JPS5917867A - Controlling method and device for chopper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chopper control method using a thyristor chopper capable of regenerative control, and a device used to carry out the method.The present invention can be used, for example, as a control device for a separately excited DC motor. In particular, it is used in a control device that performs boost operation without switching the main circuit and enables regenerative braking.

Conventionally, in an electric vehicle using a direct current passive motor as a prime mover, when the back electromotive force Er is smaller than the terminal voltage ES of the battery 11 at a speed below the base speed, the chopper is turned on to raise the armature current ia. , and then turns off, and due to the inductance L of the brake pedal, E s = E r
+L-dia/dt, and regenerative braking was performed. For this reason, contacts were needed to switch the main circuit, and a large number of switches were needed to switch the main circuit without contact.

Therefore, it is an object of the present invention to provide a new chopper control method and apparatus capable of controlling regeneration, which allows for a circuit configuration that does not require the use of a large number of silicon risks.

The present invention will be explained below.

First, the principle of the present invention will be explained using FIG.

In order to eliminate the above-mentioned drawbacks, the present invention focuses on the commutating capacitor 21 conventionally used for power control, and attempts to boost the battery voltage Es- (back electromotive force 13r + capacitor voltage ec). It is. That is, in FIG. 1, the switch 4-24 is pushed down to charge the capacitor J 21 to the polarity shown, and then pushed back up to perform regeneration.

An embodiment of the present invention will be described below. This embodiment is an electric vehicle control device, and in FIG. 2, reference numeral 47 is a cylindrical tip T1 collar used for both power and regeneration.

The operation during regeneration can be easily analogized, so to briefly explain the operation during regeneration, it is equivalent to operating the switch 24 up and down in Fig. 1 by alternately triggering the thyristors 39 and 33. . The voltage and current waveforms of the capacitor 21 at this time are shown at 101.102a and 102b in FIG.
Further, the current waveform of the armature 15 is shown at 103.

One embodiment will be described in detail below with reference to FIGS. 2 to 5.

Reference numeral 11 denotes a DC power supply composed of a lead-acid battery or the like, and is supplied with power by a thyristor chopper 47 to an armature 15 of a separately excited DC motor 17 serving as a load via a smoothing reactor I4. The thyristor 46 and the thyristor chopper 47 are
This is for flowing a circulating current (freewheeling current) when the circuit is FF. Note that 16 is an excitation winding of a DC separately excited motor 17, to which an excitation current is supplied by a drive circuit (not shown). The thyristor chopper 47 includes the main thyristor 32, the reversing thyristor 33, and the commutation thyristor 4.
4. A series arc-extinguishing type repulsion pulse thyristor chopper composed of a commutation capacitor 21 and a commutation reactor 35. Furthermore, the chopper 47 is used for back electromotive force load or for ensuring recommutation capability after commutation failure. It includes a charging reactor 38, a charging thyristor 39, and a diode 31 that enables high-speed operation and allows regenerative current to flow, which constitutes an auxiliary charging circuit.

In FIG. 2, first, the operation when moving (when the FTI motor 17 is rotationally driven) will be explained. First, the thyristor 39 is turned on and the commutating capacitor 21 is charged to the illustrated polarity. Next, the main thyristor 32 is ignited and voltage is applied to the armature 15. In order to turn off the main thyristor 32, the thyristor 33 is turned on to reverse the polarity of the capacitor 21, and then the thyristor 44 is turned on to complete the commutation operation. and,
At the same time, the thyristor 46 may be turned on to function as a freewheel diode. Therefore, all the thyristors are fired in their respective phases during the power cycle.

Next, the operation during regenerative braking will be explained based on FIGS. 2 and 3. When the thyristor 39 is triggered when the capacitor 21 has no charge, the power supply 11 and the capacitor 21
, reactors 35, 38, and thyristor 39 constitute a series resonant circuit, and capacitor 21 is charged to a maximum value of approximately 2Es with the polarity shown in the drawing, and thyristor 39 is turned off. When the thyristor 33 is tripped in this state, the armature 15
And the voltage applied to the reactor 14 is the capacitor 21
voltage (2Es) - battery voltage (Es) = Es, and the armature current ia in the direction shown is thyristor 33 - 'J accelerator 35 - capacitor 21 - battery 11 -> armature 15
- Flows through the smooth sliding axle 14 and is regenerated by the power source 11.

This armature current ia, that is, the regenerative current ia is the capacitor 2
Voltage ec of 1 (ec is instantaneous value) increases from 2Es (maximum value) until it drops to battery voltage - back electromotive force of armature - (Es - Er), then decreases and finally reaches ec#o. Become.

