TWI441412B - Charging device and method - Google Patents

Description

Charging device and method

The present invention relates to a charging apparatus and method, and more particularly to a charging apparatus and method for applying a pulse charging technique.

Batteries are the main source of electricity for various types of electronic products in daily life. In order to enable efficient charging of batteries, many experts and scholars are actively studying how to make further improvements and breakthroughs in charging technology.

For example, in conventional charging techniques, charging a battery with periodic pulsed current is an improved method. Compared with other kinds of charging methods, the technology of charging with pulse current can spread the electrolyte with different concentration in the battery by adding a rest time in each charging cycle, and alleviate the reaction of chemical conversion energy, internal pressure and temperature. Lit and so on. In the general pulse charging technology, the square wave pulse current is usually used to charge the battery, but the square wave pulse current has a high current change rate, and the electrochemical reaction inside the battery often cannot quickly match and store the electric energy, and a large amount is generated. Heat loss.

Therefore, there is a need for a new charging device and charging method that can reduce heat loss during pulse current charging and improve charging efficiency.

Embodiments of the present invention provide a charging device that can adjust a frequency and a waveform of a pulse current, and can improve charging efficiency when a battery is charged by using a pulse current.

Embodiments of the present invention provide a charging device that provides a pulse current to charge at least one battery. The charging device includes a current generating module, a detecting module and a control module. The current generating module is configured to generate a pulse current. The detection module is configured to detect the pulse current received by the battery. The control module compares the pulse current with a preset current to generate a comparison result, and controls the current generation module to change the frequency of the pulse current according to the comparison result.

In an exemplary embodiment of the present invention, when the comparison result indicates that the pulse current is different from the preset current, the control module controls the current generating module to change the frequency of the pulse current according to the comparison result. The pulse current is made the same as the preset current. For example, when the comparison result shows that the pulse current is the same as the preset current, the control module controls the current generation module to maintain the frequency of the pulse current; when the comparison result shows that the pulse current is greater than the preset current, the control module controls the current generation mode. The group increases the frequency of the pulse current; when the comparison result shows that the pulse current is less than the preset current, the control module controls the current generation module to reduce the frequency of the pulse current. In addition, the detection module detects the current voltage of the battery. When the control module determines that the current voltage is greater than or equal to a saturation voltage, the control module outputs a stop signal to the current generation module, and the stop signal is used to indicate the current generation mode. The group stops generating pulse current.

The embodiment of the invention provides a charging method, which can adjust the frequency and waveform of the pulse current, and can improve the charging efficiency when the battery is charged by using the pulse current.

Embodiments of the present invention provide a charging method that provides a pulse current to charge at least one battery. The method comprises the steps of: generating a pulse current to the battery; detecting a pulse current received by the battery; comparing the pulse current with a predetermined current to generate a comparison result; and changing a frequency of the pulse current according to the comparison result.

In summary, the charging apparatus and method provided by the embodiments of the present invention can dynamically adjust the frequency of the pulse current output by the adjustment current generating module by detecting the voltage across the battery and the pulse current received by the battery. The battery is charged efficiently and can avoid overcharging of the battery. In addition, the charging device and the method provided by the embodiments of the present invention use the sine wave pulse current to charge the battery, and the sinusoidal pulse current has better charging efficiency than the square wave pulse current, and can effectively shorten the charging. Time and reduce heat loss.

For a better understanding of the features and technical aspects of the present invention, reference should be made to the accompanying drawings.

[First Embodiment]

Referring to FIG. 1 and FIG. 2, FIG. 1 is a functional block diagram of a charging apparatus according to a first embodiment of the present invention. 2 is a circuit diagram showing a charging device according to a first embodiment of the present invention. As shown, the user can connect the charging device 1 to the battery 2 such that the charging device 1 can provide a pulsed current to charge the battery 2. The battery 2 can be a lead-acid battery or other common rechargeable battery. The charging device 1 includes a current generating module 10, a detecting module 12, and a control module 14, a current generating module 10 and a detecting module. 12 is coupled to the battery 2 , and the control module 14 is coupled between the current generating module 10 and the detecting module 12 . The components of the charging device 1 will be described in detail below.

