CN211809175U - Battery inspection device and electric vehicle - Google Patents

Abstract

The application discloses battery inspection device and electric vehicle is applied to electric vehicle's electric drive system, and electric drive system includes driving motor and power supply unit, and power supply unit includes battery device, and battery device includes a plurality of parallel connection's monomer chain, and the monomer chain includes a plurality of series connection's battery monomer, and battery fault detection device includes a plurality of monomer detection circuitry. The number of the single detection circuits is matched with the number of the single batteries; the single detection circuit is arranged on the single battery and used for judging whether the single battery breaks down or not according to the output voltage of the single battery. Through judging that corresponding battery monomer breaks down, system or user just can make timely processing according to this trouble information to avoid battery device to take place serious trouble, and then can avoid electric vehicle unable normal work or even break down.

Description

Battery inspection device and electric vehicle

Technical Field

The present application relates to the field of automotive technology, and more particularly, to a battery inspection device and an electric vehicle.

Background

Vehicles such as automobiles and trains are land vehicles which run by taking an internal combustion engine, a steam engine, an electric motor and the like as power, and with the increase of the environmental protection pressure of human beings, the steam engine and the internal combustion engine can cause certain harm to the environment, so that the steam engine and the internal combustion engine are gradually replaced by the electric power, and particularly in the civil field, the application of the electric vehicles can make certain contribution to the improvement of the environment to a greater extent.

The electric automobile is a vehicle which takes a vehicle-mounted power supply as power and drives wheels to run by using a motor, and meets various requirements of road traffic and safety regulations. Because the influence on the environment is smaller than that of the traditional automobile, the prospect is widely seen, but the current technology is not mature and needs to be perfected in many aspects.

An electric vehicle generally includes at least a vehicle-mounted power supply device and a drive motor that operates under power supply from the power supply device. Because the required drive power of electric automobile is great, consequently, satisfying under the prerequisite of great high power, power supply unit needs great battery device, and present battery device is generally connected through the series-parallel connection mode by a plurality of battery monomers to satisfy the demand of electric automobile to drive voltage and power. In the working process of the battery device, due to the manufacturing quality and the working environment, a part of battery cells may break down, and if the battery cells cannot be detected in time, the whole battery device can be seriously broken down, so that the electric automobile cannot work normally or even is broken down.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present application provides a battery inspection apparatus and an electric vehicle, which are used for performing fault detection on a battery apparatus in an electric drive system of the electric vehicle to avoid serious faults of the battery apparatus caused by faults of one or some battery cells in the battery apparatus.

In order to achieve the above object, the following solutions are proposed:

a battery inspection device applied to an electric drive system of an electric vehicle, the electric drive system including a drive motor and a power supply apparatus, the power supply apparatus including a battery device, the battery device including a plurality of cell chains connected in parallel, the cell chains including a plurality of battery cells connected in series, the battery inspection device including a plurality of cell inspection circuits, wherein:

the number of the single detection circuits is matched with that of the single batteries;

the single detection circuit is arranged on the single battery and used for judging whether the single battery breaks down or not according to the output voltage of the single battery.

The single detection circuit comprises a voltage detection unit, a data transceiving unit and a fault judgment unit;

the voltage detection unit is used for detecting the output voltage of the battery cell as a first output voltage;

the data receiving unit is connected with the data receiving and transmitting units of other battery monomers through a data bus and used for receiving a plurality of output voltages of the other battery monomers as a plurality of second output voltages;

the failure determination unit is configured to determine that the battery cell has failed when an average value of the plurality of second output voltages does not match the first output voltage.

Optionally, each of the battery cells is provided with a cell cutting circuit, wherein:

the single cutting circuit is connected with the single detection circuit and used for cutting the battery single with the fault from the battery chain.

Optionally, the monomer cutting circuit includes a normally closed switch and a normally open switch, wherein:

the normally closed switch is connected with the battery monomer in series and used for being disconnected when the battery monomer breaks down;

the normally open switch is connected with the battery monomer and the normally closed switch which are connected in series in parallel and used for being closed when the battery monomer breaks down.

Optionally, the normally closed switch is linked with the normally open switch.

The driving motor comprises a rotor and a stator, a plurality of sets of driving coils are arranged on the stator, the power supply equipment is respectively connected with the plurality of sets of coils and used for simultaneously supplying power to the plurality of sets of driving coils or independently supplying power to a selected set of driving coils, each set of driving coil comprises a three-phase coil, and the wiring structure of the three-phase coil is star-shaped or triangular.

Optionally, the single-phase coil of each set of driving coils is an independent coil.

Optionally, the single-phase coil corresponding to each set of the driving coils is a different segment on a complete coil, and the leads at the two ends of the segment are the middle taps of the complete coil.

Optionally, the power supply apparatus includes a plurality of battery devices and a plurality of driving devices, wherein:

the battery device comprises a plurality of battery single cells, wherein the battery single cells are connected in series and parallel;

the electric energy input end of each driving device is respectively connected with the corresponding battery device, and the electric energy output end of each driving device is connected with the corresponding driving coil.

An electric vehicle comprising an electric drive system provided with a battery detection device as described above.

