JPS59185102A - Controlling method of ac electric railcar - Google Patents

Abstract

PURPOSE:To eliminate DC magnetic deviation of a transformer, to facilitate the operation and to improve the running speed of an electric railcar by forcibly energizing an SCR in conductive state when a trolley wire is deenergized or interrupted. CONSTITUTION:A current controller 12 has a comparator 12a for comparing a current limiting vlaue instructed from a master controller 10 or the like with the output of a current detector 7 for detecting the current flowed to a motor, a phase unit 12b for deciding the control phase angle of an SCR by using the output of the comarator 12a and the output of a synchronizing power source 9, and a firing circuit 12c for applying a firing signal to the SCR of a rectifier 3, and the output of a trolley wire voltage detector 11 is applied to the circit 12c. Accordingly, the all SCRs 3a-3d of the rectifier 3 become conductive by the firing angle from the circuit 12c, the current flowed to a transformer 2 becomes zero, and it can prevent the application of a DC magnetic deviation.

Description

[Detailed Description of the Invention] This invention relates to a control method for an AC electric train that performs phase control using a rectifier composed of a pure Sirisk bridge, particularly when passing through an unpressurized section (alternate section) of an overhead wire. Alternatively, it relates to a control method when the overhead line suddenly becomes unpressurized, such as during a power outage.

First, FIG. 1 shows a main circuit configuration diagram of a typical conventional AC electric vehicle. In Fig. 1, the high voltage supplied through the pantograph l is stepped down to an appropriate voltage by a transformer.
rectifier 3. Thyristors Ja, 7b are connected to the rectifier 3 so that regenerative braking can be applied.
, 3c and 3d K.

A motor consisting of an armature and a field winding B is connected to the output side of the rectifier 3 via a flat sliding axle φ. Normally, the thyristors 3a to 3d of the rectifier 3 are sequentially phase-controlled so that the current flowing through the motor has a constant value. Therefore, a current detector 7 for detecting the motor current Id is connected in series with the motor, and a rectifier 3
An ignition signal G3 is applied to each of Sai 1 Nostars 3a to 3d.
A current controller 9 is provided to provide a(・shiG3(1) (dotted line arrow shown in FIG. A synchronous power supply g is connected between the terminals 9 and 9. Also, the main controller 10 instructs the notch signal and the current limit value, and is also connected to the current controller 7. ,
FIG. 2 shows waveforms at various parts in FIG. 1 when normal phase accumulation control is being performed. In FIG. 2, ES is the AC voltage of the secondary winding of the transformer, G3. to G3d are thyristors 3a to 3d constituting the rectifier 3, respectively.
ignition signal is shown. Furthermore, Ed is the output voltage of the rectifier 3, that is, the voltage applied to the motor, Id is the current flowing to the motor, and s is the AC If of the λ secondary winding of the transformer λ.
Show flow. Also, time T/ and TJ are 3 of the transformer.
This is the time when the direction of the frost 7 pressure on the secondary side changes; at time TI, the ignition signals G3o and G3a switch, and at time T3, the ignition signal G3 (1 and 031) switches.

Further, one time T2 is the time when the firing signals Gjb and G3d switch, and the time TF is the time when the firing signals G3a and G3o switch.

Next, the operation will be explained using the first and second parts.

First, it is assumed that the transformer λ AC voltage Es is applied at the rate shown in FIG. 1 from time TI to time 'rx. Then, at one time T/, ignition signals G3a, (), and yb are applied, which turns Cyrisks 3a and 3b on, forming a circuit of 3a→3b→9−)S→ru→7→3a. be done. At this time, the voltage Ed applied to the motor is zero. Next, time Tλ which is the point of control angle α from time Tl
Then, the ignition signal G, 7b is cut off, and instead, G3 (1 is entered,
Since the commutation action is performed from thyristor 3b to 3d, Ko→3d→G→S-+6→7→,? A −+ 2 circuit is formed and voltage Ed is applied to the motor. Next, at time T3, the polarity of the AC voltage gs is reversed. Then, the ignition signal G3d is cut off and G and 7b are turned on instead, and the commutation action from thyristor 3d to 3b is performed, so 3a → 3b → G → 5 → 6 →
A circuit 7→3a is formed, and the voltage Ed applied to the motor becomes zero. Then, at time T, the ignition signal Gja is cut off and G3o is turned on instead, and the commutation action is performed from the thyristor 3a to 30, so that; → 3b → q → S → 6 → 7 → Jc-
+ circuit is formed, and the applied voltage Ed changes from time Tj to T
It is applied in the same direction as the period J, and the same operation is repeated thereafter.

