JP3290949B2 - Vehicle control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle control device for a railway vehicle driven by a three-phase AC induction motor.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing the configuration of a conventional vehicle control device disclosed in, for example, Japanese Patent Application Laid-Open No. 6-22441. In FIG. 2, DC power supplied from a DC power supply 1 is converted into three-phase AC power by a power converter 2 such as an inverter, and supplied to a plurality of three-phase induction motors 3a to 3d connected in parallel. From the phase currents detected by the current detection means 4a to 4c, only the fundamental wave component is extracted via the band-pass filters 5a to 5c. Then, the maximum current detection means 6a to 6c detect and store the maximum values A, B, and C of each phase during a period T in which the maximum value appears in each phase as shown in FIG.

Further, the unbalance detecting means 7 compares the maximum current values A, B, and C of each phase. Usually, as shown in FIG.
Since the maximum values A, B, and C of the respective phase currents have the same value, no difference between the maximum values A, B, and C is detected. For example, when the W-phase connection line is disconnected between the power converter 2 and the induction motors 3a to 3d, the load impedance of the W-phase increases, so that the maximum value C of the W-phase current as shown in FIG. Becomes smaller. As a result, the unbalance detecting means 7 detects the difference between the healthy U-phase and the V-phase maximum value. When the detected difference current value becomes larger than a predetermined set value, the unbalanced phase current is detected by the unbalance detecting means 7.

[0004]

Since the conventional vehicle control device is configured as described above, it is necessary to monitor during the period T to detect the maximum value of each phase current.
The detection time is long. For this reason, there is a problem in that shutting off the power converter from the power supply is delayed and the accident may be expanded.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a vehicle control apparatus capable of shortening the time required to detect phase imbalance. .

[0006]

According to a first aspect of the present invention, there is provided a vehicle control device for controlling a driving induction motor by using a variable frequency and a variable voltage AC power output from a power converter. In the apparatus, a current detecting means for detecting a phase current of the induction motor, an operation circuit for performing a vector operation of an instantaneous value of the torque of the induction motor based on a command voltage and a phase current for the induction motor, and a high-frequency ripple component of the calculated torque Is provided with an unbalance detection means for outputting an unbalance detection signal when exceeds a predetermined set value.

According to a second aspect of the present invention, there is provided a vehicle control device, wherein the power converter includes a converter for converting an AC power supply to DC power and an inverter for converting DC power to AC power.

According to a third aspect of the present invention, the power converter is an inverter that converts DC power supplied from a DC power supply into AC power.

According to a fourth aspect of the present invention, the power converter is stopped by an unbalance detection signal.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a configuration diagram of the first embodiment. In FIG. 1, reference numeral 8 denotes a three-phase AC power supply, and 9 denotes an opening / closing means, which is connected between a power converter 13 and an AC power supply 8 described later. Reference numeral 10 denotes a converter connected to the AC power supply 8 via the opening / closing means 9, and outputs a predetermined DC voltage. Reference numeral 11 denotes an inverter to which power is supplied from the converter 10, and outputs AC power having a variable frequency and a variable voltage. Reference numeral 12 denotes a filter capacitor connected to the input side of the inverter 11. The power conversion device 13 is constituted by 10 to 12. Induction motors 14 to 17 are connected in parallel to the power converter 13, and are provided for each axle on which wheels are mounted.

Reference numerals 18 to 25 denote current detecting means such as DC current transformers for detecting the phase currents of the induction motors 14 to 17 and outputting phase current signals 18a to 25a, respectively. Reference numeral 26 denotes a modulation factor calculation circuit having a table which determines the relationship between the command frequency to the inverter 11 and the output voltage of the power converter 13, and a notch signal 27 and a speed of each of the induction motors 14 to 17 commanded from the cab. A command voltage signal 26a and a frequency signal 26b are output based on a frequency signal input from a detection unit (not shown). 28 is a gate pulse generation circuit,
The gate pulse signal 28a is output to the inverter 11 according to the command voltage signal 26a and the frequency signal 26a.

Reference numerals 29 to 32 denote command voltage signals 26a, respectively.
A torque calculation circuit to which the phase current signals 18a to 25a are input calculates the instantaneous values of the torque of the induction motors 14 to 17 by vector calculation and outputs torque signals 29a to 32a. Reference numerals 33 to 36 denote high-pass filters that extract high-frequency ripple components included in the torque signals 29a to 32a when the induction motors 14 to 17 are out of phase, and output ripple signals 33a to 36a. Reference numerals 37 to 40 denote comparison means having a set value having a threshold value of, for example, 20% of the maximum torque generated by the induction motors 14 to 17,
When 3a to 36a exceed the set value, the comparison detection signal 37a
To 40a are output.

