulation result when the internal resistance of the EDLC is doubled as designed in FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a control block diagram of regenerative power absorption control employing the charging current restrictor used in Embodiment 1 of the present invention. The same parts as those in FIGS. Omitted.

  In FIG. 1, a deviation from the power reference voltage value when the feed voltage detection value (hereinafter referred to as feed voltage) detected by the feed voltage detector 11 shown in FIG. 10 is obtained by the deviation unit 21, and the deviation output of the deviation unit 21 is obtained. The value input to the standardization calculation unit 22 is divided by the rated value by dividing the value input by the standard calculation unit 22 (for example, when the rated voltage is 2000V and the input voltage is 1000V, as the standard calculation output value) 0.5). This output value is input to the PI amplifier 23 to obtain a current command value as an output. This current command value is input to the limiter 24 and subjected to a restriction process of “0 to 1”.

  The comparator 32 compares the current command value limited by the limiter 24 with the new current command value narrowed by the filter 34 that narrows the current command value in consideration of the internal resistance value of the EDLC shown in FIG. The smaller current command value is output as the charging current command value.

  A deviation between the charge current command value output from the comparator 32 and the charge current detection value of the EDLC (detected by the EDLC current detector 12 shown in FIGS. 10 and 11) is obtained by the deviation unit 25. The PI amplifier 26 supplies a PI control output that determines the duty of the bidirectional chopper means 6.

  The PI control output sent from the PI amplifier 26 is limited to “0 to 1” by the limiter 27 and is inputted to the DUTY amplifier 28 that controls the duty ratio of the bidirectional chopper means 6. The CMP generator 29 generates a PWM signal corresponding to the duty ratio output from the DUTY amplifier 28.

  An AND circuit unit 30 is supplied with a charge permission condition signal and a gate permission condition signal (charge / discharge permission mode) sent from a system (not shown) when regenerative power is generated. When the charge permission condition signal and the gate permission condition signal are satisfied, an output signal is supplied from the AND circuit section 30 to the first input terminal of the AND circuit section 31. Further, the PWM signal generated by the CMP generating unit 29 is supplied to the second input terminal of the AND circuit unit 31. When signals are supplied to both of these input terminals, a gate signal is given from the output of the AND circuit unit 31 to the bidirectional chopper means 6 shown in FIGS. 10 and 11, and the semiconductor switching 6a of the bidirectional chopper means 6 is performed. , 6b are controlled.

FIG. 2 is a filter characteristic diagram of the filter 34 that narrows down the current command value in consideration of the voltage drop due to the internal resistance of the EDLC used in the first embodiment, and this filter 34 is the EDLC current detector 12 (FIG. 10). EDLC charging current value i _EDLC (measurement) measured in FIG. 11), EDLC voltage value V _EDLC (measurement) measured in the EDLC voltage detector 13 (shown in FIGS. 10 and 11), and known EDLC maximum charge voltage value V _EDLC (charge upper limit) and EDLC internal resistance value R _EDLC (internal) are used to obtain the maximum charge current value i _filter at that time from the following equation.

Note that the maximum charging current value i _filter is limited so that the charging current to the EDLC is less than or equal to the maximum current.

  Further, in the filter characteristics shown in FIG. 2, the shaded portion is the range where the current command value is restricted.

  Next, the operation of the filter characteristics of FIG. 2 will be described using specific numerical values shown in FIG.

In FIG. 3, in the case of EDLC voltage (hereinafter Vedlc) [measurement value] = 850 V, EDLC current = 1800 A,
Vedlc [no current] = Vedlc [measurement] −0.1Ω × 1800A = 670V
If the internal resistance value of the EDLC is 0.1Ω at this time, it can be estimated that the EDLC voltage does not exceed 1000V even when charged to (1000V−670V) /0.1Ω=3300A.

  The filter output α is obtained by standardizing this value with the EDLC reference value 2000A.