The current generating module 10 can output the generated pulse current to the battery 2 through the current path 10a, and can transmit the pulse current outputted from the battery 2 back to the current generating module 10 through the current path 10b. In practice, as shown in FIG. 2 , the current generating module 10 can include a DC power supply unit 102 , a commutation unit 104 , a resonant circuit 106 , a rectifying unit 108 , and a driving circuit 110 . The DC power unit 102 is coupled to the converter unit 104, the resonant circuit 106 is coupled between the converter unit 104 and the rectifier unit 108, and the drive circuit 110 is used to control the converter unit 104.

In the current generating module 10, the DC power unit 102 is configured to provide a DC current, and the DC current is output to the converter unit 104. In practice, the DC power unit 102 can be a variety of batteries that provide DC current or an output of an AC/DC rectifier. The present invention does not limit the type of the DC power supply unit 102 as long as it can be used to provide a DC current, and should belong to the scope of the DC power supply unit 102 of the present invention.

The commutation unit 104 is configured to convert a direct current into an alternating current, wherein the commutation unit 104 has two power switches 104a, 104b and a diode for rectification. Generally, during DC/AC conversion, the converter unit 104 can adjust the switching frequency of the power switch 104a and the power switch 104b so that the output current has a periodicity corresponding to the switching frequency when the polarity is switched. Please note that the function of the commutation unit 104 is to change the polarity of the direct current at a fixed frequency, so the waveform of the converted alternating current should be a square wave. Here, the converter unit 104 may be a half bridge converter, a full bridge converter, or a single crystal resonant circuit (Class E). The present invention does not limit the type of the converter unit 104 herein. Those having ordinary knowledge in the technical field are free to change.

The resonant circuit 106 should have at least a first inductor 106a and at least a first capacitor 106b for converting the alternating current into a sinusoidal alternating current. It should be apparent to those skilled in the art that when a fixed current is input to the series circuit of the first inductor 106a and the first capacitor 106b, the impedance characteristics of the first inductor 106a and the first capacitor 106b can fix the input. The waveform of the current is adjusted to the waveform of the sine wave. Therefore, the resonant circuit 106 can change the square wave alternating current output by the commutation unit 104 into a sine wave alternating current. Compared with the conventional pulse charging technology, the present invention can be greatly improved by adding a step of changing the current waveform. Charging efficiency of the charging device 1.

The rectifying unit 108 is configured to rectify the sine wave alternating current into a pulse current. The rectifying unit 108 can be a half-wave rectifying circuit, which uses two diodes to cut off the sinusoidal alternating current of the negative direction, and outputs only the forward sinusoidal alternating current, and the forward sinusoidal alternating current can be regarded as The pulse current. In practice, the rectifying unit 108 of the present invention can use not only a half-wave rectifying circuit but also other rectifying means, so that the sine wave current outputted by the rectifying unit 108 has the same polarity, that is, a continuous or discontinuous half-chord. Wave waveform. For example, the rectifying unit 108 can be a bridge rectifying circuit or other full-wave rectifying circuit that can generate a pulse current to improve the utilization efficiency of the sine wave alternating current.

The driving circuit 110 is controlled by the control module 14 and can be used to control the switching frequency of the power switch 104a and the power switch 104b of the converter unit 104, thereby changing the frequency of the alternating current output by the converter unit 104. As can be seen from the above, changing the frequency of the alternating current changes the frequency of the pulse current output by the rectifying unit 108, that is, the frequency of the pulse current received by the battery 2 during charging.

The detection module 12 is used to monitor the state of the battery 2. For example, the detection module 12 can detect the pulse current received by the battery 2 and the current voltage of the battery 2, and transmit the detected result to the control module 14. In practice, the detection module 12 can be any device having a voltage and current measurement function, which is connected to the battery 2 to detect necessary parameters during charging, and serves as a basis for the control module 14 to actively adjust the pulse current.

