JP4196543B2 - Vehicle drive device and train system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle drive device that enables protection of a filter reactor mounted on an electric vehicle, and more particularly to a train system that includes a plurality of vehicles mounted with a vehicle drive device in a train.
[0002]
[Prior art]
An ordinary train system includes a plurality of vehicles equipped with a vehicle drive device in a train, and travels using both a regenerative brake and a power generation brake.
[0003]
FIG. 11 is a diagram illustrating an example of a vehicle drive device for explaining the related art. In FIG. 11, when the vehicle drive device is powered, a current flows from the overhead line 1 to the inverter 5 that is a drive device via the pantograph 2, the switch 3, and the filter reactor 4, and the motors 61 to 64 are respectively driven. During regenerative braking, current flows from the inverter 5 to the overhead wire 1 through the path of the filter reactor 4, the switch 3, and the pantograph 2. Between the wheel 7 and the filter reactor 4, a resistor 8 for power generation brake and a switching element 9 are provided in series.
[0004]
A current flows through the filter reactor 4 as the train repeats the power running operation and the regenerative operation. When an input current flows through the filter reactor 4, heat loss occurs based on the magnitude of the winding resistance, and the temperature rises. Therefore, conventionally, the capacity of the filter reactor 4 is determined so that the filter reactor 4 does not overheat, assuming the maximum case in train operation.
[0005]
[Problems to be solved by the invention]
Therefore, in a train system including a plurality of vehicles equipped with the above-described vehicle drive device in the formation, it is necessary to determine the capacity of the filter reactor on the assumption that the train operation rarely occurs, and therefore, The conventional vehicle drive device has a problem that it is large and heavy. In addition, if the capacity of the filter reactor is determined on the assumption that each vehicle unit is healthy, the filter reactor will be damaged if the current flowing through the filter reactor is not reduced when an overload is detected. There was also.
[0006]
An object of the present invention is to provide a vehicle drive device to which a small and lightweight filter reactor is applied.
Another object of the present invention is to provide a vehicle drive device and a train system that can reliably detect overheating of a filter reactor.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a vehicle drive device including a filter reactor, an inverter device, and an electric motor is provided. The vehicle drive device includes: an overheat detecting unit that detects overheating of the filter reactor; and a current reducing unit that reduces an electric current flowing through the filter reactor when the overheating of the filter reactor is detected by the overheat detecting unit. Composed.
[0008]
In this vehicle drive device, the capacity of the filter reactor can be determined not by determining the capacity of the filter reactor under special operational conditions, but by the duty that occurs during normal operation.
[0009]
There is also provided a train system that includes a plurality of vehicles equipped with a vehicle drive device in the formation. This train system detects overheating of the filter reactor in the remaining vehicles and reduces the current of the filter reactor when one or more vehicle drive devices of the vehicle being organized are cut out. The overheat of each filter reactor is prevented.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1A is a block diagram showing a protection device for detecting overheating of a filter reactor, and FIG. 1B is a diagram for explaining the detection operation. Here, the average value of the current flowing through the filter reactor is calculated to detect overheating of the filter reactor.
[0011]
In FIG. 1A, the current flowing through the filter reactor 4 is detected by CT11. The current value detection circuit 12 is connected to an average value calculation circuit 13 where the average value of the current flowing through the filter reactor 4 is calculated. The average value of the current flowing through the filter reactor 4 is compared with a predetermined threshold value by the comparator 14. The comparator 14 is connected to the threshold setting circuit 15 and outputs an overheat detection signal when a current flows through the filter reactor 4 exceeding the set threshold. The pantograph 2, the filter reactor 4, the inverter 5, the electric motors 61 to 64, and the wheels 7 are the same as the conventional example of FIG.
[0012]
Now, let the current value flowing through the filter reactor 4 be IL, and the magnitude of the resistance component of the filter reactor 4 be RL. Then, the loss PL generated in the filter reactor 4 can be expressed by the following equation (1).
[0013]
PL = IL ² × RL (1)
That is, the loss PL generated in the filter reactor 4 is a product of the square value of the current flowing through the filter reactor 4 and the resistance component of the filter reactor 4. Here, as shown by the above-described equation (1), an overload in the vehicle drive device is utilized by utilizing the fact that the loss (heat generation amount) generated in the filter reactor 4 is proportional to the square of the current value flowing through the filter reactor 4. A state is detected.
[0014]
In FIG. 1B, the horizontal axis represents time t, and the vertical axis represents current value IL. In the average value calculation circuit 13, the input current indicated by the dotted line is sampled for a certain period of time, and the average value of the current flowing through the filter reactor 4 is calculated. The calculation result is indicated by a solid line in FIG. In the comparator 14, the average value is compared with a threshold value indicated by a one-dot chain line, and an overheat detection signal is output.