α = {1800+ (1000−850) /0.1} / 2000 = {1800 + 1500} /3300=1.65
Α obtained as described above is “1.65”, but since the maximum value of α is “1”, α = 1.

Next, in the case of Vedlc [measured value] = 1020 V and EDLC current 800 A, Vedlc [no current] = 940 V, internal resistance 0.1 × EDLC current = 80 V
At this time, α = {800+ (1000−1020) /0.1} /2000=600/2000=0.3
From the above, the upper limit of the EDLC current is 600 A, and α is “0.3”.

Further, when Vedlc [measured value] = 950 V and EDLC current = 400 A, Vedlc [no current] = 910 V, internal resistance 0.1 × EDLC current = 40 V
At this time, α = {400+ (1000−950) /0.1} /2000=900/2000=0.45
From the above, the upper limit of the EDLC current is 900 A, and α is “0.45”.

  Using the filter output α characteristic as described above, the current Vedlc [no current] is estimated from the current EDLC voltage and the EDLC current, and the upper limit of the charging current is obtained. The filter output α is obtained from the following equation.

  Where Iedlc: measured EDLC charging current value, Vedlc [measured value]: measured EDLC voltage value, Vedlc charging upper limit value: EDLC maximum charging voltage value, Redlc: EDLC internal resistance value, Iedlc max: EDLC maximum charging current Value.

  The charge control method in the first embodiment is performed without changing the chopper control even when the battery is close to full charge. In other words, the operation is to reduce the regenerative power by estimating the EDLC voltage value [no current] as the upper limit of the current command value. When Vedlc [measured value] is “far” to full charge, the upper limit is 1 and the above calculation is performed. Even if the value obtained by the equation is working and Vedlc [measured value] is close to full charge, a gate signal is sent so as not to perform a rapid stop control of the chopper.

In addition, in Example 1 of this invention, the following effects are obtained.
(A) Since the charging current is gradually decreased without suddenly stopping charging even when the EDLC voltage value is close to the charging voltage upper limit value, an increase in feeding voltage due to regenerative power can be mitigated. It is possible to prevent the electric wire from being overvoltage.
(B) Since the EDLC voltage value can be charged as close as possible to the charge voltage upper limit value, the energy efficiency is increased.
(C) As shown in FIG. 19, since the EDLC charging current restrictor is operated after the EDLC voltage value is increased, the energy efficiency is improved as described above.

  As an operation example of the simulation result using the filter in the first embodiment of the present invention, as shown in FIG. 20, even if the internal resistance value of the EDLC increases twice as much as the design time, no correction of the diaphragm filter is necessary. In addition, the operation of the charging throttle is also after a few seconds (6 to 7 seconds in the operation example) has elapsed since the start of charging, and the operation of absorbing regenerative power can be performed longer than when a conventional EDLC voltage filter is used. .

  Further, FIG. 4 is an operation example of a charge simulation result using a filter that takes into account the voltage drop of the first embodiment. The charge simulation conditions include the charge voltage upper limit value of the EDLC voltage: 1250 V, the EDLC overvoltage value: 1400 V, Feeding line no-load voltage value: 1650V, feeder overvoltage value: 1900V, EDLC maximum current 2000A, simulation time equivalent to 15 seconds (150,000 samples), regenerative current becomes 1000A at 1.5 seconds after starting regeneration, and lasts for 5 seconds The one that becomes “0” A over the next 6 seconds is used.

An example of the operation under the above conditions is a case where regenerative power is applied to EDLC and absorbed only by the feeder voltage compensation device (the regenerative aperture is not activated). On the other hand, FIG. 9 shows an example of operation in the conventional second method. In the case of the same regenerative power as in FIG. 4, an example in which the regenerative diaphragm operates is shown. It is 80% of the charging voltage upper limit value Vedlc.
(D) Even if the internal resistance of the EDLC increases due to secular change or the like, it is possible to operate without changing the charging current restrictor.

  As a result, even if the internal resistance of the EDLC increases twice, stable operation can be performed as shown in FIG.

