TW200540442A - Quick charging system of predictive battery and the method thereof - Google Patents

Abstract

The present invention relates to a quick charging system of predictive battery and the method thereof. Instead of depending on a precise battery mathematic model, the system of the invention takes advantage of a voltage detecting and converting circuit to convert a closed-circuit voltage of the battery according to the charging status of the battery into a digital value. In addition, the digital value is transmitted to a predictive controller to output a fixed current so as to charge the battery by use of the predictive controller to transfer the digital value to a programmable current source. Meanwhile, the predictive controller is capable of obtaining the voltage of the next battery by an algorithm and obtaining a more suitable charging current in accordance with the voltage to charge the battery for several circles until the battery is full. Accordingly, the invention applies the prediction theory to predict the charging status of the next stage and determines the most suitable value of the charging current; thus, it has the capability to react in advance and to prevent accidentally events so as to provide: (1) better safety, which can prevent the over-charging of batteries effectively; and (2) a faster charging speed, which enables the determination of the charging status in advance so as to define the most suitable charging conditions. As demonstrated by experiments, the charging speed for charger of the predictive batteries is higher than charger of common fixed-voltage and fixed-current batteries by 16% approximately.

Description

200540442 V. Description of the invention (1) [Technical field to which the present invention pertains] The present invention is a predictive battery fast charging system and method, and belongs to the technical field of battery charging technology and safe charging conditions. [Previous technology] According to commonly used secondary batteries, there are lead-acid batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and ion-ion batteries. Therefore, many charging strategies for the foregoing batteries have been developed, such as 疋 > Constant trickle current charge), Constant current charge and Constant Voltage-Constant Current Charge, or constant voltage limit current, two-stage charging. In addition, the most widely used constant voltage and constant current charging strategy is to charge the battery with a constant current at the beginning, and the charging has reached the set final voltage. After the voltage is set, the charger is set to the same value. A constant voltage of a voltage value charges the battery, and the charging current is automatically reduced; when the charging current is reduced to zero, the battery is considered to be 100% fully charged. [Summary of the Invention] 1. Problem 1 · 疋 > The monthly charging strategy has the advantages of simple circuit structure and low cost. However, the charging time is too long. Because it takes more than ten hours, it is only used at night (Overnight- Charge). 2 · The constant current charging strategy uses a larger current than the trickle, but its disadvantage is that it is not easy to achieve the 100% full charge voltage detection accuracy required by its charging system, so undercharge or overcharge often occur (〇 vercharge) phenomenon.

200540442 V. Description of the invention (2) 3. The constant-voltage constant-current charging strategy was originally overcharged, but it also prolonged the charging time. Z effectively prevents the battery from generating a current charging strategy. The open-loop control and traditional constant-voltage constant-power Its security is insufficient. According to the theory of control theory, two, the means to solve the electric system =; description = shall: =:-a type of predictive battery fast charging according to the battery's charging status is not; type: but the first response and preventive ability, With; flow! : There is a solid matter to effectively avoid overcharging of the lithium-ion battery. Ann: Yes Fast speed: You can know in advance that the battery is charging 4 times: =:, fork charging conditions, so the charging speed is fast. [Embodiment] As shown in the first figure, it is a block diagram of the electrical system disclosed in the present invention. It consists of a predictive controller (pc ;, 'voltage :: f charge and replace MVSC), a controllable current source (ccs), a timer (, /' 彳, and turn (S). Among them, the predictive controller (PC ) Is mainly used to pre-change the charging state of the switch and obtain the ideal charging current. The value sent by the control unit (PC) of the controllable electric π i pool is converted to the charging current to the battery; Converter (vsc) ± To measure the open circuit I of the battery; detect the closed circuit voltage (vc) and convert it to a digital value (Nvfl, Nvc), so = (v〇) and the value is sent to the predictive control Because the internal controller of the predictive controller (pc) uses this method, the predictive controller (PC) will send the predicted and bamboo parameters as parameters 200540442 V. Description of the invention (3) to predict the battery The next charging state and the ideal charging current (Nic) are obtained. The timer (T) is mainly used to generate a signal to control the on and off of the switch (S). When the switch (S) is open, the voltage detection and converter ( VSC) will measure the open circuit voltage (VG) of the battery and convert it to a digital value (NVG); when the switch is off (S) and the system is on, Charge the battery and convert the battery's closed circuit voltage (vc) into a digital value (NVc). The predictive battery fast charging system proposed by the present invention is composed of four working states, as shown in the second figure. Sense State, Constant Current Charge State, Calculation State, and Prediction Charge State. First, the system works in the detection state, and the system measures the battery separately Open circuit voltage (VG) and closed circuit voltage (vc), if the closed circuit voltage is less than 4 · 2 V 'the system will enter a constant current charging state, at this time the system will charge the battery with a fixed current for a while; otherwise, the system will enter the calculation The status will show the next charging state of the battery and Libang, the charging current. Then the system enters the predictive charging state, and the system charges the battery for a period of time with the Lishen charging current. After a period of charging, the system will return to detection The state detects the battery voltage. As shown in the third figure, it is a program flow chart of the predictive battery fast charging system. First, the battery The closed circuit voltage (Vc) of the cell (β) is converted into a digital value (NVe) by the voltage detection and converter (VSC), and then this digital value is transmitted to the predictive controller (PC). In this case, the closed circuit voltage of the battery The digital ^ is less than 2V, the predictive controller (PC) will send a digital value (Nic) to the controllable thunder source (CCS) to generate a certain current to charge the battery. During this charge ^

