Battery management system digital control quantity output method with diagnosis function

Abstract

The invention discloses a battery management system digital control quantity output method with a diagnosis function, which belongs to the field of battery pipeline systems, and has the following beneficial effects: the digital control quantity output by the main control of a battery management system is connected with one control pin of a relay; an intelligent high-side power switch chip BTT6200-4ESA is matched with a battery management system master control MCU chip to stably output digital control quantity to the relay, so that the method meets the stable control requirement of the relay of the battery system, and meanwhile, the method has the functions of diagnosing the state of a relay driving wire harness and diagnosing a digital control quantity output module of the battery management system; and on the premise that the basic control function of the battery management system on the relay can be met, the maintenance efficiency of relay components is improved, so that the reliability of a battery system product is improved.

Description

Technical Field

[0001] The invention belongs to the field of battery pipeline systems, and in particular relates to a digital control quantity output method of a battery management system with a diagnostic function. Background Art

[0002] With the development of the energy storage field, lithium-ion battery systems have been widely used in the energy storage field. As the matching battery management system has also developed rapidly, the battery management system has become more powerful and the requirements have become higher. In the existing technology of battery management control, the input quantity cannot be stabilized, resulting in poor relay control stability. At the same time, when the relay control is unstable, it is impossible to diagnose the relay status and the digital control quantity of the battery management system, which is not convenient for timely maintenance of the relay and leads to reduced reliability of the battery management system. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In order to overcome the shortcomings of the existing technology, a method for outputting digital control quantities of a battery management system with a diagnostic function is proposed to solve the problem that in the existing technology, the input quantity cannot be stabilized, resulting in poor stability of relay control. At the same time, when the relay control is unstable, the relay state and the digital control quantity of the battery management system cannot be diagnosed, which is not convenient for timely maintenance of the relay and leads to reduced reliability of the battery management system.

[0005] (II) Technical solution

[0006] The present invention is implemented by the following technical solution: The present invention proposes a digital control quantity output method for a battery management system with a diagnostic function, and its structure includes the following steps:

[0007] Step 1: Connect the two control pins of the relay, one to the negative pole of 24V, and the other to the digital control quantity output by the main control of the battery management system, that is, the high-side drive pin;

[0008] Step 2: Design a stable digital control quantity for relay output;

[0009] First, the battery management system main control MCU chip is connected through an intelligent high-side power switch chip to output digital control quantity to the outside. The intelligent high-side power switch chip adopts a chip of the BTT6200 series switch, and the model of the intelligent high-side power switch is BTT6200-4ESA.

[0010] Secondly, the peripheral circuit of the intelligent high-side power switch chip is designed, and the high and low level signals are output to the outside in combination with the MCU digital output pin to control the closing and disconnection of the relay. When the digital control quantity output by the battery management system is designed to be in a high level state, that is, the output is 24V positive, at this time, the relay control pin forms a current, thereby controlling the relay to close; when the digital control quantity output by the battery management system is designed to be in a low level state, that is, the output is 24V negative, at this time, the relay control pin cannot form a current, thereby controlling the relay to open;

[0011] Finally, the battery management system main control MCU is set to output externally through the chip, and the battery management system main control MCU chip PD6, PD12, MCU_HSD_IN2 and MCU_HSD_IN3 pins are respectively connected to the IN0, IN1, IN2 and IN3 of the intelligent high-side power switch chip, and the battery management system main control MCU is set to output externally through the chip, and the output pins are OUT0, OUT1, OUT2 and OUT3, so that the output pins have 1A driving capability and are directly used for relay control;

[0012] Step 3: Design the battery management system digital control harness status and digital output module status diagnosis;

[0013] First, the HSD_IS pin of the intelligent high-side power switch chip is connected to the current limiting resistor, voltage regulator and filter circuit, and then connected to the PF13 pin of the MCU, so that the main control MCU of the battery management system can perform signal detection;

[0014] Secondly, the OUT0, OUT1 and OUT2 pins of the intelligent high-side power switch chip are connected to the filter circuit, voltage regulator circuit and transistor, and then connected to the PD7, PD5 and PD10 pins of the MCU respectively, so that the main control MCU of the battery management system can perform signal control;

[0015] Finally, the PE10, PE8 and PC13 pins of the MCU chip are connected to the DEN, DSEL0 and DSEL1 pins of the intelligent high-side power switch chip through current-limiting resistors, so that the main control MCU of the battery management system can configure the intelligent high-side power switch chip;

