CN1209254C - Energy regeneration auxiliary power for electric bicycle - Google Patents

Abstract

The invention discloses an auxiliary power source for energy regeneration of an electric bicycle, which includes a motor, a main battery, and an additional auxiliary battery. The auxiliary battery is connected in parallel with the main battery, and a drive controller is connected between the motor and the main battery to drive The power part of the controller is a three-phase inverter bridge for the permanent magnet brushless DC motor, and the power part of the permanent magnet brushed DC motor is a half bridge structure; the main battery is connected to the drive controller through switch S1, and the auxiliary battery is connected to the drive control The inverter is connected through the switch S2, and the electric energy recovered by the regenerative braking of the motor charges the auxiliary battery through the drive controller. Therefore, there is no need for DC/DC step-down, and since the power consumption of the auxiliary equipment is small, the regenerative braking of the motor can basically satisfy the charging of the auxiliary battery. The invention saves the DC/DC step-down device in the drive system, and also improves the driving mileage of the electric bicycle once charged because the regenerative braking feedback energy is effectively used.

Description

Electric bicycle energy regeneration auxiliary power supply

technical field

The invention belongs to the technical field of driving control of electric bicycles, and can be further applied to the field of driving control of electric vehicles such as electric tricycles and electric motorcycles. The utility model relates to an auxiliary power source for energy regeneration of an electric bicycle.

Background technique

At present, the drive control system of electric bicycles is composed of batteries, motors and drive controllers. The battery provides energy for the motor and auxiliary equipment at the same time, such as lights, sensors, and the power required by the controller. The battery is charged with a special charger. The battery is mostly maintenance-free lead-acid battery or nickel-metal hydride battery. After the vehicle travels a certain distance, the battery is charged when the battery voltage drops to a certain lower limit. Since the working voltage of the auxiliary equipment is lower than the rated voltage of the motor, the voltage of the battery is configured according to the voltage required by the motor, so the battery needs to be DC/DC stepped down to supply the auxiliary equipment, as shown in Figure 1.

Contents of the invention

The object of the present invention is to provide an electric bicycle energy regeneration auxiliary power supply, which is characterized in that: in addition to the main battery providing the energy required for the motor to run, an auxiliary battery and an interface circuit composed of relays S1 and S2 are also provided.

The present invention is also characterized in that the auxiliary battery is directly connected to the auxiliary equipment to supply power to the auxiliary equipment, and the electric energy recovered by the regenerative braking of the motor is used for charging when the vehicle brakes or goes downhill.

The electric bicycle energy regeneration auxiliary power supply of the present invention includes a motor and a main battery, the main battery provides the energy required for the operation of the motor, and its voltage is configured according to the rated voltage of the motor; it also includes an additional auxiliary battery, wherein the auxiliary battery is directly connected to the auxiliary equipment , directly supply power to the auxiliary equipment, the voltage of the auxiliary battery is selected according to the working voltage of the auxiliary equipment, and a drive controller is connected between the motor and the main battery, the power part of the drive controller is a three-phase inverter bridge for the permanent magnet brushless DC motor, For the permanent magnet brushed DC motor, its power part is a half-bridge structure; the main battery is connected to the drive controller through switch S1, and the auxiliary battery is connected to the drive controller through switch S2. The off and on states of the relay S1 and the relay S2 are switched, and the electric energy recovered by the regenerative braking of the motor charges the auxiliary battery through the drive controller.

Since the main battery is connected to the drive controller through the relay S1, and the auxiliary battery is connected to the drive controller through the relay S2, the auxiliary battery is directly connected to the auxiliary equipment. The main battery provides the energy required for the operation of the motor, and its voltage is configured according to the rated voltage of the motor; the voltage of the auxiliary battery is selected according to the working voltage of the auxiliary equipment, so it does not need to go through DC/DC step-down, and directly supplies power to the auxiliary equipment.

When the vehicle is running normally, the relay S1 is turned on, and the relay S2 is turned off. The main battery provides the energy required for the motor to run through S1 and the drive controller, and the auxiliary battery directly supplies power to the auxiliary equipment. The two circuits are completely independent.

When the vehicle brakes, the relay S1 is turned off and the relay S2 is turned on, as shown in FIG. 4 . Because the vehicle brakes, the main battery does not need to supply power to the motor, and the main battery power supply circuit is cut off. At this time, the motor is working as a generator, and the regenerative energy of the motor is recovered by the auxiliary battery through the relay S2, and supplies power to the auxiliary equipment. In addition, the relay S1 is turned off to cut off the electrical connection between the main battery and the motor, so as to ensure the feedback energy to charge the auxiliary battery.

Since the power consumption of the auxiliary equipment is small, the regenerative braking of the motor can basically meet the charging of the auxiliary battery, so that no special charger is required. When the electric bicycle is running normally, the drive controller uses the electric energy in the power battery to drive the motor, and then drives the bicycle forward; The gravitational potential energy loss during the time is converted into electrical energy and stored in the auxiliary battery to provide the energy required by the auxiliary equipment.

The invention can save the DC/DC step-down device in the drive system, and reduce the cost of the vehicle due to the low price of the small-capacity lead-acid battery; since the energy fed back by regenerative braking is effectively used, it can increase the cost of charging the electric bicycle at one time. While driving mileage, it also saves energy; in addition, due to the use of regenerative braking of the motor, the wear of the mechanical brake part is reduced, the life of the electric bicycle is prolonged, and the braking noise is also reduced; the technical content of the electric bicycle is improved, and the Market Competitiveness.