It can be seen from the above-mentioned technical scheme that this application discloses a battery inspection device and electric vehicle, is applied to electric vehicle's electric drive system, and electric drive system includes driving motor and power supply unit, power supply unit includes battery device, battery device includes a plurality of parallel connection's monomer chain, the monomer chain includes a plurality of series connection's battery monomer, battery fault detection device includes a plurality of monomer detection circuitry. The number of the single detection circuits is matched with that of the battery single bodies; the single detection circuit is arranged on the single battery and used for judging whether the single battery breaks down or not according to the output voltage of the single battery. Through judging that corresponding battery monomer breaks down, system or user just can make timely processing according to this trouble information to avoid battery device to take place serious trouble, and then can avoid electric vehicle unable normal work or even break down.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an embodiment of an electric drive system provided herein;

FIG. 1a is a schematic view of another structure of an electric drive system provided in the present application;

FIG. 1b is a schematic view of another structure of the electric drive system provided in the present application;

FIG. 2 is a schematic structural diagram of an embodiment of a battery inspection apparatus provided in the present application;

fig. 2a is a schematic structural diagram of a battery inspection apparatus provided in the present application;

fig. 2b is a schematic structural diagram of another battery inspection apparatus provided in the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The research and development of major scientific and technological projects of electric automobiles in China are started in 2001, and through two five-year planned scientific and technological passes and application pull of Olympic, Shibo and 'ten city thousand' demonstration platforms, the electric automobiles in China are in a continuous progress state from the inexistence to the existence, and a whole industry chain technical system of the electric automobiles with independent intellectual property rights is established.

Currently, in the technical routes of various electric vehicles, electric vehicles represented by hybrid electric vehicles, pure electric vehicles and fuel cell vehicles are generally considered as the main direction of the transformation development of the energy power system of the future vehicle, and have become the key points of the development of the automobile strong countries and the main automobile manufacturers in the world. China is already a large country in the world automobile industry, but China is large but not strong, and the automobile industry in the future of China must search for new ideas. The electric automobile industry is expected to develop a new growth point for the Chinese automobile industry.

From the perspective of foreign development, government support is very strong, although the construction of charging facilities in the major developed countries in foreign countries is still in the beginning. From the view of domestic development, the main participants of the construction of the Chinese charging facility include enterprises of national grid company, southern grid company, common-day sea oil, China petrochemical industry, BYD and the like. In recent years, China has already put a certain number of charging stations and charging piles into production, the charging modes include various modes such as quick charging, slow charging and battery changing, and the advanced work provides precious experience for subsequent construction. At present, enterprises such as national grid companies, southern grid companies, common-day marine oil enterprises, medium petrochemical enterprises and the like have signed strategic cooperation agreements with most local governments, and made clear construction targets and plans, and the construction of charging stations began to present a trend of accelerated development.

Automobile manufacturers famous in various countries around the world are all developing various electric automobiles and have made certain progress and breakthrough.

First, japan has been focusing on the development and development of electric vehicles for the purpose of energy crisis and environmental protection and for the purpose of occupying the future world automobile market. From the whole situation in the world, japan is one of the few countries in which the technology of electric vehicles is the fastest, and particularly, in terms of the product development of hybrid vehicles, japan is the leading position in the world. The enterprise, only two automotive companies, Toyota and Honda in Japan. In 1997, 12 months, toyota automotive first introduced the first mass-produced hybrid car PRIUS in the world on the japanese market. The car began exporting north america in 7 months of 2000 and exported to europe in 9 months of the same year, and has been marketed in more than 20 countries throughout the world. The products which are pushed out at present are second generation products after being improved for many times, and the production process is more mature. According to the test of Toyota automobile company, the PRIUS car saves 44.4% of oil compared with a corolla car with the same displacement under the urban working condition; the oil can be saved by 29.7% in suburbs and 40.5% comprehensively. Statistics show that Toyota motor companies have already gained 90% of the global hybrid vehicle market. In 2004, 9-15 days, the hybrid electric vehicle cooperation project signatory of the first automobile group and the japan Toyota automobile company in Beijing announced that both parties are within 2005. Jointly produce Toyota PRIUS hybrid power cars. The PRIUS hybrid car will enter the China market in the same year.

After the PRIUS hybrid cars, toyota corporation has also introduced ESTIMA hybrid cars and CROWN cars that carry a soft hybrid system. The Toyota automobile company has been at the forefront of the world in popularizing the low fuel consumption, low emissions, and improved ride performance of hybrid systems. Furthermore, the method is simple. Insight hybrid electric vehicles developed by Honda automotive corporation have also been marketed. In 2002, 4 months, Civic hybrid vehicles were released in the United states by Honda automotive company. Nissan automotive company announced that Ahima brand hybrid cars will be marketed to the United states in 2006, which was the first product to sign the Joint production hybrid vehicle agreement with Toyota automotive company in 2002.

Second, the united states. Automobile companies in the united states are inferior to those from japan in terms of electric automobile industrialization, and three major automobile companies have produced and sold pure electric automobiles only in small quantities, while hybrid and fuel cell electric automobiles have not been able to be industrialized, and hybrid electric automobiles from japan have taken a leading position in the us market.

Third, norway. The electric automobiles in Norway sell 1 million in 2012, and account for 5.2% of the new automobile sales in the same year, so that the electric automobiles in Norway attract attention to Norway with only 500 million people. Most of electric automobiles in Norwegian markets are of Leaf automobiles in daily products, the Leaf automobiles in 2012 are ranked 13 th in the Norwegian automobile sales market, and other brands of electric automobiles include Revas, KewetBudidies and the like.

Climate change, energy and environmental issues are long-standing problems that human society faces collectively. With the united states expressing the regression COP15 (united nations climate change framework convention) and the introduction of emerging countries typified by china and india into it, and the active implementation of energy and environmental protection strategies in major countries, the world has entered an era where the common problems of human society are really solved. The three problems of greenhouse gas emission, energy consumption and tail gas emission in the field of transportation are effectively solved, and the common problem of human beings which is directly influenced can be effectively solved, therefore, the governments, organizations, automobile manufacturers, energy suppliers and risk investment enterprises in the main world act together to promote the structure upgrade of the automobile industry in the world and the transformation of the power system electric strategy, promote the formation of the electric automobile social basic industry with a multi-layer structure and the construction of corresponding policies and organization guarantee systems, and promote the formation of the electric automobile society with sustainable development.

