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The impact on inspiron 2500 battery performance analysis
The program design, in the monitoring module high-voltage circuit part of the normal work, as a result of the AD7888 consumes only the largest 3mW, OPAMP, isolation device power consumption is only a few mW, so the entire high-voltage power circuit power 50mW or less can be maintained, if the battery monitoring module high side voltage of 48V, then converted to high-voltage side current of only about 2mA. This is the battery at work at every turn dozens of A caused by the current power consumption term is almost negligible, very easy to make up for charging; as a result of high-pressure part of the power monitoring of each module are the same, at the same time high-pressure part of the electricity from the battery modules in series the total voltage, therefore monitoring of each battery module of the electricity load also are the same, high-pressure part of the check from the electric battery will not cause the consistency of bad, and in the circuit does not work, because of the isolation device PhotoMos Relay does not work in the worst-case leakage current through the greatest control and below 1mA for 6AH batteries, in the worst case of 10 years caused by self-discharge monitoring module additional capacity loss of only 1.46% (1e-6 × 24 × 365 × 10 / 6), far below the battery’s own self-discharge standard (usually better in the environment, the performance of the dell latitude c600 battery, dell latitude c610 battery self-discharge one year > 25%), therefore long-term use can be assured to meet the motor vehicle / car application required.
System performance
Voltage Detection: In the 20V full-scale such as the cases, the use of 12-bit A / D converter can be realized 4.9mV (20V/4096) resolution, the use of error correction can realize the measurement accuracy of better than 0.01V.
Temperature Detected: performance depends on the temperature sensor.
Advantages and disadvantages of the system structure as well as improved
The system has the following advantages: one, to achieve a higher sampling rate, because the expansion of the external ADC, the main factors affect the speed will only be concentrated in high-voltage signal conditioning circuit allows the signal bandwidth and ADC sampling rate, the current development of electronic technology so that the two can easily do more than 10kHz, which means latitude c640 battery that short-term test to more than 0.1ms instantaneous voltage changes, so measurable voltage change to the details, and data collection necessary to meet the battery. 2, As a result of the isolation measures voltage, high-pressure side of the impact of low-voltage side can be ignored. High-voltage and low-voltage complete isolation, the performance only depends on the device performance in isolation, such as the use of typical optocoupler such as the realization of DC up to 1000V isolation. 3, due to low pressure side and high side there is no contact, so it eliminates a huge (possibly up to several hundred volts) the impact of common-mode voltage, reducing the design more difficult.
