Intelligent start-stop power generation integrated control makes the motorcycle more advanced

Abstract: In order to reduce exhaust emissions, start-stop technology has been popularized in automobiles. In response to increasingly stringent environmental regulations and market demands, ZLG has launched an integrated control solution for intelligent start-stop power generation for motorcycles, which has three major features: silent start, efficient charging and intelligent start-stop.

introduction

With the growth of consumption level, the number of motor vehicles is also growing explosively, and the resulting motor vehicle exhaust pollution problem is becoming more and more serious. In order to alleviate the exhaust emission problem of motor vehicles when waiting for traffic lights, traffic jams or short-term stops, start-stop technology has been widely used in automobiles. For motorcycles, the start-stop function is also on the agenda. The intelligent start-stop power generation integrated control solution launched by ZLG can give drivers a more comfortable feeling, reduce exhaust emissions, and save costs for motorcycle manufacturers!

Traditional motorcycle starter generator

The starter motor of a traditional motorcycle is a brushed DC motor, whose rotor is a coil connected to the outside through carbon brushes and commutators. This structure determines that it will generate excessive induced current and friction loss when rotating at high speed, making it unsuitable for use as a generator. Therefore, traditional motorcycles must be equipped with another magnetic motor to generate electricity. Take a certain model of scooter as an example, its structure is shown in the figure.

Figure 1 Traditional structure

The traditional starting method uses a brushed DC starter motor, which is connected to the main shaft of the gasoline engine through a one-way device and a reduction gear mechanism during starting. Starting process: The driver presses the ignition switch, the electrical system controls the starter motor to rotate, and the starter motor drives the gasoline engine to start. After the gasoline engine starts, the driver releases the ignition switch.

The traditional startup method has the following disadvantages:

Brushed DC motors have carbon brushes and commutators. The carbon brushes are easy to wear and produce sparks, causing carbon deposits on the commutator.

The one-way device and reduction gear mechanism are relatively complex and easy to be damaged.

Due to its connection mechanism, the traditional starter motor has obvious loud noise during the starting process.

The traditional power generation system consists of a magneto, a voltage-stabilizing rectifier and a battery. The battery of a motorcycle is only an auxiliary power source for the whole vehicle, and is generally only used when starting and the engine is stopped. The magneto is the main power source of the motorcycle. After the gasoline engine is started, it drives the magneto to rotate to generate electricity. Its functions include supplying power to the whole vehicle and charging the battery. The magneto is a brushless motor. The outer rotor is a magnet connected to the main shaft of the engine. The inner stator is a coil fixed to the engine housing. There is no mechanical contact between the stator and the rotor. The magneto generates alternating current, which requires a voltage-stabilizing rectifier to perform half-wave or full-wave rectification into direct current through a diode rectifier bridge. Due to the voltage drop of the diode, this method is generally inefficient.

Start-stop power generation integrated system

In the new integrated start-up and power generation system, the magneto in the traditional start-stop system is improved to a DC brushless motor with a Hall sensor, which can have both starting and power generation functions. In terms of mechanical structure, this system replaces the brushed DC starter motor and the traditional magneto, and does not require the original one-way device, reduction gear and other transmission parts, while retaining the advantage of the magneto without mechanical contact. In terms of electrical structure, the start-stop control and voltage stabilizing rectifier are integrated into an intelligent start-stop controller.

Figure 2 Start-stop power generation

The start-stop generator motor eliminates the brushless motor and its mechanical structure, and has the following advantages:

Simple structure and higher reliability;

No sparks, arcs or carbon powder is produced;

Reduce vehicle mass and assembly difficulty;

The brushless motor is maintenance-free and has no carbon brushes, so it has a low failure rate and low maintenance costs.

Intelligent start-stop power generation control solution

Based on years of accumulation of motor control technology, ZLG has launched a motorcycle intelligent start-stop power generation control solution for motorcycle start-stop power generation integrated systems.

Scope of application: Motorcycle start-stop generator integrated motor (magneto);

Control mode: Hall FOC vector control;

Simple mechanical structure, stable performance and long service life;

Silent starting technology eliminates the brushed starting motor and its mechanical structure;

Intelligent start-stop technology, comfortable and quick start;

High-efficiency charging technology, FOC vector control and magnetic weakening;

Constant current/constant voltage charging, complete charging monitoring function;

Complete software and hardware design reference;

Silent start technology means that when the motorcycle is started, there is no mechanical friction noise and motor current noise as in traditional motorcycles. The start-stop generator integrated motor is a brushless DC motor without a commutator, carbon brushes, or additional mechanical mechanisms. It is directly connected to the main shaft of the gasoline engine and does not produce mechanical friction noise when rotating. In terms of motor control, the solution uses Hall FOC vector control technology, which has small torque pulsation and large starting torque. In conjunction with the Hall sensor, precise closed-loop control can be achieved, and extremely fast starting can be achieved. From zero-speed acceleration to gasoline engine starting, the torque is stable throughout the process, eliminating current noise during startup.

Intelligent start-stop technology refers to a technology that allows the engine to automatically shut down when a motorcycle needs to stop temporarily for more than a certain period of time during driving. When it is necessary to continue moving forward, there is no need to press the start button again. Just release the brake and step on the accelerator to automatically start the engine. In the ZLG intelligent start-stop controller solution, the motorcycle speed signal, brake signal, throttle signal and engine temperature signal are collected, and the driver's intention is identified through intelligent logic to control the engine to shut down or start. When a traditional motorcycle stops for a short time, the engine is in an idling state. ZLG's intelligent start-stop technology allows the motorcycle to be in a shutdown state when it stops for a short time, reducing fuel consumption and exhaust emissions. Combined with silent and quick start technology, it brings a more comfortable experience to the driver.

In the design of the ZLG solution, the starting function and the charging function share the circuit, and the motor is controlled by software to start or generate electricity. After the gasoline engine is started, it drives the magnetic motor to generate charging current. The controller can achieve constant voltage and constant current output through FOC vector control and weak magnetic technology, and the charging current and voltage are controllable. The ZLG solution rectifies by switching MOS, which has lower losses and higher efficiency than the diode rectification of traditional voltage regulator rectifiers. Under high-speed rotation, the output voltage can be better stabilized through weak magnetic technology control.

Figure 3 Charging Function Block Diagram

in conclusion

Environmental regulations and drivers' comfort and convenience needs will drive the development of motorcycle start-stop technology. The intelligent start-stop power generation control solution launched by ZLG has three major features: silent start, intelligent start-stop and efficient charging. It can provide a complete software and hardware design reference to help manufacturers quickly realize productization.