As an important force for world energy consumption and environmental protection, China actively implements the science and technology strategy of electric automobiles, promotes the upgrading of industrial structures and the electric transformation of power systems in the automobile industry, cultivates and develops the society of electric automobiles, and obtains certain effects, but still faces the problems of urgent need for perfection of policy and environment, weak industrial foundation, weak international competitiveness, poor environment of open cooperative innovation, low awareness of intellectual property protection and standardization, need to be strengthened in individual key technologies, high vehicle cost, insufficient exploration of business modes and the like. On the basis of briefly analyzing the current development situation and the stage characteristics of the foreign electric automobile society, the report emphatically summarizes the development process of the Chinese electric automobile society, forms the basic industrial structure characteristics of the Chinese electric automobile society, the current development situation of policies, standards and organization and guarantee systems required by the electric automobile society construction, and provides a suggestion for improving the development of the Chinese electric automobile society by combining with the strategic new industry cultivation and development of new energy automobiles.

The reduction of the greenhouse gas emission in the traffic field is an important means for solving global climate change and is a precondition for building a society for sustainable development of electric automobiles. The governments and organizations of main countries in the world set strict automobile exhaust emission standards, aiming at reducing the influence of the traffic field on the global climate and environment.

In addition, some events such as photochemical smog of los angeles in the united states, world petroleum crisis, movement disorder of the middle east, and Beijing haze weather put urgent demands on environmental protection and national petroleum safety, promote automobile technical progress in the world and accelerate social construction of electric automobiles.

As early as 2000, under the promotion of environmental protection and national petroleum safety strategy, the electric automobile society is built and proposed, and China enters the initial development stage of the 'science and technology guidance' of the electric automobile society. In the phase (the 'fifteen' period and the 'eleven-five' early period), the research and development of the key technology of the electric vehicle are taken as main characteristics, and a series of activities such as original innovation and system integration innovation of the key technology of the electric vehicle, test environment construction, professional technology talent culture, technical standard system construction, open collaborative innovation environment construction, scientific and technological achievement conversion activity and the like are intensively developed.

In the period of fifteen, the technology problem of the electric automobile is overcome as an entry point, the superiority of the social principle and system of the major works of China concentrated strength is brought into play by fully considering the current situations of weak foundation of China industry, weak scientific research strength, limited R & D investment of enterprises and the like, the strategic planning layout of the research and development of the electric automobile is creatively provided by the science and technology department, the key technology of the electric automobile is comprehensively deployed, and the original innovation and the system integration innovation of the key technology of the China electric automobile are completed. In the 'eleven-five' period, on the basis of seriously summarizing the early-stage research results, the research and development of a power system technology platform and key parts of the electric automobile are focused, and the attack and the customs of scale industrialization technology are strengthened.

The types of electric vehicles mainly include a pure electric vehicle (BEV), a hybrid electric vehicle (PHEV), and a fuel cell vehicle (FCEV).

The pure electric vehicle is a vehicle driven by a motor. Compared with a fuel automobile, the main differences are four parts: the device comprises a driving motor, a speed regulation controller, a power battery and a vehicle-mounted charger. The quality difference of the pure electric vehicle depends on the four large components, and the value of the pure electric vehicle also depends on the quality of the four large components. The application of the pure electric vehicle is directly related to the selection and the configuration of the four major components.

The speed per hour and the starting speed of the pure electric vehicle depend on the power and the performance of a driving motor, the length of the continuous mileage of the pure electric vehicle depends on the capacity of a vehicle-mounted power battery, the weight of the vehicle-mounted power battery depends on which power battery is selected, such as lead-acid, zinc carbon, lithium batteries and the like, the volume, the specific gravity, the specific power, the specific energy and the cycle life of the power battery are different, and the specific selection and the specific type of the battery depend on the positioning and the application of the manufacturer to the grade of the whole vehicle, the market definition and the market segmentation.

The driving motor of the pure electric automobile has a DC brush, a brushless, a permanent magnet and an electromagnetic part, and an AC stepping motor, and the selection of the driving motor is related to the configuration, the application and the grade of the whole automobile. In addition, the speed regulation control of the driving motor is divided into step speed regulation and stepless speed regulation, and the step speed regulation and the stepless speed regulation are divided into an electronic speed regulation controller and a non-speed regulation controller. The motor is provided with a hub motor, an inner rotor motor, a single motor drive, a multi-motor drive, a combined motor drive and the like.

The technology of the pure electric vehicle is relatively simple and mature, and the pure electric vehicle can be charged in places with power supply. However, there are some disadvantages, such as too little energy stored in the battery per unit weight, and the cost of the battery for the electric vehicle is expensive, and the cost of the battery is higher than that of the vehicle, and some of the batteries are only 1/3 of the vehicle, which depends on the life of the battery and the price of the oil and electricity in the local area.

A hybrid vehicle refers to a vehicle that is capable of deriving power from at least two types of on-board stored energy, a fuel-consuming engine and a rechargeable storage device, respectively. It can be divided into a Series Hybrid Electric Vehicle (SHEV), a Parallel Hybrid Electric Vehicle (PHEV), and a series-parallel hybrid electric vehicle (CHEV) according to the structural form of the power system.

