JP5427403B2 - Battery charger - Google Patents

Description

  The present invention relates to a three-phase noiseless short type battery charger using a permanent magnet type three-phase AC generator.

The conventional battery charging system for motorcycles is mainly a thyristor short type Reg / Rec using a three-phase AC generator, and its circuit configuration is as shown in FIG. 6 (see, for example, Patent Document 1). .
At the time of battery charging, the current of the three-phase AC generator 1 is rectified by a rectifier circuit including diodes D1 to D6 and charged to the battery B.
When the battery B is fully charged, the controller C detects the battery voltage, and the thyristor groups S1 to S3 connected in parallel with the opposite polarities of the diodes D4 to D6 are connected to the resistors R1, R2, and R3, respectively. Is turned on by passing a drive current through the ACG, and the ACG is short-circuited to the negative terminal of the battery to control charging.
That is, each phase of the three-phase AC generator is short-circuited by the route of the U phase-S1-D5-V phase, the V phase-S2-D6-W phase, and the W phase-S3-D4-U phase. As described above, when the controller C detects that the battery is fully charged, the controller C controls the charging current to the battery by short-circuiting the output terminal of the three-phase AC generator.
Japanese Patent Laid-Open No. 10-70851

In the above-described conventional example, when the charging is controlled by short-circuiting the windings of the three-phase AC generator, the controller C controls the thyristor provided corresponding to each of the three phases as described above. Thus, control is performed so that the charging current does not flow to the battery.
However, according to the load (battery) state and the rotation speed of the three-phase AC generator, in the control of the AC current due to the short circuit of the thyristor in this full charge, the current flowing through each of the three thyristors is uniform, that is, the same phase. In some cases, it does not flow at the number of times and concentrates on a specific phase.
Since a three-phase AC generator is formed by winding a winding around an iron core for each phase, as described above, if a current flows concentrated on a specific phase, the amount of current flowing in the winding for each phase is insignificant. It becomes equilibrium. For this reason, when the degree of heat generation of each of the windings is greatly different, the degree of deterioration between the windings varies.
Therefore, in the conventional example, when the winding of any phase of the three-phase AC generator is further deteriorated with respect to the other windings, the amount of current flowing between the windings further varies. As a result, there is a drawback that the life of the three-phase AC generator is shortened.

  The present invention has been made in view of such circumstances, and when the battery is fully charged, when the output of the three-phase AC generator is short-circuited by the thyristor, the current that is short-circuited and the current that flows between the phases is equal. Battery that extends the life of the three-phase AC generator by balancing the winding current of the three-phase AC generator between phases and averaging the life of the winding by conducting on / off control of the thyristor so as to conduct at An object is to provide a charging device.

The battery charging device of the present invention includes a three-phase AC generator that supplies an AC voltage for battery charging, a diode bridge that rectifies the AC voltage of each phase in the three-phase AC generator, and the three-phase AC generator. Thyristor connected to the output terminal of each phase and short-circuiting the output terminal, and detecting whether or not the charging voltage of the battery to be charged exceeds a preset threshold and outputting a detection signal and parts, when the detection signal is inputted, the thyristor firing start timing storage unit for outputting a thyristor-on signal for turning on the respective thyristors, on the basis of the thyristor on-signal, the thyristor AC of the phase A thyristor-on signal output unit that is turned on in the order of voltage phases.

Battery charging apparatus of the present invention, prior Symbol further includes an AC polarity detection unit for detecting the polarity of the alternating current each output of each phase of the three-phase AC generator, the thyristor ON signal output unit, the AC polarity detection The control signal for turning on the thyristor corresponding to the phase is output in synchronization with the polarity information of each phase output from the unit.

  The battery charging device of the present invention is characterized in that the thyristor ignition start timing storage unit outputs the thyristor ON signal in synchronization with any one of the phases.

  As described above, according to the battery charger of the present invention, the thyristor that starts on / off in advance in the order of the phase of the AC voltage output from the three-phase AC generator is stored in the thyristor ignition start timing storage unit. The thyristor conduction ratio corresponding to the phase of each AC voltage generated by the three-phase AC generator in order to sequentially control the conduction of the thyristor in the order of the phase from the thyristor corresponding to the phase of the stored AC voltage. Can be made uniform, and the heat generated in the windings of each layer can be averaged to equalize the deterioration, thereby extending the life of the three-phase AC generator.