[0016] Step 4: Set the battery management system digital control harness status and digital output module status diagnostic logic as follows;

[0017] First, the battery management system main control MCU configures the DEN, DSEL1, and DSEL0 states to control the output of each channel of the intelligent high-side power switch chip. ISThe order of the signals: if the states of DEN, DSEL1, and DSEL0 are all 0, no detection output is performed; if the states of DEN, DSEL1, and DSEL0 are 1, 0, and 0, channel 1 performs status detection and outputs I IS Signal; DEN, DSEL1, DSEL0 status is 1, 0, 1, then channel 2 performs status detection and outputs I IS Signal; DEN, DSEL1, DSEL0 status is 1, 1, 0, then channel 3 performs status detection and outputs I IS Signal;

[0018] Secondly, the main control MCU of the battery management system detects each input of the intelligent high-side power switch chip before receiving a high-level signal. IS state, and then detect each input of the intelligent high-side power switch chip to obtain a high-level signal. IS Status;

[0019] Finally, the current chip mode is confirmed before the high-level signal output by the MCU is obtained according to the input of the intelligent high-side power switch chip, and then the current chip mode is confirmed after the high-level signal output by the MCU is obtained according to the input of the intelligent high-side power switch chip. If the two modes are consistent, the mode state is output to the outside. If the two modes are inconsistent, the normal mode state is fixedly output, and the state of each channel is detected in turn according to a certain time period.

[0020] (III) Beneficial effects

[0021] One of the above technical solutions has the following advantages or beneficial effects:

[0022] In order to solve the problem that the input quantity cannot be stabilized in the prior art, resulting in poor relay control stability, and when the relay control is unstable, the relay state and the digital control quantity of the battery management system cannot be diagnosed, which is not convenient for timely maintenance of the relay and leads to reduced reliability of the battery management system, the digital control quantity output by the battery management system main control is connected to one of the control pins of the relay, and the digital control quantity of the relay output is stably output through the intelligent high-side power switch chip BTT6200-4ESA and the battery management system main control MCU chip, so that the method meets the stable control requirements of the battery system relay, and at the same time has the functions of relay drive harness state diagnosis and battery management system digital control quantity output module diagnosis, and on the premise of meeting the basic control function of the battery management system to the relay, the maintenance efficiency of the relay components is improved, thereby improving the reliability of the battery system product;

[0023] The present invention can diagnose the state of the digital control harness of the battery management system, and the harness state includes a normal state, a short circuit to 24V negative, a short circuit to 24V positive, and an open circuit state. The present invention can also diagnose the state of the digital output module of the battery management system, and the state of the digital output module includes a normal state and an over-temperature state. By diagnosing the state of the harness and the state of the digital module itself, timely alarms are issued to improve the use stability of the battery system relay. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0025] Figure 1 This is a structural schematic diagram of a method for outputting digital control quantities of a battery management system with a diagnostic function according to the present invention;

[0026] Figure 2 It is a structural schematic diagram of the present invention; DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

[0028] The present invention provides a method for outputting digital control quantity of a battery management system with a diagnostic function: comprising a relay, the relay having two control pins, one connected to a 24V negative, and the other connected to a digital control quantity outputted by a main control of the battery management system, i.e., a high-side drive pin;

[0029] 1. Design a stable digital control solution for relay output

[0030] Choose to use the chip BTT6200-4ESA with the battery management system main control MCU chip to output digital control quantity. The chip BTT6200-4ESA is an intelligent high-side power switch chip produced by Infineon. Design the peripheral circuit for this chip;

[0031] refer to Figure 1 , combined with the MCU digital output pin to output high and low level signals to the outside to control the closing and opening of the relay;

[0032] refer to Figure 2 and Figure 1 , Figure 2 The 5th, 6th, 141st, and 28th pins of the main MCU chip of the battery management system, namely the PD6, PD12, MCU_HSD_IN2, and MCU_HSD_IN3 pins, are connected to Figure 1The four inputs of the BTT6200-4ESA chip correspond to pins 2, 5, 9, and 10 of the BTT6200-4ESA chip, namely, pins IN0, IN1, IN2, and IN3. The main control MCU of the battery management system outputs to the outside through the chip. The output pins are pins 24, 20, 17, and 13, namely, pins OUT0, OUT1, OUT2, and OUT3. The output pins have a 1A driving capability and are directly used for relay control.