The driving force of a series hybrid vehicle (SHEV) is derived from a hybrid of an electric motor. The structure is characterized in that the engine drives the generator to generate electricity, the electric energy is transmitted to the motor through the motor controller, and the motor drives the automobile to run. In addition, the power battery can also provide electric energy for the electric motor to drive the automobile to run.

The driving force of a Parallel Hybrid Electric Vehicle (PHEV) is supplied by an electric motor and an engine simultaneously or separately. The parallel driving system has the structural characteristics that the engine or the motor can be independently used as a power source, and the motor and the engine can be simultaneously used as the power source to drive the automobile to run.

The series-parallel hybrid electric vehicle (CHEV) has the characteristics of series and parallel driving modes. The structure can work in a series connection mixed mode and a parallel connection mixed mode, and simultaneously takes the advantages of the series connection mode and the parallel connection mode into consideration.

In addition, with the development of the technology of the hybrid electric vehicle, the types of the hybrid electric vehicle are not limited to the above types, and the hybrid electric vehicle may be divided into other types. At present, in the domestic market, the main stream of hybrid vehicles is gasoline hybrid, and in the international market, diesel hybrid vehicle models are developed quickly.

For a hybrid electric vehicle, the maximum power of an internal combustion engine can be determined according to the average required power after the hybrid electric vehicle is adopted, and the internal combustion engine works under the optimal working condition of low oil consumption and less pollution. When the power of the high-power internal combustion engine is insufficient, the power is supplemented by a battery; when the load is small, the surplus power can generate electricity to charge the battery, and the battery can be continuously charged due to the continuous work of the internal combustion engine, so the travel of the internal combustion engine is the same as that of a common automobile.

Because of the battery, the energy can be conveniently recovered when braking, downhill and idling. In a busy urban area, the internal combustion engine can be shut down and driven by a battery independently, so that zero emission of pollutants is realized. The internal combustion engine can conveniently solve the problems of air conditioning, heating, defrosting and other pure electric vehicles with large energy consumption. The existing gas station can be used for refueling without investment. The battery can be kept in a good working state, over-charge and over-discharge do not occur, the service life of the battery is prolonged, and the cost is reduced. The disadvantage is that the long distance high speed running can not save fuel basically.

The fuel cell is an automobile using the fuel cell as a power source. The chemical reaction process of the fuel cell does not produce harmful products, so the fuel cell vehicle is a pollution-free vehicle, and the energy conversion efficiency of the fuel cell is 2-3 times higher than that of an internal combustion engine, so the fuel cell vehicle is an ideal vehicle in the aspects of energy utilization and environmental protection.

The individual fuel cells must be combined into a fuel cell stack in order to obtain the necessary power to meet the requirements of the vehicle application.

In recent years, fuel cell technology has made significant progress. World famous automobile manufacturers, such as the company Daimler-Klisler, Ford, Toyota and general automobiles, have announced that fuel cell automobiles are projected to market before 2004. At present, fuel cell car sample vehicles are being tested and fuel cell powered transport buses are conducting demonstration projects in several cities in north america. There are still technical challenges in developing fuel cell vehicles, such as integration of fuel cell stacks, and the development of commercial electric vehicle fuel processors and auxiliary vehicle manufacturers is striving towards, and has made significant progress in, integrating components and reducing component costs.

Compared with the traditional automobile, the fuel cell automobile has the following advantages: zero or near zero emission; water pollution caused by engine oil leakage is reduced; the emission of greenhouse gases is reduced; the fuel economy is improved; the combustion efficiency of the engine is improved; the operation is stable and has no noise.

For any of the above electric vehicles, the basic components may include: an electric drive and control system, a mechanical system such as a drive transmission, a working device for performing a predetermined task, and the like. The electric drive and control system is the core of an electric automobile and is the biggest difference from an internal combustion engine automobile, and other devices of the electric automobile are basically the same as the internal combustion engine automobile. The electric driving and controlling system consists of driving motor, power source, motor speed regulating controller, etc.

The power supply provides electric energy for a driving motor of the electric automobile, and the electric motor converts the electric energy of the power supply into mechanical energy. The most widely used power source is the lead-acid storage battery, but with the development of the electric automobile technology, the lead-acid storage battery is gradually replaced by other storage batteries due to low energy, slow charging speed and short service life. The developing power supplies mainly comprise sodium-sulfur batteries, nickel-cadmium batteries, lithium batteries, fuel batteries and the like, and the application of the novel power supplies opens up a wide prospect for the development of electric automobiles.

As the most important component in an electric vehicle, its power battery performance determines its driving range and cost. The development work of batteries of electric vehicles goes through the development process from lead-acid batteries, nickel-metal hydride batteries to lithium batteries, and each battery has advantages and disadvantages.

The lead-acid battery is the earliest and the longest in use, and belongs to the storage battery series. The lead-acid battery has the best safety performance, rarely has the phenomena of explosion, ignition and the like, and only has a poor energy storage effect. Later, nickel-metal hydride batteries were developed, which have better effects on storing electric energy and power than lead-acid batteries, but since hydrogen generated during the charging process of the nickel-metal hydride batteries is easily exploded, enterprises have available and unavailable the nickel-metal hydride batteries.

By the year around 2000, people developed lithium batteries successfully. The electric energy stored by the lithium battery is 2-3 times that of the lead-acid battery, but because lithium ions contained in the lithium battery are activated on the surface of the metal layer, the lithium battery is easy to generate spontaneous combustion, explosion and other conditions in the air, and the danger is higher. Therefore, research and development of lithium batteries in various countries mainly control the safety and stability of the lithium batteries.

