JPS6277804A - Trolley bus driving device - Google Patents

Abstract

PURPOSE:To enable a trolley bus to travel by a low-pressure battery power source at the time of emergency traveling by providing a change-over switch which changes-over the DC input side of the inverter and a connection change- over means which changes-over the connection of the induction electric motor. CONSTITUTION:At the time of normal traveling, DC power is led in from a DC stringing 1 through a trolley pole 2 and the DC power is supplied to a variable voltage . variable frequency inverter 6 through a filter circuit consisting of a filter reactor 3 and a filter capacitor 4 and a change-over switch 5. In the case of emergency traveling, with a change-over of the change-over switch 5 to the side of a battery power source 12, an induction electric motor 7A is changed-over from a Y connection to a DELTA connection. Hereby, the emergency necessary tractive force characteristics can be satisfied.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a trolleybus driving device in which an induction motor provided as a main motor for driving a trolleybus is driven by a DC power source via an inverter. .

[Technical backstory of the invention and its problems]

As a trolley bus drive device of the above type, a structure shown in FIG. 4 is known. In this device, during normal running, DC power is taken from a DC overhead wire 1 via a trolley ball 2, and a filter circuit consisting of a filter reactor 3 connected in series and a filter capacitor 4 connected between the ground 11 and a switching DC power is supplied to a variable voltage/variable frequency (VVVF) inverter 6 via a switch 5 . The VVVF inverter 6 outputs an alternating current of a predetermined voltage and a predetermined frequency, and serves as an induction electric motor Ff! that is the main motor for driving the trolleybus. 17 is driven and controlled. Equipped with a DC lightning generator (9) driven by a diesel engine 8 for self-driving trolleybus operation, that is, emergency operation when the power supply from the DC overhead wire 1 is cut off for some reason, During emergency driving, by switching the changeover switch 5, the DC input to the VVvF inverter 6 is changed to DC power generation 1.
I'm trying to get everything from ffi9.

In this way, emergency driving is possible by fearing engine power generation, but for emergency driving only, not only the Deep Pill engine 8 and the DC generator 9 but also the fuel tank 11 that stores fuel for the Deep Pill engine is required. 10 had to be equipped, which caused a number of problems, such as loud noise from the driver's cabin, the need for a large space under the floor for the equipment, and an increase in the number of small items in the vehicle.

As a solution to these problems, it may be possible to install a battery power source instead of the engine generator, and this is currently used in some trolleybuses that use a DC motor as the main motor. However, this method is
Attempts to apply this to the induction type 1I71 aircraft drive system of V F Ill 111 do not necessarily go well.

In Figure 3, with respect to the traction force characteristic a required in an emergency, with a normal battery power source (approximately 48 to 60 V), only a small output as shown in the characteristics can be obtained from the induction motor, and there is a situation in which it is impossible to drive in an emergency. occured.

In order to be able to run, the output characteristics of the induction motor must be set to characteristic C.
1, that is, the voltage of the battery power source is set to 84 to 108 V, for example, so that it exceeds characteristic a within a predetermined running speed range.
You need to raise it to a certain level.

This occurs because the induction motor has a stall torque Δ as its characteristic, and is unique to induction motors. In other words, the voltage TR of the battery power source leads to an increase in capacity, which leads to the space and weight required for the battery power source, and further increases in the charging time when the battery is exhausted.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances, and it is an object of the present invention to provide a trolleybus drive device that can obtain emergency running characteristics with a relatively light emergency power source. It is.

[Summary of the invention]

In order to achieve the above object, the trolleybus drive device of the present invention includes an induction motor which is provided as a main electric motor for driving a trolleybus and whose wiring can be switched according to the power supply voltage, and which supplies AC driving power to the induction motor. an inverter, a changeover switch that selectively switches the DC input side of the inverter to the DC overhead line side or the lower voltage emergency battery power supply side; The present invention is characterized by comprising a wire connection switching means for switching the induction motor type wire connection.