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200540442

5. Description of the invention (4) The charging method of the 'predictive battery charging system' is the same as the constant current charging system. If the closed circuit voltage (V.) of the battery is greater than or equal to 4 · 2V, the open circuit voltage (vG) of the battery will be converted into a digital value (Nv.) By the voltage detection and converter (vsc) and transmitted to the predictive control. In the device (pC), the next prediction = empty system (PC) uses the algorithm to obtain the next battery voltage, and based on this, a more appropriate charging current (Ie) is used to charge the battery. This cycle starts and ends until "^ 4 · 2V". For the convenience of explanation, in the following embodiments, the first-order prediction model GM (1,1) in the prediction theory is used to complete the voltage prediction work, and the description is made with the lithium-ion battery used in the mobile phone, but the purpose is only to It is easy to understand the content of the method, and is not intended to limit the methods and objects of the method. [Specific embodiment] In a specific embodiment of the present invention, a 60 mAh bell-ion battery (B) is used as an experimental object. As shown in the fourth figure, it is a prediction result using a ¾ gray prediction plate type G M (1,1). It can be seen from the figure that the ^ μ (1,1) model can accurately obtain the battery voltage at the next time. A block diagram of the first embodiment is shown in the fifth figure. Its main devices are digital / analog converter (DAC), voltage / current converter (VIC), lithium-ion battery (B), analog / digital converter (ADC), GM (1, 1) data sheet and microprocessor (Pc); wherein the microprocessor (MP) is a low-cost microprocessor with no floating-point arithmetic capability, and the GM (1,1) data table may be composed of read-only memory (ROM). First, the battery knows that the voltage is converted to a digital value through an analog / digital converter (A d [) and latched (Latch) in the microprocessor (Mp). The microprocessor (MP) will put the previous Stored (t — up),% (t

Page 8 200540442 V. Description of the invention (5)-2T), V0 (t-3T), send it to the GM (1, 1) data sheet to find out an open-circuit voltage VG (t-T), then, The microprocessor (MP) will find the most suitable charging current based on this value. The system converts the digital value of this charging current from an analog / digital converter (DAC) to an analog voltage. Finally, the system will then drive accordingly. The voltage / current converter (v 丨 C) outputs an appropriate charging current to charge the battery. This charging current can be expressed as follows: ~ ^ (1) where ~ is the internal resistance of the lithium ion battery and yS is the gain parameter. Finally, the variable current source will charge the battery according to the digital value (NIc) transmitted by the predictive controller (PC), and then iterates until the battery is fully charged. From Equation (1), it can be known that when the predicted open-circuit voltage is less than 4 · 2V (i.e ·) lithium-ion battery charge voltage, the system will charge the battery with a larger charging current to shorten the battery charging time. In other words, when the predicted open circuit voltage is greater than or equal to 4.2V, the system will charge the battery with a smaller charging current to avoid danger due to overcharging of the lithium-ion battery. It is worth noting that when the point = 0, the predictive battery charge current will become ~ ′, just like constant voltage charging. Therefore, when / 5 = 0, the predictive battery fast charging system is just like a constant current and constant current charging system. That is, as long as / 3 > 〇, the charging speed of the predictive battery fast charging system disclosed by the user of the present invention will be faster than the conventional constant voltage and constant current charging. As shown in the sixth figure, a circuit diagram of the voltage / current converter (V 1 C) in this embodiment. It is mainly composed of operational amplifier (0PA), metal oxide field

200540442

The output current equation of the effect transistor (FET) and resistor (Rf) is shown below: 'Controllable current generator / (2) where ’VDAC 疋 digital / analog converter⑼ac)

Fig. 7 shows another embodiment. Its main devices are digital / class, conversion (DAC), voltage / current converter (ViC), electronic converter ratio / digital converter (ADC), and microprocessor (% p). High-level digital signal processing with floating-point arithmetic capability; Completion of calculation of GM (1,1) data table.% 100, battery terminal voltage VG (t) is converted to a digital value by analog / digital converter (ADC) \ (t), and latch it in the microprocessor (MP). The microprocessor (Mp) will store the previously stored% (t — τ) '— 2T), V0 (t — 3T) , With V〇 (t) using GM (1,

i) The algorithm predicts the next open-circuit voltage Vq (t-t), and then the microprocessor (MP) brings this value into equation (1) to find the most suitable charging current. The value is converted into an analog voltage by a digital / analog converter (DAC). Finally, the system drives the voltage / current converter (VIC) to charge the battery according to a proper charging current, and so on until the battery is full. As shown in the eighth figure, it is the experimental result of the embodiment. It can be clearly seen that the predictive battery fast charging method disclosed in the present invention can complete the charging in only 146 minutes, which is faster than the traditional charging method in 174 minutes. Took 2 6 minutes, about

Page 10 200540442 V. Description of the invention (7) The charging speed is improved by 16%. Although the present invention is disclosed in the above two preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make some modifications and retouching without departing from the spirit and scope of the present invention. The scope of protection of the invention shall be determined by the scope of the attached invention.