The lithium battery can be circularly charged for about 1000 times, wherein the energy storage effect of the lithium iron phosphate battery is poorer than that of a lithium cobaltate battery and a lithium manganate battery, but the lithium iron phosphate battery has the best safety performance and has much higher energy storage than that of a lead-acid battery, so the lithium iron phosphate battery is the best at present. The current power batteries include the following:

1) super capacitor

The super capacitor has the advantages of high mass specific power and long cycle life, and has the weaknesses of low mass specific energy and high purchase price, but the cycle life is as long as 50 ten thousand to 100 ten thousand, so that the single cycle price is not high, and the super capacitor can be connected with a lead-acid battery and an energy type lithium ion battery in parallel to form a power supply system with excellent performance.

2) Lead-acid battery

The lead-acid battery has mature production technology, good safety, low price and easy recovery and regeneration of waste batteries. In recent years, through a new technology, the defects that the specific energy is low, the cycle life is short, acid mist is generated during charging, lead possibly pollutes the environment during production and the like are continuously overcome, various indexes are greatly improved, and the lithium ion battery can be better used as a power supply of an electric bicycle and an electric motorcycle and can also play a good role on an electric automobile.

3) Lithium ion battery using lithium iron phosphate as anode

The lithium battery with the carbon as the negative electrode and the lithium iron phosphate as the positive electrode has the advantages of good comprehensive performance, higher safety, no expensive raw materials, no harmful elements, long cycle life up to 2000 times and overcoming the defect of low conductivity. The energy type battery has the mass specific energy up to 120Wh/kg, and can be used in parallel with the super capacitor to form a power supply with comprehensive performance. The power type mass specific energy is 70-80 Wh/kg, and the power type super capacitor can be used independently without being connected in parallel.

4) Lithium ion battery with lithium titanate as negative electrode

The volume change of lithium titanate is extremely small in charging-discharging, so that the stability of a motor mechanism and the long service life of a battery are ensured; the lithium titanate electrode point position is higher (1.5V relative to Li +/Li electrode), and lithium crystal branches can not be generated when the battery is charged, so that the high safety of the battery is ensured. However, the lithium titanate electrode potential is high, and even if the lithium titanate electrode potential is matched with a lithium manganate positive electrode with high electrode potential, the voltage of the battery is only about 2.2V, so the specific energy of the battery is only about 50-60 Wh/kg. Even so, the outstanding advantages of high safety and long service life of the battery are incomparable with other batteries.

The driving motor is used for converting electric energy of the power supply into mechanical energy and driving wheels and working devices through a transmission device or directly. However, the direct current motor has small power, low efficiency and large workload of maintenance due to the existence of commutation sparks; with the development of motor control technology, it is gradually replaced by direct current brushless motors (BLDCM), Switched Reluctance Motors (SRM) and alternating current asynchronous motors, such as a case-less disc-type axial field dc series motor.

According to the driving principle, the driving motors of the electric automobile can be divided into the following 4 types:

1) a direct current motor.

In the early development of electric vehicles, many electric vehicles adopt a direct current motor scheme. The direct current motor is characterized by mature product, easy control mode and excellent speed regulation. However, because the short plate of the direct current motor is very prominent, the complex mechanical structure (electric brush, mechanical commutator and the like) of the direct current motor restricts the instantaneous overload capacity and further improvement of the motor rotating speed; and under the condition of long-time work, the mechanical structure of the motor generates loss, and the maintenance cost is improved. In addition, when the motor runs, the rotor is heated by electric brush sparks, energy is wasted, heat dissipation is difficult, high-frequency electromagnetic interference is caused, and the factors affect the performance of the whole vehicle.

Because the defects of the direct current motor are very prominent, the direct current motor is already eliminated by the current electric automobile.

2) An AC asynchronous motor.

The asynchronous AC motor is widely used in industry, and features that the stator and rotor are made of laminated silicon steel sheets and are sealed by aluminium covers at both ends, and there is no mechanical part between stator and rotor. Compared with a direct-current motor with the same power, the alternating-current asynchronous motor has higher efficiency and lighter weight by about one half. If a vector control mode is adopted, controllability comparable to that of a direct current motor and a wider speed regulation range can be obtained. The alternating current asynchronous machine is the most widely applied motor on the high-power electric automobile at present due to the advantages of high efficiency, large specific power, suitability for high-speed operation and the like.

However, under the condition of high-speed operation, the rotor of the motor generates heat seriously, the motor is ensured to be cooled during working, meanwhile, a driving and controlling system of the asynchronous motor is very complicated, the cost of the motor body is higher, and in addition, a frequency converter is required to provide extra reactive power to establish a magnetic field during operation, so compared with a permanent magnet motor and a switched reluctance motor, the efficiency and the power density of the asynchronous motor are lower, and the asynchronous motor is not the choice for optimizing the energy efficiency.

A more common area where asynchronous motors are used is the united states, which is also artificially related to road conditions. In the united states, the highway has been of a certain scale, and vehicles generally continue to travel at a certain high speed except in large cities, so that asynchronous motors that can operate at high speeds and have higher efficiency at high speeds are widely used.

3) A permanent magnet motor.

The permanent magnet motor can be divided into two types according to the difference of the current waveform of the stator winding, one type is a brushless direct current motor which has rectangular pulse wave current; the other is a permanent magnet synchronous motor, which has a sine wave current. The two motors are basically the same in structure and working principle, the rotors are permanent magnets, loss caused by excitation is reduced, and the stator is provided with windings to generate torque through alternating current, so that the cooling is relatively easy. Because the motor does not need to be provided with an electric brush and a mechanical reversing structure, the motor does not generate reversing sparks during working, and has safe and reliable operation, convenient maintenance and higher energy utilization rate.