Description of drawings

Fig. 1 is a schematic diagram of an electric bicycle driving system;

Fig. 2 is a schematic diagram of an electric bicycle drive system with an auxiliary power supply;

Fig. 3 is a schematic diagram of the current direction when the electric bicycle is in a normal working state;

Fig. 4 is a schematic diagram of the current direction when the electric bicycle is under regenerative braking;

Fig. 5 is a schematic diagram of the current direction when the power device is turned off under the regenerative braking state of the permanent magnet brushless DC motor;

Fig. 6 is a schematic diagram of the current direction when the power device is turned on under the regenerative braking state of the permanent magnet brushless DC motor.

Detailed ways

Below in conjunction with accompanying drawing and the embodiment that inventor provides. The present invention is described in further detail.

The invention is a new type of energy storage method for electric bicycles, that is, the main battery provides the energy required for the operation of the motor, and its voltage is configured according to the rated voltage of the motor; an auxiliary battery is also configured, which is directly connected to the auxiliary equipment, and its voltage is configured according to the auxiliary equipment The working voltage is selected, so it does not need to go through the DC/DC step-down, and directly supplies power to the auxiliary equipment, as shown in Figure 2.

Since the power consumption of the auxiliary equipment is small, the regenerative braking of the motor can basically meet the charging of the auxiliary battery, so that no special charger is required. When the electric bicycle is running normally, the drive controller uses the electric energy in the power battery to drive the motor, and then drives the bicycle forward, while the auxiliary battery supplies power to the auxiliary equipment, and the two sets of circuits are completely isolated; when the vehicle brakes or goes downhill, the motor works at In the working condition of the generator, the kinetic energy when the bicycle is running and the gravitational potential energy loss when going downhill are converted into electrical energy and stored in the auxiliary battery to provide the energy required by the auxiliary equipment.

The invention is applicable to electric bicycles adopting various motors, accumulators and drive controller power devices. Motors include permanent magnet brushless DC motors and permanent magnet brushed DC motors; batteries include lead-acid batteries, lithium-ion batteries, and nickel-metal hydride batteries; power devices for drive controllers can use GTR (power transistors), MOSFETs (metal-oxide- Semiconductor Field Effect Transistor), IGBT (Insulated Gate Bipolar Transistor), GTO (Gate Turn Off Thyristor).

When the vehicle is working normally, the relay S1 is turned on and the relay S2 is turned off, as shown in FIG. 3 . At this time, the main battery supplies power to the motor through the relay S1, and the auxiliary battery supplies power to the auxiliary equipment alone, and there is no electrical connection between the two;

When the vehicle brakes, the relay S1 is turned off and the relay S2 is turned on, as shown in FIG. 4 . At this time, due to the braking of the vehicle, the main battery does not need to supply power to the motor. At the same time, the motor works as a generator. The regenerative energy of the motor is recovered by the auxiliary battery through the relay S2, and supplies power to the auxiliary equipment. In addition, the relay S1 is turned off to cut off the electrical connection between the main battery and the motor, so as to ensure the feedback energy to charge the auxiliary battery.

Example:

The motor is a 3-phase permanent magnet brushless DC motor, the power battery is a lead-acid battery, and the power device of the drive controller is an electric bicycle with IGBT. The current direction at a certain moment of regenerative braking is shown in Figures 5 and 6.

In the figure, Ub1 represents the voltage of the main battery, Ub2 represents the voltage of the auxiliary battery, S1 and S2 are relays, VT1~6 represent the 6 power switches of the motor controller, and VD1~6 represent 6 diodes connected in antiparallel with the power switches.

At any moment when the vehicle is running, the on and off states of each power switch are determined by the position of the motor rotor at this time. Accompanying drawing 5 shows the current direction when the vehicle brakes and the power switch 4 is in the conduction state. At this time, due to the existence of the counter electromotive force of the rotor winding of the motor, the loop current rises; when the power switch 4 is turned off, due to the existence of the winding inductance, the diode VD1 is turned on, and the current direction is shown in Figure 7, and the auxiliary battery is charged through the switch S2 .

Claims (4)

1. an Electrical Bicycle energy regeneration accessory feed comprises motor, main storage battery, and main storage battery provides motor to move the required energy, and its voltage is pressed the configuration of motor rated voltage; Also comprise a boosting battery that is provided with in addition, it is characterized in that, boosting battery and accessory equipment direct connection, directly power to accessory equipment, auxiliary battery voltage is chosen by the accessory equipment operating voltage, also is connected with a driving governor between motor and main storage battery, and the driving governor power section is a three phase inverter bridge for permanent-magnet brushless DC electric machine, for the permanent magnet brush DC machine, its power section is a half-bridge structure; Main storage battery is connected by switch S 1 with driving governor, boosting battery is connected by switch S 2 with driving governor, according to car brakeing, normally move different running statees, shutoff and the conducting state of automatic switchover relay S1, relay S2, the electric energy that the motor regenerative brake is reclaimed charges to boosting battery by driving governor.

2. Electrical Bicycle energy regeneration accessory feed as claimed in claim 1, it is characterized in that described power device adopts power transistor GTR or metal-oxide-semiconductor field effect transistor MOSFET or insulated gate bipolar transistor IGBT or gate turn off thyristor GTO.

3. Electrical Bicycle energy regeneration accessory feed as claimed in claim 1 is characterized in that, described storage battery is lead-acid storage battery or lithium ion battery or nickel-hydrogen accumulator.

4. Electrical Bicycle energy regeneration accessory feed as claimed in claim 1 is characterized in that, described motor is permanent-magnet brushless DC electric machine or permanent magnet brush DC machine.

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