In other words, when the capacitor 21 is charged to 2Ec, the thyristor 33 is turned on as described above, so the back electromotive force Er generated in the armature 15 at that time and the voltage 2Es of the capacitor 2I are added together to charge the battery 11. However, the capacitor 21 is charged with the charging current i.
Since the voltage a is borne by the capacitor's own discharge, the voltage across the capacitor 21 drops after the armature current ia begins to flow. On the other hand, the armature current ia, that is, the battery charging current ia, does not flow suddenly due to the inductance of the circuit, and gradually increases as shown in Fig. 3 te+, but the residual voltage ec of the capacitor 21 + the counter electromotive force at that time) When Er is equal to the battery voltage Es, that is, ec+Er=Es
, ', (ec=Es-Er), the armature current ia will stop flowing.

However, ia does not suddenly become O, but gradually becomes smaller as shown in FIG. 3 (el) due to the inductance of the circuit.

That is, the regenerative current ia is generated when the voltage of the capacitor 21 is ec.
=2Es to e c+==lEs−r! , r (that is, ec+Er=Es), and then decreases. Moreover, finally the residual voltage ec' of the capacitor 21
;It becomes 0.

After becoming e c#0, E r passes through diode 31.
+ Voltage of L-dia/dt (Er: back electromotive force.

The battery is charged by ia (armature current).

Note that these operating waveforms are shown in FIG.

102a in FIG. 3 is a capacitor charging current, and 102b is a capacitor discharging current. The trigger timing of thyristors 39 and 33, that is, the timing to turn them on, is set to 139, 133.
The trigger pulse waveform is shown below.

101 is a voltage waveform of the capacitor 21.

FIG. 4 shows a trigger signal generation circuit for supplying a signal during regenerative braking to the control device of the present invention.

71 is a variable resistor linked to the brake pedal etc.
Generates a voltage proportional to the amount of depression of the brake pedal. Operational amplifier 72. A voltage follower circuit is constituted by the resistor 73, and supplies a voltage proportional to the amount of depression of the brake pedal to a V-F converter described below.

V-F converter has resistance 74, 77.79.80°81.8
2,86.8? , 89.94, capacitor 76.83,
It is composed of transistors 78 and 88, a diode 85, operational amplifiers 75 and 84, a NAND gate 90, and an inverter 91. Resistor 92°93.95, transistor 98
, a pulse amplifier is constituted by a pulse transformer 97, diodes 96, 99, and a =1 capacitor 55, and O^°,
One child 1 and 2 each have a charging thyristor 39 (ff1
It is connected to the gate and cathode in Figure 2).

Similarly, a pulse amplifier is configured by resistors 64, 65, transistor 68, pulse transformer 67, diode 6 (i, 69, and capacitor 56), and terminals 3, 4 are connected to the gate and cathode of regenerative thyristor 33 (Fig. 2), respectively. 61 is a negative edge trigger type monostable multi-by-break, which causes thyristor 3!
) until the charging of the capacitor 21 is completed. 62 is also a negative edge trigger type monostable multivibrator, which determines during the trigger pulse of the thyristor 33. 63 is a positive edge trigger type monostable multivibrator, which constitutes a time-limited circuit until the voltage of the capacitor 21 becomes O after triggering the regenerative thyristor 33 and the regenerative current starts flowing through the diode 31. There is.

FIG. 5 (al to (fl) indicate voltage waveforms Va to Vf at each point a to f shown in FIG. 4.

Next, the function of Cyrisk 46 will be described.

When the thyristor 33 is turned on, the voltage of the capacitor is charged to 2Es in the polarity shown in FIG. Therefore, at the moment when the thyristor 33 is turned on, between 11 and 22 -
Es is applied, and this voltage -Es is in the direction of addition to the back electromotive force Er of the motor. Therefore, a voltage of (Er+Es) is applied to the reactor I/L 14,
The regenerative current will rise rapidly (di/dt=(
1/L)X (Er+Es)). Therefore, thyristor 4
If 6 is a diode, the above -Es is shorted, so the rise of the current in the reactor 14 is d1/dt
= 1 ・E r /L and becomes smaller.

Therefore, it turns out that it is better to use the thyristor 46.