The control system of a permanent magnet motor is simpler than that of an ac asynchronous motor. However, due to the limitation of the permanent magnet material, under the conditions of high temperature, vibration and overcurrent, the permanent magnet of the rotor can generate demagnetization, so that the permanent magnet motor is easy to damage under relatively complicated working conditions, and therefore, the permanent magnet motor still needs to be developed and improved.

And the price of the permanent magnet material is higher, so the cost of the whole motor and a control system thereof is higher, and only China with abundant rare earth resources tends to use the driving scheme of the electric automobile of the permanent magnet motor at present. Like japan and europe, either a permanent magnet motor is made of a permanent magnet material of light rare earth, or a switched reluctance motor is directly used without a rare earth material, but has a higher requirement on the design of a controller.

4) A switched reluctance motor.

As a novel motor, compared with other types of driving motors, the switched reluctance motor has the simplest structure, the stator and the rotor are of a double-salient-pole structure formed by laminating common silicon steel sheets, the rotor is not provided with a winding, the stator is provided with a simple concentrated winding, and the switched reluctance motor has the advantages of simple and firm structure, high reliability, light weight, low cost, high efficiency, low temperature rise, easiness in maintenance and the like. And the motor has the excellent characteristic of good controllability of a direct current speed regulating system, is suitable for severe environment and is very suitable for being used as a driving motor of an electric automobile.

However, the switched reluctance motor has the characteristics of large torque fluctuation, need of a position detector and system nonlinearity, and has a magnetic field of jumping rotation, so that a control system is complex; generating a large pulse current for the DC power supply. In addition, the switched reluctance motor is of a double-salient-pole structure, torque fluctuation inevitably exists, and noise is the most important defect of the switched reluctance motor.

However, recent studies have shown that the noise of switched reluctance motors can be well suppressed using rational design, manufacturing and control techniques. Like the current research on the switched reluctance motor in japan, the switched reluctance motor produced by the japanese electricity is also widely applied to various industries such as electric vehicles, household appliances and the like. At present, manufacturers in China gradually pay attention to the future development direction of the driving motor of the electric automobile

The motor speed regulation control device is arranged for speed change, direction change and the like of the electric automobile, and is used for controlling the voltage or current of the motor to complete the control of the driving torque and the rotating direction of the motor.

In early electric vehicles, the speed of the dc motor was adjusted by connecting resistors in series or by changing the number of turns of the field winding of the motor. The speed regulation is staged, and additional energy consumption is generated or the structure of the motor is complex, so that the speed regulation is rarely adopted. The thyristor chopping speed regulation is widely applied, and the stepless speed regulation of the motor is realized by uniformly changing the terminal voltage of the motor and controlling the current of the motor. In the development of electronic power technology, it is gradually replaced by other chopping speed regulation devices of power transistors (such as GTO, MOSFET, BTR, IGBT and the like). From the development of the technology, along with the application of a novel driving motor, the application of the direct current inversion technology to the speed regulation control of the electric automobile becomes an inevitable trend.

In the rotation direction conversion control of the driving motor, the direct current motor changes the current direction of the armature or the magnetic field by means of the contactor to realize the rotation direction conversion of the motor, which makes the circuit complicated and reduces the reliability. When the AC asynchronous motor is used for driving, the change of the motor steering is only needed to change the phase sequence of the three-phase current of the magnetic field, so that the control circuit is simplified. In addition, the alternating current motor and the variable frequency speed regulation control technology thereof are adopted, so that the braking energy recovery control of the electric automobile is more convenient, and the control circuit is simpler.

The electric vehicle transmission functions to transmit the driving torque of an electric motor to a drive shaft of the vehicle, and most parts of the transmission are often omitted when the electric motor is used for driving. Because the electric motor can be started with load, the clutch of the traditional internal combustion engine automobile is not needed on the electric automobile. Because the rotation direction of the driving motor can be changed through circuit control, the electric automobile does not need reverse gear in the internal combustion engine automobile transmission. When the stepless speed regulation control of the motor is adopted, the electric automobile can omit the transmission of the traditional automobile. When the electric wheel drive is adopted, the electric automobile can also omit a differential mechanism of a traditional internal combustion engine automobile transmission system.

The running device has the function of changing the driving torque of the motor into acting force on the ground through the wheels to drive the wheels to run. It is the same as other vehicles, and is composed of wheel, tyre and suspension.

The steering device is arranged for realizing the turning of the automobile and comprises a steering engine, a steering wheel, a steering mechanism, steering wheels and the like. The control force acting on the steering wheel deflects the steering wheel by a certain angle through the steering engine and the steering mechanism, thereby realizing the steering of the automobile. Most electric vehicles are steered by front wheels, and electric forklifts used in industry are often steered by rear wheels. The steering device of the electric automobile is of a mechanical steering type, a hydraulic power steering type and the like.

The braking device of an electric vehicle is provided for decelerating or stopping the vehicle, like other vehicles, and generally comprises a brake and an operating device thereof.

An electromagnetic brake device is also commonly used in an electric vehicle, which can utilize a control circuit for driving a motor to realize the power generation operation of the motor, and convert the energy during deceleration braking into the current for charging a storage battery, thereby achieving the recycling. In a domestic electric automobile, a high-power passenger carrying automobile is provided with a endurance NAILI sliding vane type air compressor for providing air braking equipment, and the air braking mode is mainly a compressed air braking mode.

The working device is specially arranged for completing the operation requirement of an industrial electric automobile, such as a lifting device, a portal frame, a pallet fork and the like of an electric forklift. The raising of the forks and the tilting of the mast are typically accomplished by a hydraulic system driven by an electric motor.