  FIG. 5 is a block diagram of a regenerative power absorption control block with constant feed voltage control showing Embodiment 2 of the present invention. When the EDLC approaches full charge in this feed voltage constant control, FIG. In this method, the charging current is reduced only by the voltage Vedlc. In FIG. 5, the same parts as those in FIGS. 1, 12, and 13 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 5, a feeding voltage constant control unit 20 surrounded by a broken line in the figure includes a deviation unit 21 for obtaining a deviation from the feeding reference voltage value when the feeding voltage detection value, and a standard calculation output value by dividing the deviation output by the rated value. The normalization calculation unit 22 for obtaining the current command value, the PI amplifier 23 for obtaining the current command value from the output value, and the limiter 24 for limiting the current command value. Then, a current command value from the feeding voltage constant control unit 20 is sent to the output of the limiter 24. The output value of the feeding voltage constant control unit 20 is defined as a first current command value A.

  In the figure, reference numeral 50 denotes a current restricting unit using an EDLC voltage. This current restricting unit 50 determines whether the EDLC voltage Vedlc exceeds the current restricting start voltage Vfu1 and is in the current restricting state B (described later, B = 1 is During the diaphragm operation, B = 0 indicates that the diaphragm is not operated.), A deviation unit 52 for obtaining a deviation output between the EDLC voltage Vedlc and the EDLC reference voltage Vfu, and the obtained deviation output are input. A standard calculation unit 53 that obtains a calculation output value as an output, a PI amplifier 54 that obtains a second current command value D from the obtained output value, an output from the sample hold device 55, and a first current command value A are given. The selector 56 includes a deviation unit 57 that takes a deviation between the output value C of the selector 56 and the second current command value D.

  The output value from the current restricting unit 50 (the output value from the deviation unit 57) is supplied to one terminal of the comparator 32, and the other terminal of the comparator 32 is subjected to restriction processing by the limiter 24. The first current command value A is supplied and the two are compared, and the comparator 32 sends the smaller one of the two values as the charge current command value. Subsequent processing is performed in the same manner as in the first embodiment.

  In the second embodiment configured as described above, when the EDLC voltage Vedlc exceeds the current throttling start voltage Vfu1, the current throttling operation is started.

There are three conditions (1) to (3) for ending current throttling.
(1) When the current throttle end voltage Vfu2 shown in FIG.
(2) When the command value by the feed voltage constant control falls below the current command value (output of the comparator 32),
(3) This is the case where it is determined that the EDLC, which is the power storage medium of the power storage device, is fully charged (since charging is stopped, the current throttling ends).

  Next, operations of the feeding voltage constant control unit 20 and the current restricting unit 50 according to the second embodiment will be described. As described above, the output of the controller 20 is the first current command value A, and the output of the determiner 51 is the determination output B of whether the EDLC voltage exceeds the current restriction start voltage Vfu1 or the current restriction state. When it is determined that 51 is “Vedlc> Vfu1 (current throttling start voltage)”, the determination output B is “1”, the PI amplifier 54 is in the current throttling operation, and the determiner 51 determines “Vedlc <Vfu2 (current When it is determined that it is “aperture end voltage)”, the determination output B becomes “0”, and the current aperture operation of the PI amplifier 54 is terminated (the aperture is not activated). However, Vfu1 ≧ Vfu2.

  Further, when the output of the selector 56 at the current restricting unit 50 by the EDLC voltage is “C”, the selector 56 is configured to select the input 1 when the determination output B is “0”. The output is “C = first current command value A”. Thereafter, when the judgment output B changes from “0 → 1”, the selector 56 selects the input 2 and the output of the selector 56 is “C” when the judgment output B changes from “0 → 1”. Is held by the sample hold device 55, and the output of the selector 56 holds the value "C".

