CN203859574U - Super-capacitor auxiliary power supply device - Google Patents

Abstract

The utility model discloses a supercapacitor auxiliary power supply device, which comprises a port A and a port B used to connect two ends of a load, and a bus current detection unit, a reverse preventing diode, and a supercapacitor group are sequentially arranged between the port A and the port B. A discharge circuit and a supercapacitor bank, and a supercapacitor bank charging circuit and a solid-state relay switch are sequentially arranged between the supercapacitor bank and port A. The utility model adds a supercapacitor group auxiliary power supply device to the output of the lead-acid storage battery of the existing electric car. When the electric vehicle motor is started, the current generated is 6-7 times that of normal driving, and part of it is stored by the supercapacitor group charging circuit. In the supercapacitor bank, when the lead-acid battery is insufficient, the energy in the supercapacitor is converted to assist the battery to supply power, so as to achieve the effect of stabilizing the starting peak current of the electric vehicle when driving, thereby increasing the cruising range.

Description

A supercapacitor auxiliary power supply device

technical field

The utility model relates to a power management device for electric bicycles, in particular to a supercapacitor auxiliary power supply device.

Background technique

The short-distance fast transportation tool in the city-the number of electric bicycles is already very large, and most of them use lead-acid batteries. Lead-acid battery is a kind of energy storage material with serious pollution. In the case of a huge usage base and no similar substitutes in the short term, improving battery discharge capacity and service life is an economical and environmentally friendly solution.

Utility model content

The purpose of this utility model is to provide a supercapacitor auxiliary power supply device, which can convert the energy in the supercapacitor to assist the battery to supply power, stabilize the starting peak current when the electric vehicle is running, prolong the service life of the battery, and improve the discharge capacity of the lead-acid battery.

The utility model adopts the following technical solutions:

A supercapacitor auxiliary power supply device, including a port A and a port B connected to both ends of a load, a bus current detection unit, a reverse prevention diode, a supercapacitor bank discharge circuit and a supercapacitor are sequentially arranged between the port A and the port B group, between the supercapacitor bank and port A, a supercapacitor bank charging circuit and a solid-state relay switch are arranged in sequence; the output end of the supercapacitor bank discharge circuit is connected to port A through a bus current detection unit, and the supercapacitor bank The current feedback end of the discharge circuit is connected to the input end of the solid state relay switch through the logic control circuit.

The logic control circuit comprises a current sampling hysteresis comparator circuit, a current feedback circuit and a control drive relay switch, and the current sampling hysteresis comparator circuit and the control drive relay switch are connected in series between the bus current detection unit and the solid state relay switch , the input end of the current feedback circuit is connected to the output end of the supercapacitor bank discharge circuit, and the output end of the current feedback circuit is connected to the input end of the bus current detection unit.

The current sampling hysteresis comparator circuit is composed of operational amplifier LM358 and its peripheral circuits.

The bus current detection unit is a Hall current sensor with a working range of 0-20A.

The supercapacitor bank is composed of six capacitor banks connected in series, each of which is composed of a voltage equalizing circuit board with a voltage of 2.7V.

The supercapacitor discharge circuit is a DC/DC Boost type power conversion circuit with an input voltage of 12V, an output voltage of 50V, and an auxiliary constant current function.

The supercapacitor charging circuit is a DC/DC Buck type power conversion circuit with an input voltage of 50V and an output voltage of 16V and 5A.

The utility model adds a supercapacitor group auxiliary power supply device to the output of the lead-acid storage battery of the existing electric car. When the electric vehicle motor is started, the current generated is 6-7 times that of normal driving, and part of it is stored by the supercapacitor group charging circuit. In the supercapacitor bank, when the lead-acid battery is insufficient, the energy in the supercapacitor is converted to assist the battery to supply power, so as to achieve the effect of stabilizing the starting peak current of the electric vehicle when driving, thereby increasing the cruising range. The same small current discharge can slow down the polarization effect of the battery plate, so that the battery life can be extended by about double.

Description of drawings

Fig. 1 is a functional block diagram of the utility model.

Detailed ways

As shown in the figure, a supercapacitor auxiliary power supply device includes port A and port B used to connect the two ends of the load. The port A and port B are also the output ends of the lead-acid battery in the electric vehicle and are used to provide power to the load. Electric energy; between port A and port B, a bus current detection unit, an anti-reverse diode, a supercapacitor bank discharge circuit and a supercapacitor bank are arranged in sequence, and a supercapacitor is also arranged in turn between the supercapacitor bank and port A Group charging circuit and solid state relay switch;

The output terminal of the supercapacitor bank discharge circuit is connected to port A through the bus current detection unit, and the current feedback terminal of the supercapacitor bank discharge circuit is connected to the input terminal of the solid state relay switch through the logic control circuit, and the opening and closing of the solid state relay is determined by the magnitude of the current . The logic control circuit comprises a current sampling hysteresis comparator circuit, a current feedback circuit and a control drive relay switch, and the current sampling hysteresis comparator circuit and the control drive relay switch are connected in series between the bus current detection unit and the solid state relay switch , the input end of the current feedback circuit is connected to the output end of the supercapacitor bank discharge circuit, and the output end of the current feedback circuit is connected to the input end of the bus current detection unit.