[0015]
As described above, in the protection device shown here, the average value of the current flowing through the filter reactor 4 exceeds a predetermined threshold value, so that the overload state in the vehicle drive device is known by knowing the overheat state of the filter reactor 4. The state can be detected.
(Second embodiment)
FIG. 2A is a block diagram showing a protection device that detects the overheat of the filter reactor by calculating the effective value of the current flowing through the filter reactor, and FIG. 2B is a diagram for explaining the detection operation. is there.
[0016]
In FIG. 2A, the current flowing through the filter reactor 4 is detected by the CT 11. The current value detection circuit 12 is connected to the effective value calculation circuit 21 where the effective value of the current flowing through the filter reactor 4 is calculated. The magnitude of the effective current of the filter reactor 4 is obtained by squaring the input current when the current value detected by the CT 11 is IL, taking the product with time, and further calculating the route (IL ² × t ) ^1/2 . The output of the effective value calculation circuit 21 is supplied to the first-order lag calculation circuit 22, and the first-order lag calculation result is compared with a predetermined threshold value by the comparator 14. The comparator 14 is connected to the threshold setting circuit 15 and outputs an overheat detection signal when a current flows through the filter reactor 4 exceeding the set threshold. The pantograph 2, the filter reactor 4, the inverter 5, the electric motors 61 to 64, and the wheels 7 are the same as the conventional example of FIG.
[0017]
In FIG. 2B, the horizontal axis represents time t, and the vertical axis represents the magnitude of the effective current of the filter reactor 4 subjected to the first-order lag correction. When the effective current indicated by the dotted line is output from the effective value calculation circuit 21, the first-order delay calculation circuit 22 performs a first-order delay calculation of 1 / (1 + sT) based on the thermal time constant T of the filter reactor 4. By performing overheat detection using a value obtained by calculating the first-order lag with the thermal time constant T with respect to the effective value calculation result, the calculation accuracy of the temperature estimation of the filter reactor 4 can be improved. This is because even if a constant effective current flows through the filter reactor 4, the temperature rises with a delay determined by the time determined by the thermal time constant. The first-order lag calculation result is indicated by a solid line in FIG. In the comparator 14, this value is compared with a threshold value indicated by a one-dot chain line, and an overheat detection signal is output.
[0018]
As described above, in the protection device shown in the second embodiment, the effective value of the current flowing through the filter reactor 4 exceeds a predetermined threshold value, so that the overheat state of the filter reactor 4 is known and the vehicle is driven. An overload condition in the device can be detected.
(Third embodiment)
FIG. 3A is a block diagram showing a protection device showing an arithmetic system in which the arithmetic operation in the second embodiment is simplified, and FIG. 3B is a diagram for explaining the detection operation.
[0019]
In the second embodiment, the overload state of the filter reactor 4 is detected by calculating the effective value, but here, the root operation is not performed, and the overheat state is detected only by the square calculation. It is. A difference from FIG. 2A is that a square calculation circuit 31 is used instead of the effective value calculation circuit 21. If the RMS calculation is performed every second, the multiplication with the time t is also omitted.
[0020]
As described above, the value obtained by calculating the first-order lag by the first-order lag calculation circuit 22 with respect to the value obtained by squaring the current value flowing through the filter reactor 4 is obtained. An overload condition in the device can be detected. Therefore, compared with the second embodiment, the accuracy of temperature estimation of the filter reactor 4 is improved, and erroneous detection that the filter reactor 4 is overheated can be reduced.
(Fourth embodiment)
Conventionally, as shown in FIG. 11, the switch 3 switches from the power running mode to the regenerative mode and the direction of the current flowing through the filter reactor 4 is switched to reduce the speed of the train driven by the vehicle drive device. A description will be given of current reducing means for reducing the current flowing through the filter reactor 4 when overheating of the filter reactor 4 is detected by the overheat detecting means after switching to the regeneration mode.
[0021]
FIG. 4 is a diagram showing the configuration of the current reducing means. Here, not only a brake mode by power regeneration as shown in FIG. 4 (A) but also a power generation brake (brake by power consumption at resistor 8) mode as shown in FIG. 4 (B) can be selected. . In the power generation brake mode, no regenerative current flows through the filter reactor 4. Therefore, when overheating in the filter reactor 4 is detected, the duty of the filter reactor 4 can be reduced by selecting the power generation brake mode by the mode switching control. FIG. 3C shows the configuration of the current reducing means. The configuration of the overheat detection circuit of the filter reactor 4 may be any of the first to third embodiments. Here, the mode switching control is executed based on the overheat detection signal, and the brake mode can be selected according to the overload state in the vehicle drive device without increasing the temperature of the filter reactor 4.