Hereinafter, a battery charger according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of the battery charging device according to the embodiment.
In FIG. 1, the same parts as those of the conventional apparatus shown in FIG. The device shown in FIG. 1 is different from the conventional device in that the configuration of the thyristor control signal generating unit 1 that generates a thyristor control signal includes an AC polarity detecting unit 11, a battery voltage detecting unit 12, and a thyristor firing start timing storage unit. 13, a thyristor ON signal output unit 14 and a control circuit drive power generation unit 15 are provided.
In FIG. 1, a three-phase AC generator ACG outputs AC currents of phases U, V, and W as output AC currents AC1, AC2, and AC3 from output terminals TAC1, TAC2, and TAC3, respectively.

A rectifier circuit (diode bridge) 2 including diodes D1, D2, D3, D4, D5, and D6 rectifies the alternating current output from each of the output terminals TAC1, TAC2, and TAC3, and causes a charging current to flow to the battery B. The battery B is charged by this charging current. Here, the anode of the diode D1 is connected to the output terminal TAC1, the anode of the diode D2 is connected to the output terminal ATC2, and the anode of the diode D3 is connected to the output terminal TAC3. The cathodes of D1, D2 and D3 are connected to the positive terminal of the battery.
The cathode of the diode D4 is connected to the output terminal TAC1, the cathode of the diode D5 is connected to the output terminal TAC2, the cathode of the diode D6 is connected to the output terminal TAC3, and the anodes of the diodes D4, D5, and D6 are connected to the battery − Connected to the terminal.

When the thyristor S1 has an anode connected to the output terminal TAC1, a cathode connected to the negative terminal of the battery B, a gate connected to the output terminal TO1 of the thyristor control unit 14, and a drive signal for firing the gate is input. The output terminal TAC1 is short-circuited to the negative terminal of the battery B.
When the thyristor S2 has an anode connected to the output terminal TAC2, a cathode connected to the negative terminal of the battery B, a gate connected to the output terminal TO2 of the thyristor control unit 14, and a drive signal for firing the gate is input. The output terminal TAC2 is short-circuited to the negative terminal of the battery B.
When the thyristor S3 has an anode connected to the output terminal TAC3, a cathode connected to the negative terminal of the battery B, a gate connected to the output terminal TO3 of the thyristor control unit 14, and a drive signal for firing the gate is input. The output terminal TAC3 is short-circuited to the negative terminal of the battery B.

The AC polarity detection unit 11 inputs any two phases of the AC currents AC1, AC2, and AC3 of each phase from the output terminals TAC1, TAC2, and TAC3 of the three-phase AC generator ACG, and the AC of the two respective phases. The polarity of the current waveform is detected, and the detection result is output to the thyristor firing start timing storage unit 13 as a signal Ed indicating the timing of the phase change of the two AC signals.
The battery voltage detection unit 12 measures the voltage between the + terminal and the − terminal of the battery B, that is, the inter-terminal voltage as the charging voltage, and the inter-terminal voltage is set to a preset threshold voltage (the charging state of the battery B). Threshold voltage for detecting whether or not the battery is fully charged) is detected. A charge / short-circuit flag signal of “L” level when full charge is exceeded and “H” level when charge is required Is output.

  The thyristor ignition start timing storage unit 13 receives the phase information of the AC voltage output from the three-phase AC generator ACG as the signal Ed (Ed21 to be described later), and the thyristor on timing corresponding to the timing of the signal Ed. Output a signal. Therefore, this thyristor ON signal includes information on the phase of the AC voltage corresponding to the thyristor that starts firing as the output timing.

When the thyristor-on signal output unit 14 receives the thyristor-on signal, which is thyristor identification information, the thyristor-on signal output unit 14 outputs a gate signal to the thyristor (any one of the thyristors S1 to S3) in the inputted phase. Thereafter, gate signals are sequentially output to the thyristors in the order of the phases, and each is ignited and turned on.
The control circuit drive power supply generation unit 15 drives the components of the AC polarity detection unit 11, the battery voltage detection circuit 12, the thyristor firing start timing storage unit 13, and the thyristor on signal output unit 14 from the output voltage of the battery B. A voltage is generated and supplied to each unit.

Next, a configuration example of the AC polarity detection unit 11 will be described in detail with reference to FIG. The PNP transistor Tr1 has an emitter connected to the terminal T1, a base connected to its own emitter via a resistor R11, and a base connected to the anode of the diode DD1 via a resistor R12. The diode DD1 has a cathode connected to the terminal T2. The terminal T1 is connected to the ACG output terminal TAC2, and the terminal T2 is connected to the ACG output terminal TAC1.
The collector of the transistor Tr1 is connected to the base of the NPN transistor Tr2 via the resistor R13. The transistor Tr2 has an emitter connected to its base via a resistor R14, a collector connected to the + terminal of the battery B via a resistor R15, and outputs a signal Ed21 from the collector.