  Furthermore, when the output of the PI amplifier 54 at the current restricting unit 50 by the EDLC voltage is the second current command value D, the second current command value D is output from the selector 56 at the deviation unit 57. The deviation from the value is taken, and the deviation output is supplied to the comparator 32, and the current throttling operation is performed with the second current command value D. This second current command value D is shown in the following equation. The second current command value D is a current command value output so that the EDLC voltage Vedlc performs PI (proportional integration) control with the current throttling start voltage Vfu1 as a target.

D = kp ^* (Vedlc−Vfu1) + ki ^* ∫ (Vedlc−Vfu1) dt
However, this is only during the period when the determination output B is “1”.

  FIG. 6 is a block diagram of a regenerative power absorption control block in constant current control showing Embodiment 3 of the present invention. In Embodiment 3, when EDLC approaches full charge in constant current control, only EDLC voltage Vedlc is used. This is a method for reducing the charging current. In FIG. 6, the same parts as those in FIGS. 1, 5, 12, and 13 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the third embodiment shown in FIG. 6, the constant current control unit 65 includes a limiter 24 to which a constant current command value from the constant current command unit is given. A current command value from the constant current control unit 65 is sent to the output of the limiter 24. The output value of the constant current control unit 65 is a first current command value A.

  In the case of constant current control, since the first current command value A and the output value C of the selector 56 in the second embodiment are the same value, in this third embodiment, the selection is made with the sample hold device 55 in the second embodiment. The vessel 56 is omitted.

  Reference numeral 66 in the figure denotes a current restricting unit based on an EDLC voltage. The current restricting unit 66 is provided with a determination unit 51, a deviation unit 52, a standard calculating unit 53, and a PI amplifier 54 as in the configuration of the second embodiment. A deviation unit 67 is provided for taking a deviation between the second current command value D obtained from the PI amplifier 54 and the first current command value A. The operation of the determiner 51 and the like is performed in the same manner as in the second embodiment.

  The output value from the current restricting unit 66 (the output value from the deviation unit 67) is supplied to one terminal of the comparator 32, and the other terminal of the comparator 32 receives the first current command from the limiter 24. The value A is supplied and the two are compared, and the comparator 32 sends the smaller one of the two values as the charge current command value. Subsequent processing is performed in the same manner as in the first embodiment.

  FIG. 7 is an explanatory diagram of the current restricting operation using only the EDLC voltage. In FIG. 7, the shaded area indicates the range where the current restricting is applied, Vfu1 is the current restricting start voltage, and Vfu2 is the current restricting end voltage.

  FIG. 8 is a diagram depicting a simulation feeding voltage constant control Iedlc-Vedlc locus in Example 2, where ST indicates a current throttling start voltage, CV indicates a charging upper limit voltage, and SP indicates a current throttling end voltage. From FIG. 8, it was confirmed that the EDLC voltage was reduced to the charge upper limit voltage CV by the current throttling only by the EDLC voltage.

DESCRIPTION OF SYMBOLS 1 ... Feed wire 6 ... Bidirectional chopper means 8 ... Electric double layer capacitor (EDLC)
DESCRIPTION OF SYMBOLS 10 ... Feeding current detection part 11 ... Feeding voltage detection part 12 ... EDLC current detection part 13 ... EDLC voltage detection part 21 ... Deviation part 22 ... Normalization calculating part 23 ... PI amplifier 24 ... Limiter 32 ... Comparator 34 ... EDLC Filter considering voltage drop due to internal resistance of

Claims (5)