The current sampling hysteresis comparator circuit is composed of an operational amplifier LM358 and peripheral circuits. Since the operational amplifier LM358 is a common operational amplifier, its peripheral structure is also well-known to those skilled in the art, and the specific connection relationship will not be repeated here.

The bus current detection unit is a Hall current sensor used to detect the current output of the battery terminal, and its working range is 0-20A.

The supercapacitor bank is composed of six capacitor banks connected in series, each of which is composed of a voltage equalizing circuit board with a voltage of 2.7V.

The supercapacitor bank discharge circuit is a DC/DC Boost power conversion circuit with an input voltage of 12V, an output voltage of 50V, and an auxiliary constant current function (which can track the load voltage and maintain the battery constant current output). The current signal obtained by the Seoul current sensor is used as the input of its feedback terminal to realize the auxiliary constant current function. The current feedback terminal of the supercapacitor bank discharge circuit is connected to the output terminal of the Hall current sensor, and then the battery discharge current output and the supercapacitor bank discharge circuit output form an auxiliary constant current structure through the internal regulation of the supercapacitor bank discharge circuit.

The power terminal output of the charging circuit of the supercapacitor bank of the utility model is connected to the input terminal of the supercapacitor bank to realize the charging process, and the input terminal of the discharge circuit of the supercapacitor bank is connected between the positive and negative electrodes of the supercapacitor bank, thus the three constitute the charging process of the supercapacitor bank , Discharge circuit structure.

In actual use, when the solid-state relay switch is turned on under control, the lead-acid battery charges the internal supercapacitor bank through the forward DC/DC constant current and constant voltage charging circuit, and the maximum charging voltage reaches 16.20V. It can be seen that the power supply in the supercapacitor bank has been fully charged. The forward DC/DC constant current constant voltage charging circuit is a 50VDC to 16VDC output 10V-16.2V adjustable constant voltage, 5A constant current DC/DC Buck type power conversion circuit. During the charging process, the logic control circuit uses the current signal obtained by the Hall current sensor as the basis for the control input, and its working current is set to hysteresis control in the interval from 1A to 8A. When the feedback current value drops below 1A, the logic control circuit will turn on the solid-state relay, and the supercapacitor bank will receive charging energy; when the feedback current rises above 8A, the logic control circuit will close the solid-state relay, and the supercapacitor bank will stop charging, and Reduce battery load.

When the power of the lead-acid battery is reduced and the current is too low, the supercapacitor will release the internally stored current through the discharge circuit to supply the load of the tram, thereby improving the endurance of the tram.

According to the discharge characteristic curve of the lead-acid battery, about 60% of the capacity can be discharged at 0.6C-1C, and less than 30% of the capacity can be released at 2C, which can eliminate the peak current greater than 10A generated when the motor starts, and can make The current discharge of the battery is relatively stable, tending to be between 0.6C-1C, so as to increase the battery discharge capacity at a small current, prevent the polarization effect of the battery plate, prolong the battery life of the electric bicycle battery and improve the battery life. Therefore, it has great environmental protection and economic benefits. The design volume of the device is relatively compact, and the wiring is simple so that it is also convenient to refit and disassemble the existing electric vehicle in actual use.

Claims (7)

1. A supercapacitor auxiliary power supply device, comprising a port A and a port B connected to both ends of the load, characterized in that: between the port A and the port B, a bus current detection unit, a reverse diode, and a supercapacitor are arranged successively A group discharge circuit and a supercapacitor group, and a supercapacitor group charging circuit and a solid-state relay switch are arranged in sequence between the supercapacitor group and port A; the output end of the supercapacitor group discharge circuit is connected to the port through the bus current detection unit A, and the current feedback end of the discharge circuit of the supercapacitor bank is connected to the input end of the solid state relay switch through the logic control circuit. 2. The supercapacitor auxiliary power supply device according to claim 1, characterized in that: the logic control circuit comprises a current sampling hysteresis comparator circuit, a current feedback circuit and a control drive relay switch, and the current sampling hysteresis comparator The controller circuit and the control drive relay switch are connected in series between the bus current detection unit and the solid state relay switch, the input end of the current feedback circuit is connected to the output end of the supercapacitor bank discharge circuit, and the output end of the current feedback circuit is connected to the input end of the bus current detection unit . 3. The supercapacitor auxiliary power supply device according to claim 2, wherein the current sampling hysteresis comparator circuit is composed of an operational amplifier LM358 and its peripheral circuits. 4. The supercapacitor auxiliary power supply device according to claim 3, wherein the bus current detection unit is a Hall current sensor with a working range of 0-20A. 5. The supercapacitor auxiliary power supply device according to claim 4, characterized in that: the supercapacitor bank is composed of six capacitor banks connected in series, each of which is composed of a voltage equalizing circuit board with a voltage of 2.7V. 6. The supercapacitor auxiliary power supply device according to claim 5, wherein: the supercapacitor discharge circuit has an input voltage of 12V, an output voltage of 50V, and a DC/DC Boost type power converter with an auxiliary constant current function circuit. 7. The supercapacitor auxiliary power supply device according to claim 6, wherein: the supercapacitor charging circuit is a DC/DC Buck type power conversion circuit having an input voltage of 50V and an output voltage of 16V and 5A.