In this embodiment, it is only necessary to detect the phase of any one of the phases. Therefore, the thyristor is driven at a phase where the AC signal AC2 is higher than the AC signal AC1 by the phase voltage between the AC signal AC2 and the AC signal AC1. It is detected as a timing for determining whether or not.
That is, when the voltage of the AC signal AC2 becomes higher than the voltage of the AC signal AC1, a current flows from the base of the transistor Tr1 via the diode, and the transistor Tr1 is turned on. When the transistor Tr1 is turned on, a current flows into the base of the transistor Tr2, the transistor Tr2 is turned on, and the voltage of the signal Ed21 changes from the “H” level of the battery voltage to the “L” level of the ground potential.

On the other hand, when the voltage of the AC signal AC1 becomes higher than the voltage of the AC signal AC2, or when the voltage of the AC signal AC2 and the voltage of the AC signal AC1 are the same, no current flows from the base of the transistor Tr1 via the diode, The transistor Tr1 is turned off. When the transistor Tr1 is turned off, no current flows into the base of the transistor Tr2, the transistor Tr2 is turned off, and the voltage changes from the “L” level of the ground potential of the signal Ed21 to the “H” level of the battery voltage.
As described above, the signal Ed21 changes from the “H” level to the “L” level at the timing when the voltage of the AC signal AC2 becomes higher than the voltage of the AC signal AC1.

Next, a configuration example of the thyristor firing start timing storage unit 13 will be described in detail with reference to FIG.
The thyristor firing start timing storage unit 13 is configured by a flip-flop FF1, for example, as shown in FIG.
In the flip-flop FF1, the charge / short-circuit flag signal is input from the battery voltage detection circuit 12 to the data input terminal D, the signal Ed21 output from the AC polarity detection unit 11 is input to the clock terminal CKB, and the thyristor ON is output from the output terminal Q. Output a signal. Here, as described above, when the battery voltage of the battery B is lower than the preset charging voltage, the charge / short-circuit flag signal is output from the battery voltage detection unit 12 at the “H” level, and the battery When the battery voltage of B is equal to or higher than a preset charging voltage, it is output from the battery voltage detection unit 12 at the “L” level.

  That is, the flip-flop FF1 is input to the data input terminal D when the signal Ed21 changes from “H” level to “L” level, that is, when the falling edge of the signal Ed21 is input to the clock terminal CKB. The level of the charge / short-circuit flag signal is latched, and the latched level is output from the output terminal Q. Here, when the “L” level charge / short-circuit flag signal is input to the data input terminal D, the flip-flop FF1 outputs the thyristor ON signal (“L” level signal) at the falling edge of the signal Ed21. Output.

Next, a configuration example of the thyristor ON signal output unit 14 will be described in detail with reference to FIG. The circuit shown in FIG. 4 is provided for each of the thyristors S1, S2, and S3, and individually controls the driving of the thyristors S1, S2, and S3. Hereinafter, one circuit is shown, and the gates of thyristors S1, S2, and S3 are assumed to be Sn (n = 1, 2, 3), and the ACG output terminal is assumed to be TACn (n = 1, 2, 3). .
The PNP transistor Tr3 has an emitter connected to the terminal T3, a base connected to its own emitter via the resistor R21, and a base connected to the anode of the diode DD2 via the resistor R22. The diode DD2 has a cathode connected to the terminal T4. Terminal T3 is connected to the positive terminal of battery B, and terminal T4 is connected to output terminal TACn of ACG.

The transistor Tr3 has a collector connected to the emitter of the PNP transistor Tr4.
The transistor Tr4 has an emitter connected to its base via a resistor R23, a collector connected to the gate of the thyristor Sn via a terminal T5, and a base connected to the output terminal Q of the flip-flop FF1 via a resistor R24. Has been.
In the circuit of FIG. 4, the thyristor ON signal is input at the “L” level (the transistor Tr4 is in the ON state), and the AC signal ACn (n = 1, 2, 3) is at the “L (− polarity)” level ( When the transistor Tr3 is turned on, a drive signal for the thyristor is output to the gate of the thyristor Sn.