An electric wire voltage compensator is provided to stabilize the feeder voltage by suppressing fluctuations in the feeder voltage that occurs during the regeneration and power running of electric vehicles in electric railways. The power converter is provided with a bidirectional chopper means, the electric power storage apparatus is provided with an electric double layer capacitor, and regenerative power from an electric vehicle is controlled by the bidirectional chopper means. In the charge control method for charging the electric double layer capacitor,
After obtaining the first deviation from the feed voltage detection value and the power reference voltage value, PI control is performed on the output of the first deviation to obtain a first current command value,
The charging current detection value and the charging voltage detection value of the electric double layer capacitor and the charging voltage upper limit value of the known electric double layer capacitor and the internal resistance value of the charging current detection value and the maximum charging current value at that time that is less than the charging voltage upper limit value A filter in which the maximum charging current value is equal to or higher than the charging current upper limit value of the electric double layer capacitor, and the charging current upper limit value is set as the second current command value in the following cases. Send out using
After comparing the first current command value and the second current command value obtained through the filter, the smaller one of the first and second current command values was obtained as the charge current command value. rear,
PI control is performed on the output of the second deviation between the charge current command value and the charge current detection value of the electric double layer capacitor, and a gate signal of the bidirectional chopper means is generated based on the PI control output. A charging control method for a feeder voltage compensator for an electric railway, wherein the bidirectional chopper means is gate-controlled by a gate signal to absorb regenerative power of the electric vehicle. 2. The charging control method for a feeder voltage compensator for an electric railway according to claim 1, wherein the maximum charging current value is obtained by the following equation.

An electric wire voltage compensator is provided to stabilize the feeder voltage by suppressing fluctuations in the feeder voltage that occurs during the regeneration and power running of electric vehicles in electric railways. The power converter is provided with a bidirectional chopper means, the electric power storage apparatus is provided with an electric double layer capacitor, and regenerative power from an electric vehicle is controlled by the bidirectional chopper means. In the charge control method for charging the electric double layer capacitor,
After obtaining the first deviation from the feed voltage detection value and the power reference voltage value, PI control is performed on the output of the first deviation to obtain a first current command value,
A second deviation between the charge voltage detection value of the electric double layer capacitor and its reference voltage value is obtained, and when the charge voltage detection value of the electric double layer capacitor exceeds the current throttling start voltage, the output of the second deviation is PI. A current throttle value by the electric double layer capacitor voltage obtained by control is obtained, and a value obtained by obtaining a third deviation between the current throttle value and the first current command value is defined as a second current command value.
After comparing the first current command value and the second current command value, after obtaining the smaller one of the first and second current command values as the charging current command value,
PI control is performed on the output of the fourth deviation between the charge current command value and the charge current detection value of the electric double layer capacitor, and the gate signal of the bidirectional chopper means is generated based on the PI control output. A charging control method for a feeder voltage compensator for an electric railway, wherein the bidirectional chopper means is gate-controlled by a gate signal to absorb regenerative power of the electric vehicle.   4. The charging control method for a feeder voltage compensator for an electric railway according to claim 3, wherein the second current command value controls a current throttle value so that the electric double layer capacitor does not become an overvoltage. An electric wire voltage compensator is provided to stabilize the feeder voltage by suppressing fluctuations in the feeder voltage that occurs during the regeneration and power running of electric vehicles in electric railways. The power converter is provided with a bidirectional chopper means, the electric power storage apparatus is provided with an electric double layer capacitor, and the bidirectional electric chopper means controls the regenerative power from the electric vehicle. In the charge control method for charging the electric double layer capacitor,
The constant current command value of the constant current command unit is obtained as the first current command value,
The first deviation between the charge voltage detection value of the electric double layer capacitor and its reference voltage value is obtained, and when the charge voltage detection value of the electric double layer capacitor exceeds the current throttling start voltage, the output of the first deviation is PI controlled. A value obtained by obtaining a second deviation between the current aperture value obtained by the electric double layer capacitor voltage and the first current command reference value as a second current command value,
After comparing the first current command value and the second current command value, after obtaining the smaller command value of both command values as the charging current command value,
PI control is performed on the output of the third deviation between the charging current command value and the charging current detection value of the electric double layer capacitor, and a gate signal of the bidirectional chopper means is generated based on the PI control output. A charging control method for a feeder voltage compensator for an electric railway, wherein the bidirectional chopper means is gate-controlled by a gate signal to absorb regenerative power of the electric vehicle.

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