Journalists learned today from the Chinese car "leader" East Wind Pavilion ZT3000 laptop battery companies have found that, as China's earliest enterprises engaged in research and development of electric vehicles, one of its arm of Dongfeng Electric Vehicle Company building in eight years has made a series of achievements. Dongfeng Electric Vehicle project has been the industry's earliest known in China, the largest electric vehicle research and development, production and demonstration base of operations, and has become China's domestic industry leader in electric vehicles.
At present, the Dongfeng Electric Vehicle Company has mastered a variety of power control of hybrid technology, vehicle matching, vehicle testing and testing 337607-001 laptop battery technology, key technology and other assembly parts corresponding core technology of electric vehicles. At the same time, has formed a gas-electric hybrid buses, gas-electric hybrid buses, hybrid cars, hybrid power systems MPV four technology platforms, Dongfeng electric car company has to rely entirely on the results of China's independent research and development to achieve, especially hybrid electric vehicles powered vehicles industrialization.
According to reports, relying on electric cars built in Dongfeng Dongfeng Electric Vehicle Industry Park in 2008 to become China's first national patent industrialization pilot electric car base. Dongfeng Dongfeng hybrid city bus is independently developed by the 337607-003 laptop battery company in recent years, a key project of China's new energy future-oriented automotive market, a major product, is now the first in China to achieve volume production and sales. The Dongfeng own-brand cars based on the - Fengshen S30 platform, developed the first wind hybrid sedan has been basically completed, and can automatically shut down 398876-001 laptop battery roads through the city and quickly start to achieve 5-10% of the fuel-efficient rate . End
Figure 7 Principle of switched-capacitor charge balance
Switched-capacitor charge balance principle as shown in Figure 7, can be seen from the diagram, sequence switch driver circuit mainly by the clock circuits, which drive multi-channel switch the order of closure, the order of the lithium-ion laptop battery monomer access to transmission capacitor, through the transmission the imbalance between the energy of a single cell to achieve a balanced charging purposes. At the same time, by measuring the voltage on the capacitor sent to monitor every single cell voltage. If a single cell short-circuit fault occurs, low-voltage comparator output switches to prohibit signal, to prohibit access to short-circuit the laptop battery to send a single capacitor, to avoid affecting the normal work of other single cell at the same time to the constant-current constant-voltage PB992A converter into low-voltage laptop battery alarm signal, so that constant-current constant-voltage converter according to a single cell short-circuit conditions to determine the correct constant voltage. The biggest advantage of this balanced circuit is a waste of energy is very low, drawback is that the circuit complex, multi-way switch on-state resistance, high common-mode limit will affect the realization of a balanced charge. On the other hand, the parameter selection is difficult, for different power system configuration, circuit parameters required to the detailed design and verification, which is detrimental to the development cycle.
Four step-down converter equalizing charge
Figure 8 Principle of buck converter equalizing charge
Charging principles of a balanced buck converter as shown in Figure 8.
Buck converter is also a low-consumption balance charging solution for the balance of the program. It is very clear idea, the main circuit is a standard buck-type regulator in the energy storage inductor to add multiple sets of the same sub-windings, for single auxiliary laptop battery charge. Clearly, the low voltage single cell from the sub-windings get more energy, a high voltage to be less energy, so that the purpose of reaching a balanced charge. In order to obtain a good balance of effects, sub-windings of the consistency of the need for strict control. However, the consistency of inductor winding is very difficult to control, so this is such a control method of a biggest drawback. This study has just started charging, charging efficiency, balanced results, reliability analysis, the need for further in-depth study.
5 The average cell voltage balance charging
The average cell voltage balance charging principles as PB994A shown in Figure 9, Figure 1 only shows a single cell balance circuit, the other single cell is also equipped with an identical balanced circuit, which from a single laptop battery-powered amplifier.
Such a balanced charge control circuit of thought is: single-cell voltage and the average single cell voltage compared to control power switch to the laptop battery voltage is higher than the average voltage of the single-cell segregation. Therefore, all single cell voltage balancing under the effect of the circuit tends to the average cell voltage.
At first glance, this circuit is the open-loop control, in fact because of the role of the laptop battery internal resistance, a balanced circuit with a negative-feedback features in the closed-loop state. In order to prevent laptop battery discharge circuit in a balanced time work, you can lower power switching regulator diodes in series, so that the laptop battery discharge, the laptop battery voltage is low and the loss of shunt circuit.
The average cell voltage balance charging circuit model has in-depth study is considered the effect of a very good PB991A program. This circuit has been included in the LEO orbit lithium-ion laptop battery applications, the preferred program, has applied for patents in France and Europe.
No comments:
Post a Comment