(Embodiments of the invention) FIG. 1 shows an embodiment of the present invention.

In this device, from the DC overhead wire 1 to the VVVF inverter 6
The circuit portion up to is basically the same as that shown in FIG. The difference between the device in Figure 1 and the device in Figure 4 is that a battery power source 12 is used as the emergency running power source, and the connection can be switched between star connection (Y connection) and triangular connection (Δ connection). In order to control the switching of the changeover switch 5 and the connection of the induction motor FR7A, a switch command circuit 16 is sent to the microcomputer control unit 14 that controls the VVVF inverter. and that the Y-Δ switching command circuit 13 is connected as an interface.

In the device shown in FIG. 1, during emergency driving, the microcomputer control unit 14
The changeover switch 5 is switched to the battery power supply 12 side via the changeover switch command circuit 16 based on the command from the changeover command circuit 16, and the induction motor 7A is switched from the Y connection to the Δ connection through the Y-Δ changeover command circuit 13. . Due to the latter switching, the phase voltage of the electric motor □7A becomes 73 times the voltage before switching. Therefore, even when switching to the battery power source 12 side, the output characteristics of the induction electric motor 17A can easily be brought close to the characteristics C in FIG.

To return to the normal state where power is received from the DC overhead wire 1, the microcomputer control unit 14 must be used to control the induced lightning! , IJ If 7 A should be switched to the Y connection side, and the changeover switch 5 should be switched to the DC overhead wire 1 side.

In the embodiment shown in FIG. 1, the wiring connections for each induction lightning IJ are switched between Y and Δ, so the phase voltage switching ratio is 1:V3. This switching of the phase voltage can also be achieved by forming each phase winding from a plurality of intermediate windings, and switching the unit windings into series, parallel, or series-parallel depending on the switching of the changeover switch 5. can do. An example of this is shown in FIG. 2 in the case of a Y connection.

In the device shown in FIG. 2, each phase winding of the Y-connected induction motor 7B is composed of two sets of unit windings, and the 1Y-2Y switching command circuit 15 is controlled by a command from the microcomputer control section 14. When receiving power from the DC overhead line 1, connect the wires in series.
1Y), and when receiving power from the battery power supply 12, the connection is switched to parallel connection, that is, double Y connection (2Y), and the switching ratio of phase voltage or magnetomotive force is 1:2.
becomes.

Irrespective of whether it is a Y-connection or a H-connection, a magnetomotive force switching ratio of 1:n can generally be obtained by switching 0 sets of unit windings in series and parallel. In addition, any switching ratio (q) can be achieved by any series/parallel switching.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to run on a lower voltage battery FF power source without depending on the engine power generation during emergency driving, and the effect of reducing the size and weight of vehicles with large installation space constraints is significant. It is what it is.

[Brief explanation of drawings]

1 and 2 are circuit diagrams showing different embodiments of the present invention,
FIG. 3 is a characteristic diagram for explaining the traction force characteristics of the induction motor, and FIG. 4 is a circuit diagram of a conventional trolleybus drive device. 1...δ overhead line, 2...trolley bus, 5...changeover switch, 6...variable voltage/variable frequency inverter, 7Δ, 7B...induction motor, 12...battery power source. Applicant's agent Mr. Sato - Engraving of the drawings (no changes in content) Figure 1 Figure 4 Procedural amendment dated October 58, 1985

Claims (1)

[Claims] An induction motor is provided as the main motor for driving the trolleybus and the wiring can be switched according to the power supply voltage, an inverter supplies AC drive power to this induction motor, and the DC input side of this inverter is connected to the DC overhead wire side or lower voltage. A changeover switch that selectively switches to the emergency battery power source side of the inverter, and a connection switching means that changes the connection of the induction motor in accordance with the input voltage of the inverter that corresponds to the switching position of the changeover switch. Trolleybus drive device.