[0022]
Note that it is possible to select an air brake as the brake mode, and the same duty reduction effect can be obtained by the mode switching control for switching to the air brake mode instead of the power consumption by the resistor 8.
(Fifth embodiment)
Next, a description will be given of current reducing means that switches the power running mode to reduce the filter reactor current.
[0023]
FIG. 5 is a diagram for explaining a method of switching the power running mode. In FIG. 5A, the speed when the filter reactor current is not reduced is indicated by a solid line, and the speed when the filter reactor current is reduced is indicated by a broken line. FIG. 4B shows the corresponding output torque states. Further, FIG. 3C shows the state of the filter reactor current. In order to reduce the current flowing through the filter reactor 4 during power running, the output torque of the inverter may be reduced.
[0024]
Since the output P of the electric motor is the product of the output Tr and the vehicle speed ω, if the filter reactor current is I and the input voltage is V,
P = V × I = Tr × ω (2)
It becomes. Therefore, the input current I is proportional to the output torque Tr of the inverter, as shown by the following equation (3).
[0025]
I = Tr · ω / V (3)
From equation (3), Tr can be reduced to reduce the current I flowing through the filter reactor 4.
[0026]
Assuming that the number of revolutions of the motor is N, as shown in FIGS. 5A to 5C, the constant torque region from time t0 to t1, the constant output region from time t1 to t2, and the characteristic after time t2 are characteristic. The case where the torque indicated by the solid line is output is a pattern in the case where there is no reduction in the current flowing through the filter reactor 4. On the other hand, as indicated by a broken line, by reducing the torque of the motor at 1 / N ² at time t1, the current flowing through the filter reactor 4 during powering decreases from 1 to N from time t1. . Thereby, the duty of the filter reactor 4 can be reduced even during powering.
[0027]
FIG. 5D shows the configuration of the current reducing means. The configuration of the overheat detection circuit of the filter reactor 4 may be any of the first to third embodiments. Here, the mode switching control is executed based on the overheat detection signal, and the power running mode can be selected according to the overload state in the vehicle drive device without increasing the temperature of the filter reactor 4.
(Sixth embodiment)
Next, a train system that includes a plurality of vehicles equipped with the vehicle drive device described above in the formation will be described.
[0028]
As already described, in the conventional filter reactor 4, the capacity is determined in the maximum case in train operation so that the filter reactor 4 is not overheated. For this reason, there existed a subject that a filter reactor became large and heavy. As a case where the current flowing through the filter reactor increases during train operation, the following unit is open.
[0029]
FIG. 6 shows the configuration of a train of six cars and one train. Of these, the vehicle M is an electric vehicle whose wheels are driven by an electric motor. The vehicle T is a trailer vehicle, and no electric motor is attached to the carriage. The six-car train shown here constitutes a train system composed of 4M2T.
[0030]
By the way, when the power converter for driving the electric motor attached to one vehicle M fails, the vehicle configuration becomes 3M3T. When the power conversion device fails in two vehicles, the vehicle configuration is 2M4T. The driving force of the train decreases according to the ratio of the MT ratio. And if MT ratio falls, a filter reactor will be in an overload state for the reason described below.
[0031]
FIG. 7 is a diagram illustrating an operation mode. Even when 2M4T is achieved by opening the vehicle unit, the area in the speed-time curve must be the same for the train to travel between stations in the same time. For this reason, when the propulsive force decreases due to the opening, the power running time is extended according to the decreased ratio. As a result, the average current flowing through the filter reactor increases. When operation is continued with the average current between the stations increased, the temperature of the filter reactor itself rises, and the filter reactor reaches an overheated state.
[0032]
In this embodiment, an overheat detecting means for predicting the occurrence of overheating of the filter reactor will be described because one or more vehicle drive devices are opened.
[0033]
FIG. 8 is a block diagram showing a protection device for detecting overheating of the filter reactor in each vehicle. Speed detectors 71 to 74 are connected to the electric motors 61 to 64 constituting the driving device of the vehicle, respectively, and output speed signals to the acceleration detection circuit 75. The acceleration detection circuit 75 is supplied with a power running notch signal and an idling detection signal, and calculates and outputs an acceleration during power running. The comparator 76 compares the calculated acceleration with a predetermined threshold value. A threshold value setting circuit 77 is connected to the comparator 76, and when the acceleration decreases and falls below the set threshold value, an excessive current flows through the filter reactor 4, and an overheat detection signal is output. Output.