The operation of the battery charging circuit configured as described above will be described with reference to the waveform diagram shown in FIG.
In this figure, AC1-E, AC2-E, and AC3-E respectively indicate the polarities of the U-phase, V-phase, and W-phase AC voltage waveforms output from the ACG.
AC1-E, AC2-E, and AC3-E each have a U-phase waveform output from the diode D1, a V-phase waveform output from the diode D2, and a W-phase waveform output from the diode D3. Show. Here, when the thyristor Sn (n = 1, 2, 3) is in an off state, the AC voltage waveform output from the diode Dn (n = 1, 2, 3) is a waveform of the voltage VH as a peak value. On the other hand, when the thyristor n is in the ON state, the AC voltage waveform output from the diode n becomes a waveform of the voltage VL as a peak value. When the peak value of the AC voltage waveform is the voltage VH, the battery B is charged, and when the peak value is the voltage VL, the battery B is not charged.

In the present embodiment, the thyristor ON signal is output based on the voltage level of the charge / short-circuit flag signal at the rising etch timing of the signal Ed21, and as shown below, the battery B is fully charged. When the short-circuit state is established, the thyristor Sn is turned on starting from the thyristor S1, sequentially turned on with the thyristor S2 and the thyristor S3, and the three-phase terminals TAC1, TAC2, and TAC3 of U phase, V phase, and W phase are collectively connected. To ground and stop charging.
Similarly, when the battery B needs to be charged, the thyristor Sn is turned off from the thyristor S1 and sequentially turned off from the thyristor S2 and the thyristor S3. The terminals TAC1, TAC2, and TAC3 are not collectively grounded, and charging the battery B is started.

  In the following description, battery B is in a charged state at a time prior to time t1. That is, the battery voltage detector 12 detects that the battery B does not exceed the charging voltage (has not reached the target value), sets the charging / short-circuit flag signal to the “H” level, and the thyristor ignition start timing storage unit 13 latches the “H” level of the charge / short-circuit flag signal at the timing when the signal Ed21 output from the AC polarity detection circuit 11 falls from the “H” level to the “L” level, and “H” from the output terminal Q. A level signal is output, and an “L” level thyristor ON signal is not always output.

  At time t1, battery voltage detection unit 12 detects that battery B has exceeded the charging voltage, and changes the charging / short-circuit flag signal from the “H” level to the “L” level.

At time t2, when the signal Ed21 output from the AC polarity detection circuit 11 falls from the “H” level to the “L” level, the thyristor firing start timing storage unit 13 sets the charge / short-circuit flag signal to the “L” level. Therefore, the “L” level thyristor ON signal is output to the thyristor ON signal output unit 14.
The thyristor-on signal output unit 14 receives the thyristor-on signal and outputs the drive signal to the gate of the thyristor S1 because the AC signal AC1 is at the “L” level.
Similarly, the thyristor ON signal output unit 14 outputs a drive signal to the gate of the thyristor S3 because the thyristor ON signal is input and the AC signal AC3 is at the “L” level.
As a result, the thyristors S1 and S3 are turned on, so that the output terminals TAC1 and TAC3 of the ACG are grounded.

  At time t3, the AC signal AC3 output from the output terminal TAC3 of the ACG actually outputs a + polarity waveform with the voltage VH as a peak, but since the terminal TAC3 is grounded by the thyristor S3, the voltage It is clamped to VL (voltage drop in the forward direction of the thyristor).

At time t4, the thyristor ON signal output unit 14 receives the thyristor ON signal and the AC signal AC2 becomes “L” level, and therefore outputs a drive signal to the gate of the thyristor S2.
As a result, the thyristor S2 is turned on, so that the output terminal TAC2 of the ACG is grounded.

  At time t5, the AC signal AC1 output from the output terminal TAC1 of the generator ACG actually outputs a positive polarity waveform with the voltage VH as a peak, but the terminal TAC1 is grounded by the thyristor S1. And VL (voltage drop in the forward direction of the thyristor). Similarly, the AC signal AC2 also outputs a waveform having a polarity of + with a peak at the voltage VH. However, since the terminal TAC2 is grounded by the thyristor S2, the voltage VL (the forward drop of the thyristor) is output. Voltage).

  At time t6, the battery voltage detection unit 12 detects that the discharge of the battery B1 has progressed and the output voltage of the battery B1 has fallen below the charge voltage, and changes the charge / short-circuit flag signal from the “L” level to the “H” level. Change.

At time t7, the thyristor firing start timing storage unit 13 latches the charge / short-circuit flag signal at the “H” level at the falling edge of the signal Ed21, thereby changing the thyristor on signal from the “L” level to the “H” level. Change to level.
At this timing, the thyristor ON signal output unit 14 stops outputting the drive signal to the gates of the thyristors S1, S2, and S3.
Since the thyristors S1, S2, and S3 are no longer supplied with drive signals at their gates, the AC signals AC1, AC2, and AC3 from the generator ACG change from + to-polarity, so that they are sequentially turned on and off. To change.