The control module 14 is configured to compare the pulse current with a preset current to generate a comparison result, and control the current generation module 10 to change the frequency of the pulse current according to the comparison result. The preset current may be the most appropriate current value for charging the battery 2. For example, when the comparison result shows that the pulse current is the same as the preset current, indicating that the pulse current is at the most appropriate current value and should be maintained, the control module 14 controls the current generation module 10 to maintain the frequency of the pulse current; The result shows that when the pulse current is greater than the preset current, it indicates that the pulse current is too high and should be corrected downward. The control module 14 controls the current generation module 10 to increase the frequency of the pulse current; when the comparison result shows that the pulse current is less than the preset current, It indicates that the pulse current is too low and should be lifted upwards, and the control module 14 controls the current generating module 10 to reduce the frequency of the pulse current.

In view of the above, it should be understood by those skilled in the art that when the control module 14 controls the switching frequency of the power switches 104a, 104b of the half-bridge converter unit 104 through the drive circuit 110, the switching frequency increase causes the pulse current to decrease. Conversely, a decrease in the switching frequency causes the pulse current to rise. Therefore, the control module 14 can adjust the switching current of the power switches 104a, 104b of the half-bridge converter unit 104 to adjust the pulse current to the most appropriate value to maintain the stability of the charging process.

In addition, when the control module 14 determines that the current voltage of the battery 2 is greater than or equal to a saturation voltage, a stop signal is outputted to the current generating module 10, and the stop signal indicates that the current generating module 10 stops generating the pulse current. That is, the control module 14 can determine whether the battery 2 is full. If the judgment result of the control module 14 indicates that the battery 2 is fully charged, the charging is stopped to prevent the occurrence of overcharge and increase the service life of the battery 2. .

[Second embodiment]

In the first embodiment of the present invention, the charging process of the charging device 1 for one battery 2 is explained, but the charging device 1 of the present invention can simultaneously charge a plurality of batteries 2. Referring to FIG. 3, FIG. 3 is a schematic circuit diagram of a charging device according to a second embodiment of the present invention. As shown in the figure, the second embodiment is different from the first embodiment in that the second embodiment discloses a circuit structure for simultaneously charging a plurality of batteries 2, and the detecting module 12 can be used to monitor a plurality of batteries 2 State. In addition, the charging device illustrated in FIG. 3 further includes a rectifying switch circuit 107 coupled between the resonant circuit 106 and the rectifying unit 108 and controlled by the control module 14 . When one of the batteries 2 is fully charged, the control module 14 can cut off the current path provided to the fully charged battery 2 through the rectifying switch circuit 107, thereby avoiding the wasted battery 2 being continuously charged and wasting power or posing a danger. .

For example, the rectifier switch circuit 107 has a first set of rectifier switch units 107a and a second set of rectifier switch units 107b. When the battery 2 above FIG. 3 has been fully charged and the battery 2 below FIG. 3 has not been fully charged, the control module 14 can control the first group of rectifier switch units 107a to be turned on, so that the resonant circuit 106 feeds the sine wave alternating current. The positive half cycle current will pass directly through the first set of rectifier switch units 107a and will no longer enter the fully charged battery 2. In addition, the control module 14 can control the second group of rectifier switch units 107b to be turned off, so that the negative half cycle current of the sinusoidal alternating current fed by the resonant circuit 106 still enters the battery 2 that has not been fully charged without passing through the second group. Rectifier switch unit 107b.

Conversely, when the battery 2 below FIG. 3 has been fully charged and the battery 2 above FIG. 3 has not been fully charged, the control module 14 can control the first group of rectifier switch units 107a to be turned off, so that the resonant circuit 106 feeds the strings. The positive half cycle current of the alternating current current will still enter the battery 2 that has not been fully charged without passing through the first group of rectifier switch units 107a. In addition, the control module 14 can control the second group of rectifier switch units 107b to be turned on, so that the negative half-cycle current of the sinusoidal alternating current fed by the resonant circuit 106 directly passes through the second group of rectifier switch units 107b and no longer enters the Fully charged battery 2.