Note that if a freewheeling diode is used in place of the Cyrisk 4G as in the past, the ratio of the regenerative current to the switching frequency will decrease, but regeneration is basically possible with the diode as well. In particular, when the reactor 38 is simplified to a resistor, a diode is sufficient. but,
It is somewhat impossible to secure braking force equivalent to engine braking in electric cars. Note that the firing timing of this thyristor 46 may be set as follows. In other words, it is sufficient to trigger the trigger at the same time as turning off the pulse generator 47 at the time of movement, and the trigger may be triggered at the same time as the thyristor 44 (the pulse can be shared). There is no need for any force during regeneration.

Therefore, thyristor 46 is not an essential component of the method of the invention.

Next, the necessity of the reactor 14 will be described.

In conclusion, there is no reactor 14 (but regeneration is possible. This reactor I4 is simply to reduce ripples when the motor is running and braking, and even if omitted, the effect of the present invention will be reduced (:i Also, armature 15
Since this originally has a minute inductance, the actuator 4 used as a substitute is often omitted in electric vehicles.

However, in the case of a train, a reactor 14 is provided as a countermeasure against electromagnetic interference caused by ripples in the overhead line current.

FIG. 6 shows a main circuit diagram of a second embodiment in which the present invention is implemented in a parallel arc-extinguishing type repulsion pulse thyristoronper. The main thyristor 32, the inversion thyristor 33, the commutation thyristor 44, the commutation capacitor 21, and the commutation reactor 35 constitute a repulsion pulse thyristor, and the reactor 38 and the thyristor 39 constitute an auxiliary charging circuit. Note that 51 is a regenerative scissor.

As described above, in the method of the present invention, the commutation capacitor of the thyristor and bar having an auxiliary charging circuit for driving a back electromotive force load such as a DC passive motor is used as a step-up capacitor for regenerative control. Since it is also used as a capacitor, it has the effect of being able to switch power and regeneration control at high speed without contact with a very simple main circuit.

[Brief explanation of the drawing]

FIG. 1 is a principle diagram for explaining the principle of the method of the present invention;
Fig. 2 is an electrical circuit diagram of the main circuit of an electric vehicle using an embodiment of the method of the present invention, Fig. ff13 is a voltage or current waveform diagram of each circuit shown in Fig. 2, and Fig. 4 is a diagram of the circuit shown in Fig. 2. FIG. 5 is an electric circuit diagram showing a part of the control amount +78 to be controlled, FIG. 5 is a waveform diagram of each part of the 1111 people shown in FIG. 4, and FIG. 6 is an electric circuit diagram showing another embodiment of the present invention. 17...For example, the flJr machine as a load, 11...DC power supply, 47...Sirisk diconoper, 32...Main thyristor, 21...Commuting capacitor, 35...Commuting reactor , 33...Syrisk for reversal, 44...
・Commutation sirisk, (21, 25)...Series circuit, 3
B... Charging reactor, 39... Charging thyristor, 33... The reversing thyristor that also serves as a regeneration thyristor, 51... Regeneration thyristor. Representative Patent Attorney Takashi Okabe

Claims (1)

[Claims] 1. Commutation capacitor (21) and commutation reactor (3)
A thyristor chopper (47) constitutes a forced commutation circuit by a resonant circuit using 5) and has an auxiliary charging circuit (38, 39) to supply power to a load (17) that generates a back electromotive force.
A chopper control device comprising: a chopper control method, characterized in that the commutation capacitor (21) is used as a boost capacitor during regeneration control. 2. A load (17) that generates a back electromotive force, and a load (17) that generates a back electromotive force.
) and the DC power supply (11), and the load (17
) for chopping control of the voltage applied to the thyristor chopper (47).
) is the main thyristor (32) and the main thyristor (32).
A commutating capacitor (21) and a commutating reactor (35) connected in parallel to the commutating capacitor (
It consists of an inverting thyristor (33) that reverses the polarity of the thyristor (21), and a commutating thyristor (44) that commutates the main thyristor (32), and a commutating capacitor (2) of the thyristor collar (47).
1) and a commutation reactor (35) in series circuit (21, 3)
5) is connected in series with the DC power source (11), and the charging reactor (38) and the charging cyrisk (39).
are connected in series to the DC power supply (11) and the series circuit (
21, 35), and the commutating capacitor (
21), a commutation reactor (35), the load (17), and the DC power source (11) are provided with a regenerative thyristor (33, 51) forming a regenerative circuit so that the charging thyristor ( 39) is turned on to accumulate a high voltage in the commutation capacitor (21), and then the regeneration cyrisk (33, 51) is turned on. 3. In the device according to claim 2, a thyristor (46) is connected to the load (14), and the thyristor (46) causes a freewheeling current of the load to flow.
46) is the chopper (
A device characterized in that it is fired in synchronization with the commutation of item 47) and is not fired during regeneration control.