At time t8, the AC signal AC3 output from the output terminal TAC3 of the generator ACG has a positive polarity waveform with the thyristor voltage VH as a peak.
Further, since the thyristor S3 is in the OFF state, the AC signal AC3 having the thyristor voltage VH as a peak is output from the diode D3 to the battery B.

At time t9, the AC signal AC1 output from the output terminal TAC1 of the generator ACG has a positive polarity waveform with the thyristor voltage VH as a peak.
Further, since the thyristor S1 is in the off state, the AC signal AC1 having the peak thyristor voltage VH is output from the diode D1 to the battery B.

At time t10, the AC signal AC2 output from the output terminal TAC2 of the generator ACG has a + polarity waveform with the thyristor voltage VH as a peak.
Further, since the thyristor S2 is in the off state, the AC signal AC2 having the peak thyristor voltage VH is output from the diode D2 to the battery B.
Therefore, from time t8, AC signal AC3 to AC signal AC1, AC signal AC2 and an AC signal having a peak thyristor voltage VH are sequentially supplied to battery B, and the charging process is started.

At time t11, the battery voltage detection unit 12 detects that the battery B has exceeded the charge voltage, and changes the charge / short-circuit flag signal from the “H” level to the “L” level.
The subsequent processing is the same as the processing at the times t2 to t8 already described.

  As described above, in the present embodiment, the signal Ed21 for detecting the phase of each AC signal output from the generator ACG is created by the AC signal AC1 and the AC signal AC2, and the signal E21 falls. A thyristor ON signal is generated from a charge / short-circuit flag signal corresponding to the charging voltage of battery B, and thyristors S3, S1, and S2 are turned on or off according to the thyristor on signal and each AC signal AC3, AC1, and AC2. Is controlling.

For this reason, in the present embodiment, the thyristors S1 and S2 are always sequentially started from the thyristor S3 by generating the thyristor ON signal for controlling the on / off of each thyristor in synchronization with the signal Ed21 generated from the AC signals S1 and S2. Can be controlled so that the thyristor S1 and the thyristor S2 are always turned off sequentially from the thyristor S3.
That is, in the present embodiment, the thyristors S1, S2 and S3 are always synchronized (as one processing terminal) to control the on state and the off state, so that the number of times all thyristors are turned on / off is the same, As in the conventional example, the number of times that any thyristor is turned on is not increased, the heat generation of the windings of each layer is averaged, and the deterioration is made uniform, so that the life of the three-phase AC generator is increased compared to the conventional example. It can be extended.

It is a block diagram which shows the structural example of the battery charging device by one Embodiment of this invention. It is a conceptual diagram which shows the circuit structural example of the alternating current polarity detection part 11 in FIG. FIG. 2 is a conceptual diagram illustrating a circuit configuration example of a thyristor firing start timing storage unit 13 in FIG. 1. It is a conceptual diagram which shows the circuit structural example of the thyristor ON signal output part 14 in FIG. It is a wave form diagram which shows the operation example of the battery charging device by one Embodiment of this invention. It is a block diagram which shows the structural example of the conventional battery charging device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 ... Rectifier circuit 11 ... AC polarity detection part 12 ... Battery voltage detection part 13 ... Thyristor ignition start timing memory | storage part 14 ... Thyristor ON signal output part 15 ... Control circuit drive power generation part 15
ACG ... Three-phase AC generator B ... Battery D1, D2, D3, D4, D5, D6 ... Diode S1, S2, S3 ... Thyristor

Claims (3)

A three-phase AC generator for supplying an AC voltage for battery charging, a diode bridge for rectifying the AC voltage of each phase in the three-phase AC generator,
A thyristor that is connected to an output terminal of each phase of the three-phase alternating current generator and controls the output terminal to be short-circuited;
A battery voltage detector that detects whether the charging voltage of the battery to be charged exceeds a preset threshold and outputs a detection signal;
When the detection signal is input, a thyristor firing start timing storage unit that outputs a thyristor on signal that turns on each thyristor;
Based on the thyristor on-signal, the thyristor, the battery charging device having a thyristor-on signal output unit for an ON state in the order of the phase of the phase of AC voltage. Further comprising an AC polarity detection unit for detecting the polarity of the alternating current each output of each phase before Symbol three-phase alternating-current generator,
The thyristor ON signal output unit outputs a control signal for turning on the thyristor corresponding to the phase in synchronization with polarity information of each phase output from the AC polarity detection unit. The battery charger according to 1.   3. The battery charging device according to claim 1, wherein the thyristor ignition start timing storage unit outputs the thyristor ON signal in synchronization with any one of the phases.

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