[0034]
The pantograph 2, the filter reactor 4, the inverter 5, the electric motors 61 to 64, and the wheels 7 are the same as the conventional example of FIG.
In the protection device having the above-described configuration, it is possible to predict that the filter reactor 4 is overheated because the drive device is opened. That is, in the case of a train, the torque corresponds to the power running notch. When the number of healthy units decreases due to a failure or the like, it is directly reflected in the acceleration. In the constant torque region from when the torque startup is completed until the constant output is obtained, the acceleration α is expressed by the following equation (4).
[0035]
α = Tr / M (4)
Here, M is the mass of the vehicle, and Tr is the torque.
In the constant torque region, for example, when the number of healthy units is halved, the acceleration is also halved. Therefore, it is possible to detect that the unit has been released from the acceleration in the constant torque flow region. The acceleration signal can be obtained by obtaining a speed signal using a speed sensor attached to the motor as described above and differentiating it. For example, if it is detected that the propulsive force is halved, a threshold value between 1 and 1/2 is set when the acceleration determined from the performance of the train is set to 1, and the threshold value is calculated by calculation. The overheat detection signal may be output by comparing with the acceleration. In the above-described embodiment, the idling control signal of the vehicle is input to the comparator 76, and if the torque falls below a predetermined torque during idling control, the calculation of acceleration is not performed and the calculation accuracy is improved. I have to.
(Seventh embodiment)
Next, a train system that predicts overheating by mutually transmitting unit failure signals between units will be described.
[0036]
FIG. 9 is a diagram showing a train system including four vehicle units M1 to M4 equipped with a vehicle drive device in the formation. For example, the vehicle unit M1 transmits its own failure signal to the other vehicle units M2 to M4 as stop information, and communicates with each other. The failure signals from the vehicle units M2 to M4 are received as vehicle stop information.
[0037]
When there are two or more vehicle units that have stopped due to failure and the remaining number of healthy units is two or less, the propulsive force is reduced to less than half and the power running time is increased. And overheated. Here, the overheat detection circuit 90 of the vehicle unit M1 is a logic circuit including three AND gates 91 to 93 and one OR gate 94. The overheat detection circuit 90 can detect overheating of the filter reactor 4 based on an output signal from the OR gate 94 when two or more vehicle units are stopped due to failure.
(Eighth embodiment)
Next, a train system that predicts overheating by transmitting unit opening signals to each other will be described.
[0038]
FIG. 10 is a diagram showing a train system that includes four vehicle units M1 to M4 mounted with a vehicle drive device in a train. Each vehicle unit is configured to communicate with each other the release signals from the other vehicle units. For example, the vehicle unit M1 transmits its own release signal to the other vehicle units M2 to M4 as stop information. Open signals from the vehicle units M2 to M4 are received as stop information.
[0039]
As in the seventh embodiment, when there are two or more vehicle units that have failed and stopped, and the remaining number of units is two or less, the propulsive force is reduced to less than half and the power running time increases. The filter reactor is overloaded and may overheat. Here, the overheat detection circuit 100 of the vehicle unit M1 is a logic circuit including three AND gates 91 to 93 and one OR gate 94. The overheat detection circuit 100 can detect the overheat of the filter reactor by the output signal from the OR gate 94 when two or more vehicle units fail and stop.
[0040]
【The invention's effect】
As described above, according to the train system of the present invention, the capacity of the filter reactor is determined not by determining the capacity of the filter reactor under special operational conditions, but by the duty that occurs in normal operation. be able to. Accordingly, it is possible to reduce the size and weight of the filter reactor.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a protection device for detecting overheating of a filter reactor.
FIG. 2A is a block diagram illustrating a protection device that calculates an effective value of a current flowing through a filter reactor and detects overheating of the filter reactor, and FIG. 2B is a diagram illustrating a detection operation thereof. .
FIG. 3A is a block diagram showing a protection device showing an arithmetic system that simplifies calculation, and FIG. 3B is a diagram for explaining the detection operation;
FIG. 4 is a diagram illustrating a method for switching a brake mode in order to reduce a current flowing through a filter reactor.
FIG. 5 is a diagram for explaining a method of switching a power running mode.
FIG. 6 is a diagram showing a configuration of a train of 6 cars and 1 train.
FIG. 7 is a diagram illustrating an operation mode.
FIG. 8 is a block diagram showing a protection device for detecting overheating of the filter reactor in each vehicle.
FIG. 9 is a diagram showing a train system according to a seventh embodiment.
FIG. 10 is a diagram showing a train system according to an eighth embodiment.
