With the continuous development of social science and technology, the ecological environment we live in has been gradually destroyed, such as more and more serious haze, greenhouse effect and so on. Nowadays, our country advocates low-carbon travel. Our country spends a lot of financial and material resources to develop and use clean energy to gradually improve our living environment. Electric vehicles emerge as the times require. Its emergence and development are of great significance to change our way of life. Nowadays, the environmental protection problem of our country is becoming more and more serious, and the greenhouse effect caused by the exhaust of a large number of automobiles is becoming more and more serious.
So if we want to control this phenomenon to continue to deteriorate, we must find ways to replace these oil and diesel-burning automobiles with some green energy, control the re-emergence of haze phenomenon, and ensure our emptiness. Gas quality. Electric vehicle is the representative of the application of green energy, refers to the vehicle powered by on-board power supply and driven by stored electric energy, which meets the requirements of road traffic and safety regulations. Its structure is divided into several parts: electric drive and control system, driving force transmission and other mechanical systems, working devices to complete the tasks set. Because it does not produce polluted air tail gas in the process of use and uses clean energy, its development prospects are widely promising, but there are still many difficulties in current technology. The so-called motor controller is a kind of equipment used to control the operation of motor. Its function is generally realized by integrated circuit, not an independent device. Motor controller has the characteristics of maintenance-free, fast response and stable control of motor. Now it has been widely used in life and industry. Firstly, there are two bottlenecks in the development of electric vehicles. One is power battery, the other is power controller. At present, electric vehicles are all using AC motors, and the power of the car is provided by the storage battery on the vehicle. The battery can only provide DC power to the car, and the motor must require AC power. Simply speaking, it is necessary to change DC power into AC power to make the motor work and drive AC motor. Let’s make a further analysis of the phenomenon of electricity. The essence of electricity is actually a natural phenomenon, which is the movement of electrons.
Current refers to the directional movement of charged particles. In industry, electricity mostly refers to current.
Current is directional. At the load end, it is always from positive to negative, like running water, it is always from high to negative.
Low. Direct current means that the flow direction of current in conductor does not change with time, while the flow direction of alternating current in conductor changes alternately with time. In industry, the DC current we use shows a straight line on the time axis with a change of frequency of 0, and the AC current shows a change of sinusoidal wave on the time axis, meaning that the sinusoidal wave changes 50 times in a second and the frequency is 50 Hz. By converting direct current into alternating current, the motor is driven to rotate. The working principle of electric vehicle is not very complicated. The motor is used to drive the car forward, while the motor controller is used to drive the motor. The motor controller is mainly divided into two parts: controller and inverter. The motor controller receives the DC power and transmits its inversion into three-phase AC power to the motor controller. Then it transmits its power to the controller and feeds back to various instruments. Through the frequency rise and fall of the converter, the effect of the controller control is achieved. Motor controllers can be divided into three types according to the types of control motors: stepping motor controller, torque motor controller and DC motor controller. Stepper motor controller is an electronic product that sends out uniform pulse signal. The signal it sends enters the driver, converts into the strong current signal needed by the motor, and then drives the stepper motor to run. Its working principle is that it can accurately control the stepper motor to rotate every angle.
For every pulse received, the driver will send a pulse to the motor, making the motor rotate an angle.
Because of this characteristic, it is also widely used now. The working principle of the torque motor controller is to control the output torque and speed of the torque motor by superimposing high frequency oscillation signal with soft start and sawtooth wave.
The rotation principle of DC motor controller is that the conducting conductor moves under the force of magnetic field. The core index of DC motor is current commutation. The performance of commutation determines the performance of motor. It can also be classified into general motor controller, programmable motor controller and power-saving motor controller according to its functions. The programmable motor controller can control multiple stepping motors to operate separately. It uses computer programming language to carry out input, output, calculation, circulation, thermostatic element transfer, interruption and other instructions, and is widely used in various fields. Automation control field. The controller of power-saving motor is mainly realized by two technical ways, the design and improvement of motor body structure, the adoption of new materials and the improvement of external environment [2]. The development of electric vehicle controller includes the design of software and hardware. The core software is usually developed by the whole vehicle factory. The hardware and some parts can be provided by some parts manufacturers. At present, the technology of vehicle controller in foreign countries is relatively mature, and the technology of some old car manufacturers in the field of electric vehicles is relatively mature. Controller products are also relatively reliable through years of market testing. Many automotive parts manufacturers are also proposing technical solutions for vehicle controller in order to better apply the products, and then conduct a large number of research and development and production, formulate unified industry production standards, standardize our application technology, this way is a trend of controller development [3]. At present, our country is intensifying the research and development of electric vehicle controllers. By relying on universities and combining with the actual production situation of manufacturers, although we have preliminarily grasped the research and development and manufacturing capacity of vehicle controllers, the accumulation of technology is limited and the level is uneven. In terms of hardware, there is still a certain gap with foreign high-end technology products in many details, but the technology level can meet the basic needs of electric vehicles, product functions are relatively complete, has been applied to the prototype, and has the level of production and wholesale of small batches of products. A large part of the basic hardware and development tools of the controller also need to rely on imports, which is where our technical level and industrialization ability still need to be improved [4]. The application software can achieve the function realization, but the diagnosis function, security control strategy and monitoring function of some sudden situations need to be improved and optimized. At present, the chip integration capability is still relatively weak, and the manufacturing capability is really poor. Although the hardware structure design can be completed, the stability and reliability still have a long way to go. We need to constantly accumulate experience, improve our database, and improve the technical level of the hard power [5]. Electric vehicles will be widely used in the future, science and technology continue to update and develop, electric vehicle motor control system will also change with the occurrence, in-depth study of electric vehicle motor control system will effectively promote the rapid development of the electric vehicle industry. What we pursue is an environmentally friendly, efficient and low-cost way of travel. On the road of technology, we still need to go forward bravely and firmly.