In other words, the operation is the same as that of a mixed bridge composed of a thyristor and a diode. Further, the current Id flowing through the motor at this time is smoothed to 5 by the smoothing coiler as shown by Id in FIG.

By the way, in the case of AC feeding, since the voltage and phase of each substation are different, so-called parallel feeding, in which power is fed from two or more 7# power stations to the same IC1 overhead line, is not possible, so it is not possible to perform so-called parallel feeding. A voltage-free section, sometimes called a sexy circle, is provided in between. In these types of places, there is no commutation voltage applied to the thyristor, so commutation is no longer possible.
Only normal phase control can be performed. Therefore, the third (a)
) The figure shows the waveforms of various parts when the overhead wire becomes unpressurized during phase control. In FIG. 3(a), time TI
At a time TJ' at a point of 91 control angle αl from k), the frame a! Assume that the voltage disappears, and as a result, the AC type output E8 on the secondary side of the transformer U becomes zero. Then, at the same time, the synchronous power supply g and, by extension, the current controller w are turned off, so that each of the gent signals is also turned off, and phase control becomes impossible thereafter. At time T, 7, when the AC ■ and the pressure E8 are reversed, the commutation action from Sai risk 3d to 3b'' is performed, and Sai 1j Sui...?a and -117□
, l ll star,? b, j and the motor current d continues, but in the non-pressurized state, the cyrisk 3b does not become a conductive state, so the motor m DC Id changes from 3a to the motor as shown by the broken line in Fig. 3(b). →Flows through 3d. In other words, a synchronous power supply t is used to synchronize the phase control of the thyristor with the overhead line voltage, but since the voltage applied to this synchronous voltage γ also disappears at the control angle α/that is, at time TJ', the thyristor is subsequently Firing signal GJa to l) J, 1
cannot occur. Therefore, when a current Id (same as d) as shown in Fig. 3(b) flows, DC biased magnetization is applied to the transformer, and when the overhead wire is repressurized after passing through Saekung Yong, the transformer 2. A large rush current will flow through the device, activating the protective device or damaging the equipment.

Because such a phenomenon occurs, conventionally, the driver sets the main controller's 7 sochi in advance before each section.
It was passing through with the main circuit open. In addition, this problem occurred not only at the alternating sections but also during a power outage in the overhead line, and the current that caused the DC bias current could continue for several seconds as if it was due to the f[f] of the smoothing 11 axle.

As described above, in the conventional method, the driver performs the notch-off in advance, which places a burden on the driver. There were some problems, such as the need to slow down near Sekunyong.

This invention was made in view of the problems of the conventional method, and as soon as the overhead line becomes unloaded, the current is forcibly brought into the current state, so that the direct current side E of the transformer does not occur. The purpose of this invention is to provide a control method for an AC electric vehicle.

Therefore, a configuration diagram of the main circuit based on the present invention is shown in Fig. 9. The difference from the conventional example shown in Fig. 1 in Fig. 9 is that in addition to the synchronous power supply, The main points are that the overhead wire voltage detector/l is directly connected to the pantograph/, and that the current controller/co's !1/m is the same as that of the conventional example shown in Fig. .

There''(゛、ノ↓3[21 shows the 11 construction of the Ttll iJI system, centered on Yoiri jK and jgoki l. 7 is the current detector, and 9 is the same. 1111 boxes, Sososhi”
L/0-Ogan 111] Imperial vessels, and these are the same as those in Figure 1. Also, l/ is an overhead wire voltage detector and /2 is a current controller. The current controller 12 includes a comparator/2 that compares the current limit value commanded from the master controller lθ etc. with the output of the current generator B7 that detects the current flowing through the motor.
a. Output of this comparator/2a and synchronous power supply? It is composed of a phase shifter/2b which determines the control phase angle of the thyristor using the output of the phase shifter/2b, and an ignition circuit talc which amplifies the output of the phase shifter/2b and provides an ignition signal to the thyristor of the rectifier 3. The output of the overhead line voltage detector // is.