Page 11 200540442 Brief description of the drawings [Illustration] The first picture is a predictive battery fast charging system. The second figure is a state diagram of the predictive battery fast charging system. $ 三 图 is the program flow chart of predictive battery fast charging system. The twenty-fourth figure is the prediction result of the first-order gray prediction model G M (1,1). The fifth figure is the first embodiment of the predictive battery fast charging system. The sixth figure is a voltage / current conversion circuit. FIG. 7 is a second embodiment of a predictive battery fast charging system. The eighth figure shows the experimental results of predictive battery fast charging system and traditional charger (a) charging current, (b) open circuit voltage. '[Symbol part] Voltage detection and converter (VSC) Timer (T) Closed voltage (VC) Digital value (NVC) Digital / analog converter (DAC) Microprocessor (MP) Field effect transistor (FET) ) Analog / digital converter (ADC) Predictive controller (PC) Controllable current source (CCS) Open circuit voltage (V 〇) Battery (B) Charging current (IC) f Voltage / current converter (VIC) Operational amplifier ( 0ΡΑ) Densaka U f)

Claims (1)

200540442 6. Scope of patent application 1. A predictive battery fast charging method is composed of a predictive controller, a voltage detection and converter, a controllable current source, a timer and a switch; wherein, the charging method is Including: a. The voltage detection and converter measures the battery's open circuit voltage and closed circuit voltage and converts them to a digital value, and sends this value to the predictive controller; b. The predictive controller detects the voltage The data sent from the converter are used as parameters to predict the next charging state of the battery and to obtain the charging current value; c. The charging current value is transmitted to a controllable current source for converting the charging current to charge the battery; therefore After a number of cycles, the battery will be fully charged. 2. — A predictive battery fast charging method is composed of a detection state, a constant current charging state, a calculation state, and a predictive charging state. Among them, the charging method includes: a. The system first works in the detection state, Measure the open circuit voltage and closed circuit voltage of the battery separately. If the closed circuit voltage is less than 4.2 V, the system will enter the constant current charging state; otherwise, the system will enter the calculation state; b. When the system is in the constant current charging state, Charge the battery with a fixed current; c. When the system is in the calculation state, it will calculate the next charging state of the battery and obtain a better charging current based on this; d. After the calculation state, the system enters the predictive charging state and uses this Better charging current to charge the battery; after charging for a period of time, the system will return to the detection state; Page 13 200540442 Six 'Yu please patent Fanyuan ___ Therefore, after the above-mentioned multiple cycles, full charge. Jiao Ze battery will reach 3 · — a type of predictive battery fast charging device, strong controller, voltage detection and converter, controllable mine = home system includes: predictive control and battery; machine source, Ye Shi The device switches to a predictive control state, which is connected to the wheel end of the controllable cryogenic pressure detection and converter, which is used as the A cat, and L / original wheel input and electrical state, and a better Battery charging current ;, the next charge state of the battery, a voltage detection and converter; ^ connected to the aforementioned input terminal and the output terminal of the battery, as a measured & controller output voltage and converted it into Digital value; 'Open-circuit voltage and closed-circuit-controllable current source; connected to the output of the switch-on switch, used to charge the battery by converting the predicted electric current value into a charging current; It is connected to the output terminal of the aforementioned controllable current source and the voltage and closed circuit voltage of the battery; the electric circuit is also open circuit. • A juice timer; it is used to determine the closing and opening time of the aforementioned switch; Because "the voltage detection and converter measures the open circuit voltage and the closed voltage of the battery and converts them into digital values, this value is sent to the predictive controller" and the controller detects the voltage The information sent by the converter is used to predict / predict the next charging state of the battery and obtain the value of the charging electric current. Ton / ο seeks k to a controllable current source, and converts this charging current value to Charging electricity Page 14 200540442 Sixth, the scope of patent application is to charge the battery; after several cycles mentioned above, the battery will reach full charge, so as to shorten the charging time and reach the fully charged state quickly. 4. The predictive battery fast charging system according to item 3 of the scope of the invention; wherein the controllable current source includes at least a digital / analog converter and a voltage / current converter. 5. The predictive battery fast charging system according to item 4 of the scope of the invention; wherein the voltage detection and converter includes at least one analog / digital converter. 6. The predictive battery fast charging system according to item 4 of the scope of the invention; wherein the predictive controller includes at least one microprocessor. 7. The predictive controller as described in item 6 of the scope of the application; wherein the microprocessor has at least a device or software that achieves a prediction calculation and a person who determines the charging current based on the prediction result. Page 15