As shown in fig. 1, the electric drive system provided by the present application is applied to an electric vehicle, and is used for replacing a conventional internal combustion engine to drive the electric vehicle to operate, and specifically comprises a drive motor and a power supply device.

The drive motor may be a dc drive motor or an ac drive motor, either of which includes a corresponding stator and rotor. The stator is used for receiving electric energy output by the power supply equipment to drive the rotor to rotate, and the rotor is driven by the stator to rotate and drives the electric automobile to operate.

Compared with the traditional motor, the driving motor in the application is different in that a plurality of sets of mutually independent driving coils are arranged in the stator, each set of driving coils can work under the driving of the electric energy output by the power supply equipment, and namely the electric energy output by the power supply equipment can be independently utilized to drive the rotor to rotate.

In this embodiment, the structure of the drive coils will be specifically described by taking 3 sets of drive coils as an example. Each set of drive coils includes three-phase coil L1, i.e., 3 single-phase coils, which are connected in a delta configuration or a star configuration, thereby constituting the above-described single set of drive coils.

For the plurality of sets of coils, the single-phase coil of each of the plurality of sets of drive coils is located at the same position in the stator. For example, three wires may be bundled together and wound into a single phase within the stator, with each of the three wires acting as a single phase coil for a corresponding drive coil. It is also possible to wind a single wire in the stator and then split the single pick wire into three parts by means of center tapping, as shown in fig. 1 a. The three independent single wires can be used for winding the corresponding single-phase coil, and the three independent single wires can be of a layered structure or other mixed structures.

The power supply device is used for supplying power to the driving motor, and specifically comprises a plurality of battery devices 10 and a plurality of driving devices 20, which are the same in number. The battery device can be called as a storage battery pack, and the storage battery pack used for driving the electric automobile at present is generally formed by a lithium battery monomer, because the lithium battery has many advantages compared with a lead storage battery, and has a considerable cost advantage along with the improvement of yield and technology.

The battery device generally includes a plurality of battery cells (not shown), where the battery cells may include a lithium battery cell or a group of lithium battery cells. The output voltage of the battery cells is generally not enough to drive the driving motor of the electric automobile to operate, so that the combination is performed in a series-parallel mode. The battery monomers can be connected in series to form a monomer chain, and the output voltage of each monomer chain can be matched with the driving voltage of the driving motor; and then connecting a plurality of monomer chains in parallel to meet the power requirement of the driving motor. Or a structure of firstly connecting in parallel and then connecting in series can be adopted.

The power supply device comprises a plurality of driving means, the number of which may be the same as the number of driving coils described above, i.e. one set of driving coils corresponds to one driving means, as shown in fig. 1 b. The electric energy input end of each driving device is respectively connected with the battery device, namely the electric energy input end of each driving device can receive the electric energy output by the battery device; the power output ends of the driving devices are connected with the driving coils, namely each driving device is connected with the corresponding driving coil.

All the drive coils can be simultaneously powered by controlling the driving device, and power can also be supplied to a selected set of drive coils, namely all or part of the drive coils of the drive motor are enabled to work by controlling the switch of the driving device. Both can the independent work of each set of drive coil, even partial drive coil damage can not influence the work of driving motor yet.

The power supply device further includes a charging module (not shown) for charging the battery device, the power source of the charging module is generally a charging pile, the battery device is charged after receiving the input electric energy from the charging pile, that is, all the battery cells of the battery device are charged simultaneously, so that the charging module requires a large charging current. The charging module can also be composed of a plurality of charging units, each charging unit is used for charging one single battery, and the load sharing of the charging units can reduce the overall load pressure of the charging module. Each charging unit also charges several battery cells, that is, the number of the charging units may not be equal to the number of the battery cells.

Example one

Fig. 2 is a schematic structural diagram of an embodiment of a battery inspection apparatus provided in the present application.

As shown in fig. 2, the battery inspection apparatus provided in the present embodiment is used for detecting a failure of a battery device in an electric drive system. The electric drive system has been described in detail in the above embodiments, and is not described herein again, and the battery device of the system includes a plurality of parallel cell chains, and each cell chain is composed of a plurality of series-connected battery cells B.

The battery detection device comprises a plurality of single detection circuits, the number of the single detection circuits 30 is the same as that of the single batteries, namely, one single detection circuit is arranged on each single battery, and the single detection circuits are connected through a data bus 40. Because the output voltage of the battery cell is abnormal when the battery cell fails, whether the battery cell fails or not is judged by detecting the output voltage of the corresponding battery cell.

Generally, the output voltage of the battery cell becomes smaller with the discharge time of the battery, which is also a method for detecting the remaining capacity of the battery cell, but the battery cell may have a process difference to cause a difference in the output voltage, but the difference may be small. In view of this, the cell detection circuit includes a voltage detection unit 31, a data transceiving unit 32, and a failure determination unit 33, as shown in fig. 2 a.

The voltage detection unit is used for detecting the output voltage of the battery cell, wherein the output voltage is described as a first output voltage; the data transceiver unit is connected with the data transceiver units of other single body detection circuits through a data bus, the output voltages of other single bodies of batteries are received through the data bus, the output voltages are described as second output voltages, and the second output voltages are also multiple because the other single bodies of batteries are multiple; the fault determination unit firstly obtains an average voltage according to the plurality of second output voltages, then determines whether the first output voltage is matched with the average voltage, namely whether the difference value of the first output voltage and the average voltage is within an allowable range, wherein the range can be determined in advance according to specific engineering parameters of the single battery, if the first output voltage and the average voltage are not matched with each other, the single battery is determined to have a fault, otherwise, the single battery is in a normal state.