FIG. 11 is a diagram showing an example of a vehicle drive device for explaining a conventional technique.
[Explanation of symbols]
11 ... CT
DESCRIPTION OF SYMBOLS 12 ... Current value detection circuit 13 ... Average value calculation circuit 14 ... Comparator 15 ... Threshold value setting circuit 21 ... Effective value calculation circuit 22 ... Primary delay calculation circuit 31 ... Square calculation circuit

Claims (11)

In a vehicle drive device including a filter reactor, an inverter device, and an electric motor,
An overheat detecting means for calculating an average value of the current flowing through the filter reactor, and detecting an overheat of the filter reactor by the average value of the current exceeding a predetermined threshold ;
Current reduction means for reducing the current flowing through the filter reactor when the overheating of the filter reactor is detected by the overheat detection means;
A vehicle drive device comprising: In a vehicle drive device including a filter reactor, an inverter device, and an electric motor,
  The effective value of the current flowing through the filter reactor is calculated, and the value obtained by calculating the first-order lag of the effective value of the current with the thermal time constant of the filter reactor exceeds a predetermined threshold value. Overheat detecting means for detecting overheating of the filter reactor;
  Current reduction means for reducing the current flowing through the filter reactor when the overheating of the filter reactor is detected by the overheat detection means;
  A vehicle drive device comprising: In a vehicle drive device including a filter reactor, an inverter device, and an electric motor,
  The value obtained by multiplying the square value of the current flowing through the filter reactor by the time and calculating the first order lag with the thermal time constant of the filter reactor exceeds a predetermined threshold value. Overheating detection means for detecting overheating of the filter reactor,
  Current reduction means for reducing the current flowing through the filter reactor when the overheating of the filter reactor is detected by the overheat detection means;
  A vehicle drive device comprising: In a vehicle drive device including a filter reactor, an inverter device, and an electric motor,
  Overheat detecting means for detecting overheating of the filter reactor;
  When the overheating of the filter reactor is detected by the overheat detecting means, the current reducing means for reducing the current flowing through the filter reactor by stopping the regenerative brake in the filter reactor and switching to the power generation brake,
  A vehicle drive device comprising: In a vehicle drive device including a filter reactor, an inverter device, and an electric motor,
  Overheat detecting means for detecting overheating of the filter reactor;
  When the overheat of the filter reactor is detected by the overheat detection means, the current reduction means for reducing the current flowing through the filter reactor by stopping the regenerative brake in the filter reactor and switching to the air brake;
  A vehicle drive device comprising: In a vehicle drive device including a filter reactor, an inverter device, and an electric motor,
  Overheat detecting means for detecting overheating of the filter reactor;
  Current reduction means for reducing the current flowing through the filter reactor by lowering the torque output of the inverter device during power running when overheating of the filter reactor is detected by the overheat detection means;
  A vehicle drive device comprising: A filter reactor, an inverter device, and an electric motor, and an overheat detecting means for detecting overheating of the filter reactor, and when the overheat of the filter reactor is detected by the overheat detecting means, a current flowing through the filter reactor is reduced. In a train system including in a train a plurality of vehicles equipped with a vehicle drive device having a current reduction means,
  When a vehicle drive device is cut out in one or more of the vehicles in formation, the filter reactor overheat is detected, and the current of the filter reactor is reduced, thereby reducing the filter reactor in the remaining vehicles. A train system characterized by preventing overheating. The overheat detecting means includes
  A device that transmits and receives a failure signal between a plurality of vehicles, detects the number of vehicles that are stopped due to the failure signal, and detects overheating of the filter reactor in each vehicle;
  The train system according to claim 7, wherein: The overheat detecting means includes
  Furthermore, a speed sensor attached to the electric motor, and a differentiation circuit that obtains acceleration by differentiating the traveling speed detected by the speed sensor,
  The train system according to claim 8, wherein overheating of the filter reactor is detected when an acceleration becomes a predetermined acceleration value or less for each vehicle. The overheat detecting means includes
  A unit opening signal indicating that the vehicle drive unit has been opened due to a failure is exchanged between a plurality of vehicles, and the number of vehicles that have failed and stopped is detected by the unit opening signal, and overheating of the filter reactor is detected in each vehicle. What to do,
  The train system according to claim 7, wherein: The overheat detecting means includes
  Furthermore, a speed sensor attached to the electric motor, and a differentiation circuit that obtains acceleration by differentiating the traveling speed detected by the speed sensor,
  11. The train system according to claim 10, wherein overheating of the filter reactor is detected when an acceleration is equal to or lower than a predetermined acceleration value for each vehicle.

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