In practice, the switches S1 and S2 in the first group of rectifier switch units 107a and the second group of rectifier switches unit 107b may be a type of transistor switch, and the control module 14 controls whether the transistor switch is turned on or off. Alternatively, the switches S1, S2 can be implemented using relays that are also controlled by the control module 14 to conduct or not. In addition, the switches and diodes of the first group of rectifier switch units 107a and the second group of rectifier switch units 107b can be integrated into a thyristor element (SCR) such that the first group of rectifier switch units 107a and the second group of rectifier switches Unit 107b also has the function of switching and rectifying.

[Third embodiment]

The charging device described above will be described more clearly in conjunction with the charging method of the present invention.

Please refer to FIG. 1 and FIG. 4 together. FIG. 4 is a flow chart showing a charging method according to a third embodiment of the present invention. As shown, in step S302, the current generating module 10 of the present invention generates a pulse current to the battery 2, wherein the waveform of the pulse current can be a continuous or discontinuous half-wave waveform. Next, in step S304, the detecting module 12 of the present invention can detect the pulse current received by the battery 2. Of course, the detection module 12 can detect the current voltage of the battery 2 together. In step S306, the control module 14 is configured to compare the pulse current with a preset current to generate a comparison result. In practice, the pulse current and the preset current value may be input together to a subtractor, so that the pulse current is Subtract the preset current, so the output of the subtractor should be zero, positive or negative.

In step S308, the control module 14 can control the current generating module 10 to change the frequency of the pulse current according to the comparison result. For example, when the result of the subtracter output of step S306 is zero, indicating that the pulse current is at the most appropriate current value and the current state should be maintained, the control module 14 should control the current generating module 10 to maintain the frequency of the pulse current, so that the pulse current The current value does not change. If the result of the subtracter output in step S306 is positive, indicating that the pulse current is too high and should be corrected downward, the control module 14 should control the current generating module 10 to increase the frequency of the pulse current, so that the current value of the pulse current is lowered. . If the result of the subtracter output in step S306 is a negative value, indicating that the pulse current is too low and should be lifted upward, the control module 14 controls the current generating module 10 to reduce the frequency of the pulse current, so that the current value of the pulse current is increased.

In addition, after step S308, the control module 14 can further compare the values of the current voltage and a saturation voltage. When the current voltage exceeds or equals the saturation voltage, the display battery 2 is fully charged, so the control module 14 can control the current generation module 10 to stop generating the pulse current.

[Fourth embodiment]

In a second embodiment of the present invention, a circuit architecture that can simultaneously charge a plurality of batteries 2 is illustrated. However, the circuit architecture of the resonant circuit 106 can be further modified. Referring to FIG. 5, FIG. 5 is a schematic circuit diagram of a charging device according to a fourth embodiment of the present invention. As shown in Fig. 5, the fourth embodiment is different from the second embodiment in that the charging device 1a of the fourth embodiment further has a CLL resonance circuit 106' and a transformer 112 so that the charging device 1a is isolated from the battery 2. Here, the CLL resonant circuit 106' further has a second inductor 106c, the second inductor 106c is connected between the first capacitor 106b and the system ground, and the transformer 112 can have a primary side coil N1 and a secondary side coil N2. And a magnetic core Tr. Thereby, the charging system 1a of the fourth embodiment can be made more stable than the second embodiment through the CLL resonant circuit 106' and the transformer 112 for isolation.