Reference numeral 41 denotes an OR circuit, which includes comparison detection signals 37a to 37a.
The logical sum of 40a is output as the unbalance detection signal 41a. The unbalance detecting means 42 is composed of 37 to 41. Reference numeral 43 denotes a logic circuit to which the unbalance detection signal 41a is input. The control signal 43a is output by the unbalance detection signal 41a, and the opening of the opening / closing means 9 and the gate stop of the converter 10 and the inverter 11 are commanded.

Next, the operation will be described. In FIG. 1, a converter 10 is connected from an AC power supply 8 through an opening / closing means 9.
Is supplied with AC power. The voltage is converted into a predetermined DC voltage by a converter 10 and further converted into AC power by an inverter 11 having a variable frequency and a variable voltage. Then, AC power is supplied from the inverter 11 to the plurality of induction motors 14 to 17 connected in parallel. As a result, the induction motors 14 to
17 drives each axle to propel the vehicle.

Here, the phase current detected by each of the current detecting means 18 to 25 is separated into an excitation component and a torque component, and the current for the torque and the command voltage signal 26a from the modulation factor calculating circuit 26 are separated.
As a result, the instantaneous value of the generated torque is
A vector operation is performed at 32. When the induction motors 14 to 17 are operating properly, the unbalanced detection signal 41a is not detected because the high-frequency ripple included in the generated torque is equal to or less than the set value of the comparing means 37 to 40.

For example, if the W phase of the induction motor 14 is lost due to disconnection or the like, a pulse-like ripple is generated at the frequency cycle of the power conversion device 13.
9 includes a ripple component in the torque signal 29a. The ripple included in the torque signal 29a is extracted by the high-pass filter 33 and input to the comparing means 37. Then, when the comparing means 37 determines that the ripple exceeds the set value, a comparison detection signal 37a is output, and the OR circuit 41 outputs an unbalance detection signal 41a. The logic circuit 43 outputs the control signal 43a in response to the unbalance detection signal 41a, instructs the gate stop of the converter 10 and the inverter 11, stops the power converter 13, and opens the switching means 9 to open the power converter 13. From the AC power supply 8.

As described above, the instantaneous value of the generated torque is calculated by the vector calculation, and the unbalanced detection is performed by comparing the ripple included in the generated torque with the set value. Can be suppressed.

In the above configuration, the power converter 13 is constituted by the converter 10, the inverter 11 and the filter capacitor 12, and the AC power is supplied from the AC power supply 8. However, the power converter is constituted by the inverter. The same effect can be expected even if DC power is supplied from the DC power supply to the inverter.

Although the description has been given of the case where a plurality of induction motors 14 to 17 are connected to the power converter 13, the same effect can be expected even when only one induction motor is used.

[0020]

According to the first aspect of the present invention, the instantaneous value of the generated torque is calculated by the vector calculation, and the unbalance detection is performed by comparing the ripple included in the generated torque with the set value. It is possible to shorten the time and suppress the spread of the accident.

According to the second aspect of the present invention, since the power converter is constituted by the converter for converting the AC power into DC power and the inverter for converting the DC power into AC power, the power is stabilized from the AC power. AC power can be obtained.

According to the third aspect of the present invention, since the power converter is an inverter that converts DC power supplied from a DC power supply into AC power, stabilized AC power can be obtained from DC power. .

According to the fourth aspect of the present invention, since the power conversion device is stopped by the unbalance detection signal, it is possible to prevent an accident from spreading.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a conventional vehicle control device.

FIG. 3 is an explanatory diagram showing the operation of FIG. 2;

FIG. 4 is an explanatory diagram showing the operation of FIG. 2;

[Explanation of symbols]

8 AC power supply, 10 converter, 11 inverter,
13 Power conversion device, 14-17 Induction motor, 18-
25 current detecting means, 29 to 32 torque calculation circuit, 4
2 Unbalance detection means.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60L 9/00-9/32

Claims (4)

(57) [Claims] 1. A vehicle control device for controlling a drive induction motor with variable frequency and variable voltage AC power output from a power conversion device, wherein current detection means for detecting a phase current of the induction motor is provided. A torque calculation circuit that performs a vector calculation of the instantaneous value of the torque of the induction motor based on the command voltage and the phase current for the induction motor, and a high-frequency ripple of the calculated torque exceeds a predetermined set value. An unbalance detection means for outputting an unbalance detection signal. 2. The vehicle according to claim 1, wherein the power converter comprises a converter for converting the AC power into DC power, and an inverter for converting the DC power into AC power. Control device. 3. The control device for a vehicle according to claim 1, wherein the power conversion device is an inverter that converts DC power supplied from a DC power supply into AC power. 4. The vehicle control device according to claim 1, wherein the power conversion device is stopped by an unbalance detection signal.