Applied to ignition circuit /2C. Note that depending on the configuration of the control system, the output of the overhead line voltage detector ll may be given to the phase shifter /:lb. Further, FIG. 6(a) shows waveforms of various parts of the apparatus shown in FIG. 9 when the overhead wire becomes unpressurized during phase control. The symbols in FIG. 6(a) are the same as in FIG. 3(a).

Therefore, the operation when the overhead wire is not pressurized will be explained. In FIG. 6(a), at time TJ', which is a point at a control angle α/ from time Tt, the overhead wire becomes unpressurized, and the AC voltage Es on the primary side of transformer λ becomes zero. Therefore, the overhead wire voltage detector // sends a signal to the current controller /, 2's ignition circuit /, 2c to inform that the overhead wire is no longer pressurized, and this signal causes the ignition circuit /2c to switch to the rectifier 3's ignition circuit /, 2c. An ignition signal is given to all the scissors 3a to 3d. Therefore, all thyristors 3a are not? d becomes a conductive state, and the motor current Id flows as shown in FIG. 6(b). A tributary current flows to the transformer when the thyristor becomes conductive. becomes zero and does not give any direct current bias. Then, when the overhead line voltage returns after passing through several sections, normal phase control resumes. Incidentally, the ignition signal for the thyristor is supplied from a battery (tC in the figure) so that it can be generated in a state where the overhead wire is not pressurized. Further, the detection level of the overhead line voltage detector // is determined in consideration of the fluctuation range of the overhead line voltage, etc.

In the above-described embodiment, when the overhead line voltage disappears, all the q thyristors 3a to 3d are turned on to conduct electricity, but only the thyristors 3a and 3b may be turned on. In other words, this means that even if only one arm of the bridge is allowed to flow, the same effect can be obtained. For example, if the rectifier 3 in FIG. 9 is a mixed bridge composed of a thyristor and a diode, and the thyristors 3a and 3b are composed of diodes, when the firing signal of the thyristor 3c or thyristor 3d disappears, Since the current naturally transfers to the diode side, there is no direct current bias applied to the transformer, so there is no problem.

In addition, the overhead line voltage detector is used not only on the primary side of the transformer, but also on the primary side of the transformer.
It is also possible to use a detector for other windings such as the secondary side.

Furthermore, this method can be easily applied even when the secondary winding of the transformer is multi-divided and multiple stages of rectifiers are connected in cascade.

As described above, by applying the control method according to the present invention, in the unpressurized section of the overhead wire, as in the conventional case,
It is no longer necessary to turn off the notch of the main controller, which facilitates driving operation and improves running speed.

[Brief explanation of drawings]

Figure 1 is a configuration diagram of the main circuit of a typical conventional AC train.
Figure 2 is a waveform diagram of each part in the circuit of Figure 1, Figure 3(a) is a waveform diagram of each part when the overhead wire is not pressurized during phase control, and Figure 3(b) is a waveform diagram of each part of the overhead wire. Figure q is a block diagram of the main circuit based on this invention, Figure S is a block diagram of the control system of the main circuit, and Figure A is a diagram of the current path in the rectifier when no pressure is applied. A waveform diagram of each part when the overhead wire becomes non-pressurized during control, and Figure 6(b) is a current path diagram in the rectifier when the overhead wire becomes non-pressurized. 3. Rectifier, 3 a, Jb, ?c and 7d--thyristor, 7--current detector, ?--synchronous power supply, 10--master controller, /...overhead line voltage detector, /co--current controller , /2e1... comparator, /, 2b
・・Phase shifter, /C・・Ignition circuit. In addition, in FIG. 1, the same reference numerals indicate the same or equivalent parts. Agent Shin Kuzuno −

Claims (1)

[Claims] An AC electric car equipped with a rectifier configured with a pure bridge of Cyrisk, characterized in that the thyristor is forced into a conducting state when the AC electric car passes through an unpressurized section of an overhead wire or during a power outage. A control method for an AC electric car.