It can be seen from the above technical solution that this embodiment provides a battery inspection device of an electric drive system, the electric drive system is applied to an electric vehicle, and includes a driving motor and a power supply device, the power supply device includes a battery device, the battery device includes a plurality of parallel connection's monomer chain, the monomer chain includes a plurality of series connection's battery monomer, battery detection device includes a plurality of monomer detection circuit. The number of the single detection circuits is matched with that of the battery single bodies; the single detection circuit is arranged on the single battery and used for judging whether the single battery breaks down or not according to the output voltage of the single battery. Through judging that corresponding battery monomer breaks down, system or user just can make timely processing according to this trouble information to avoid battery device to take place serious trouble, and then can avoid electric vehicle unable normal work or even break down.

The battery cell in this embodiment is further provided with a cell cutting circuit, and the circuit is used for cutting the battery cell with a fault from the battery device. The cell cutting circuit specifically includes a normally closed switch K1 and a normally open switch K2, as shown in fig. 2b, and control devices of the two switches are connected to the cell detection circuit, and are used for controlling the two switches according to a fault signal indicating that the battery cell has a fault.

The normally closed switch is connected with the battery monomer in series to form a small power supply branch, the normally open switch is connected with the power supply branch in parallel, and the battery monomer is connected to a monomer chain through the normally closed switch under the normal state and normally serves as a working unit of the battery device; when monomer detection circuitry exports above-mentioned fault signal, normally closed switch opens, stops this free work of battery, and normally open switch is closed simultaneously, guarantees the complete of battery chain, can avoid a plurality of free inefficacys of battery promptly.

In order to ensure the cooperative work of the normally open switch and the normally closed switch, the two switches are in linkage action, and the normally open contact and the normally closed contact of one switch element can be used as the normally open switch and the normally closed switch during specific implementation.

Example two

The present embodiment provides an electric vehicle provided with the electric drive system provided in the above embodiment, which includes a drive motor and a power supply apparatus. The driving motor comprises a rotor and a stator, and a plurality of sets of driving coils are arranged on the stator; the power supply equipment is respectively connected with the plurality of sets of coils and is used for simultaneously supplying power to the plurality of sets of driving coils or independently supplying power to a selected set of the driving coils. And the power supply apparatus includes a battery device provided with the battery detection device provided in the above embodiment, for checking a failure of the battery device. By the arrangement, each drive coil in the plurality of drive coils can work independently, and other drive coils can drive the rotor to work when a part of the drive coils have faults. The problem that the electric automobile cannot run due to partial failure of the driving coil can be avoided under the environment with high reliability, such as the application of the electric automobile.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (9)

1. A battery inspection device applied to an electric drive system of an electric vehicle, the electric drive system including a drive motor and a power supply apparatus, the power supply apparatus including a battery device, the battery device including a plurality of cell chains connected in parallel, the cell chains including a plurality of battery cells connected in series, characterized in that the battery inspection device includes a plurality of cell detection circuits, wherein:

the number of the single detection circuits is matched with that of the single batteries;

the single detection circuit is arranged on the single battery and used for judging whether the single battery fails according to the output voltage of the single battery;

the single detection circuit comprises a voltage detection unit, a data transceiving unit and a fault judgment unit;

the voltage detection unit is used for detecting the output voltage of the battery cell as a first output voltage;

the data receiving and transmitting unit is connected with the data receiving and transmitting units of other battery monomers through a data bus and used for receiving a plurality of output voltages of the other battery monomers as a plurality of second output voltages;

the failure determination unit is configured to determine that the battery cell has failed when an average value of the plurality of second output voltages does not match the first output voltage.

2. The battery inspection apparatus of claim 1, wherein a cell cut-off circuit is provided on each of the battery cells, wherein:

the monomer cutting circuit is connected with the monomer detection circuit and used for cutting the battery monomer with a fault from the monomer chain.

3. The battery inspection apparatus of claim 2, wherein the cell cut-out circuit comprises a normally closed switch and a normally open switch, wherein:

the normally closed switch is connected with the battery monomer in series and used for being disconnected when the battery monomer breaks down;

the normally open switch is connected with the battery monomer and the normally closed switch which are connected in series in parallel and used for being closed when the battery monomer breaks down.

4. The battery inspection apparatus of claim 3, wherein the normally closed switch is linked with the normally open switch.

5. The battery inspection apparatus according to claim 1, wherein the driving motor includes a rotor and a stator, the stator having a plurality of sets of driving coils disposed thereon, and the power supply devices are respectively connected to the plurality of sets of driving coils for supplying power to the plurality of sets of driving coils simultaneously or individually to a selected one of the sets of driving coils;

each set of driving coils comprises a three-phase coil, and the wiring structure of the three-phase coil is star-shaped or triangular.

6. The battery inspection apparatus of claim 5, wherein the corresponding single phase coil of each set of drive coils is an independent coil.

7. The battery inspection apparatus of claim 5, wherein the corresponding single phase coils of each set of the drive coils are different segments of a complete coil, and the leads at the two ends of the segments are center taps of the complete coil.

8. The battery inspection apparatus according to claim 5, wherein the power supply device includes a plurality of battery means and a plurality of driving means, wherein:

the battery device comprises a plurality of battery single cells, wherein the battery single cells are connected in series and parallel;

the electric energy input end of each driving device is respectively connected with the corresponding battery device, and the electric energy output end of each driving device is connected with the corresponding driving coil.

9. An electric vehicle comprising an electric drive system, characterized in that the electric drive system is provided with the battery inspection device according to any one of claims 1 to 8.

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