In addition, the transformer 112 can further increase the number of the secondary side coils N2, so that the charging device 1a can simultaneously charge more of the batteries 2. Referring to FIG. 6, FIG. 6 is a schematic circuit diagram of another charging device according to a fourth embodiment of the present invention. As shown in Fig. 6, the transformer 112' may have more than one set of secondary side coils N2, and the charging device 1a may simultaneously supply charging currents of the plurality of sets of batteries 2 in the case where the charging device 1a can be used.

[Fifth Embodiment]

In a fourth embodiment of the present invention, a circuit architecture having both a CLL resonant circuit 106' and a transformer 112 is illustrated. However, in practice, the charging device may have only a transformer to achieve an isolated charging. Referring to FIG. 7, FIG. 7 is a schematic circuit diagram of a charging device according to a fifth embodiment of the present invention. As shown in FIG. 7, the fifth embodiment is different from the fourth embodiment in that the charging device 1b of the fifth embodiment is provided with the resonant circuit 106 in combination with the transformer 112 instead of the CLL resonant circuit 106' with the transformer 112. The effect of the charging device 1b being isolated from the battery 2 can be achieved.

Of course, the transformer 112 can also increase the number of secondary side coils N2 so that the charging device 1b can simultaneously charge more of the battery 2. Referring to FIG. 8, FIG. 8 is a schematic circuit diagram of another charging device according to a fifth embodiment of the present invention. As shown in Fig. 8, the transformer 112' may have more than one set of secondary side coils N2, and the charging device 1b may simultaneously supply charging currents of the plurality of sets of batteries 2 in the case where the charging device 1b can be used.

[Sixth embodiment]

In addition to the fact that the resonant circuit can be varied, the commutation unit can also be suitably modified. Referring to FIG. 9, FIG. 9 is a schematic circuit diagram of a charging device according to a sixth embodiment of the present invention. As shown in Fig. 9, the charging device 1c of the sixth embodiment reduces the number of power switches in the commutation unit such that the commutation unit 104' and the resonance circuit 106 constitute a circuit structure of a single crystal (class E) resonance. In a practical manner, the DC power supply unit 102 can be electrically connected to the converter unit 104' and the resonant circuit 106 through the third inductor 106d, wherein the first inductor 106a, the first capacitor 106b and the third inductor 106d are all resonant elements.

[Seventh embodiment]

Referring to FIG. 10, FIG. 10 is a schematic circuit diagram of a charging device according to a seventh embodiment of the present invention. As shown in FIG. 10, the charging device 1d of the seventh embodiment exemplifies another circuit configuration of a single crystal (class E) resonance. Here, the DC power supply unit 102 can be electrically connected to the converter unit 104' and a resonant circuit 106" through the fourth inductor 106e, wherein the resonant circuit 106" includes a second capacitor 106f, a first inductor 106a, and a first Capacitor 106b. Here, the fourth inductor 106e has a large inductance value that does not participate in resonance, and the second capacitor 106f, the first inductor 106a, and the first capacitor 106b are all resonant elements.

In summary, the charging device and method provided by the embodiments of the present invention can detect the voltage across the battery and the pulse current received by the battery, and feedback the frequency of the pulse current output by the current generating module, thereby controlling the pulse. The current is at the most appropriate value while maintaining the stability of the charging process. In addition, the present invention can prevent the battery from being overcharged by monitoring the current voltage of the battery to determine whether to continue charging. Furthermore, the charging device and the method provided by the embodiments of the present invention use the sine wave pulse current to charge the battery. Compared with the square wave pulse current, the sine wave pulse current has better charging efficiency and can be effectively shortened. Charging time and reducing heat loss.

The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of the invention, and the equivalents of the invention are included in the scope of the invention.

1, 1a, 1b, 1c, 1d. . . Charging device

2. . . battery

10. . . Current generation module

10a, 10b. . . Current path

12. . . Detection module

14. . . Control module

102. . . DC power unit

104, 104’. . . Converter unit

104a, 104b. . . Power switch

106, 106', 106"... resonant circuit

106a, 106c, 106d, 106e. . . inductance

106b, 106f. . . capacitance

107. . . Rectifier switch circuit

107a. . . First set of rectifier switch unit

107b. . . Second group of rectifier switch units

S1, S2. . . switch

108. . . Rectifier unit

110. . . Drive circuit

112, 112’. . . transformer

N1, N2. . . Coil

Tr. . . core

S302~S308. . . Step flow

1 is a functional block diagram of a charging device in accordance with a first embodiment of the present invention.

2 is a circuit diagram showing a charging device according to a first embodiment of the present invention.

3 is a circuit diagram of a charging device in accordance with a second embodiment of the present invention.

4 is a flow chart showing a charging method in accordance with a third embodiment of the present invention.

FIG. 5 is a schematic circuit diagram of a charging device according to a fourth embodiment of the present invention.

6 is a circuit diagram showing another charging device according to a fourth embodiment of the present invention.

FIG. 7 is a circuit diagram showing a charging apparatus according to a fifth embodiment of the present invention.

FIG. 8 is a circuit diagram showing another charging device according to a fifth embodiment of the present invention.

FIG. 9 is a circuit diagram showing a charging apparatus according to a sixth embodiment of the present invention.

FIG. 10 is a circuit diagram showing a charging apparatus according to a seventh embodiment of the present invention.

1. . . Charging device

2. . . battery

10. . . Current generation module

10a, 10b. . . Current path

12. . . Detection module

14. . . Control module

Claims (9)

A charging device for supplying a pulse current to charge at least one battery, the charging device comprising: a current generating module for generating the pulse current; a detecting module coupled to the battery for detecting the battery And receiving the pulse current; and a control module coupled between the current generating module and the detecting module to generate a comparison result between the pulse current and a preset current, the control mode The group controls the current generating module to change a frequency of the pulse current according to the comparison result, wherein the waveform of the pulse current is a sine wave waveform. The charging device of claim 1, wherein when the comparison result indicates that the pulse current is different from the preset current, the control module controls the current generating module to change the pulse according to the comparison result. The frequency of the current is such that the pulse current is the same as the preset current. The charging device of claim 1, wherein the detecting module detects a current voltage of the battery, and when the control module determines that the current voltage is greater than or equal to a saturation voltage, the control module A stop signal is output to the current generating module, and the stop signal indicates that the current generating module stops generating the pulse current. The charging device of claim 1, wherein the current generating module comprises: a DC power supply unit for providing a DC current; and a converter unit coupled to the DC power unit for the DC Current Converting into an alternating current with one of the frequencies; a resonant circuit coupled to the converter unit, the resonant circuit having at least a first inductor and at least a first capacitor for converting the alternating current into a sine wave alternating current a rectifying unit coupled to the resonant circuit to rectify the sinusoidal alternating current into the pulse current; and a driving circuit coupled to the commutating unit and the control module, controlled by the control module to control the The commutation unit changes the frequency. The charging device of claim 4, further comprising: a rectifying switch circuit coupled between the resonant circuit and the rectifying unit, controlled by the control module for selectively turning on the pulse Current to the battery. A charging method for supplying at least one battery by charging a pulse current, the method comprising the steps of: generating the pulse current to the battery; detecting the pulse current received by the battery; comparing the pulse current with a preset And generating a comparison result; and changing a frequency of the pulse current according to the comparison result, wherein the waveform of the pulse current is a sine wave waveform. The charging method according to claim 6, wherein the waveform of the pulse current is a half sine wave waveform. The charging method of claim 6, wherein the step of comparing the pulse current with the preset current to generate the comparison result further comprises the following steps: Determining that the pulse current is greater than, equal to, or less than the preset current, thereby generating the comparison result; wherein, when the comparison result indicates that the pulse current is different from the preset current, changing the result according to the comparison result The frequency of the pulse current is such that the pulse current is the same as the preset current. The charging method of claim 6, further comprising the step of: detecting a current voltage of the battery; wherein, when the current voltage is greater than or equal to a saturation voltage, the generating of the pulse current is stopped.