[0033] 2. Design the battery management system digital control harness status and digital output module status diagnosis

[0034] refer to Figure 1 and Figure 2 ,from Figure 1 It can be seen that the pin 7 of the chip BTT6200-4ESA is HSD_IS. This pin is connected to the current limiting resistor, voltage regulator and filter circuit and then connected to Figure 2 Pin 122 of the MCU, namely the PF13 pin of the MCU, enables the main control MCU of the battery management system to perform signal detection;

[0035] refer to Figure 1 and Figure 2 ,from Figure 1 It can be seen that the 24, 20, and 17 pins of the chip BTT6200-4ESA are digital control outputs, namely the OUT0, OUT1, and OUT2 pins of the chip BTT6200-4ESA. These pins are connected to the filter circuit, the voltage regulator circuit, and the transistor respectively. Figure 2 Pins 13, 16, and 18 of the MCU, namely the PD7, PD5, and PD10 pins of the MCU, enable the battery management system main control MCU to perform signal control.

[0036] refer to Figure 1 and Figure 2 , Figure 2 The 7th, 8th and 2nd pins of the MCU chip, namely the PE10, PE8 and PC13 pins of the MCU chip, are connected to the Figure 1 Pins 6, 8, and 11 of the BTT6200-4ESA chip, namely the DEN, DSEL0, and DSEL1 pins of the BTT6200-4ESA chip, enable the main control MCU of the battery management system to configure the BTT6200-4ESA chip;

[0037] 3. Design the battery management system digital control harness status and digital output module status diagnostic logic as follows:

[0038] In the first step, the main control MCU of the battery management system configures the status of DEN, DSEL1, and DSEL0, thereby controlling the chip BTT6200-4ES to output I IS The order of the signals is as shown in Table 1. If the states of DEN, DSEL1, and DSEL0 are all 0, no detection output is performed. If the states of DEN, DSEL1, and DSEL0 are 1, 0, and 0, channel 1 performs status detection and outputs I IS Signal; DEN, DSEL1, DSEL0 status is 1, 0, 1, then channel 2 performs status detection and outputs I IS Signal; DEN, DSEL1, DSEL0 status is 1, 1, 0, then channel 3 performs status detection and outputs I IS Signal;

[0039] Table 1: DEN, DSEL1, DSEL0 status matrix

[0040]

[0041] In the second step, the main control MCU of the battery management system detects each input of the chip BTT6200-4ESA before receiving a high-level signal. IS state, and then detect the chip BTT6200-4ESA each input to get a high level signal I IS To detect the open circuit state, the MCU_CH(n)_PU_ON pin of the MCU is required to control the transistor to pull up the output pin of the detected circuit of the chip BTT6200-4ESA.

[0042] The third step is to confirm the current chip mode based on the input of the chip BTT6200-4ESA before receiving the high-level signal output by the MCU, and then confirm the current chip mode based on the input of the chip BTT6200-4ESA after receiving the high-level signal output by the MCU. If the two modes are consistent, the mode state is output externally. If the two modes are inconsistent, the normal mode state is fixedly output;

[0043] For example, the first channel of chip BTT6200-4ESA, MCU configuration detection I IS(0) , then MCU outputs a low level to chip IN0, and then MCU detects I IS(0) Then, the current operation mode of the first channel is obtained by looking up the table according to the detection status value, as shown in Table 2 below; then the MCU outputs a high level to chip IN0, and the MCU detects I IS(0) Then, the current operation mode of the first channel is obtained by looking up the table according to the detection status value. If the two modes are the same, the current mode is output. If they are different, the normal mode is output. And the status of each channel is detected in turn according to a certain time period.

[0044] Table 2: Channel mode matrix

[0045]

[0046]

[0047] Among them, Normal operation is the normal state, Short circuit to GND is the short circuit to 24V negative state, Overtemperature is the chip module overtemperature state, Short circuit to VS is the short circuit to 24V positive state, Open load is the open circuit state; for each use condition, the judgment parameter value in the figure is different. For example, in the 1A drive current condition, GND is 0V, V S 24V, I IS(FAULT) The value is 6-35mA, V OL(OFF) is 20-22V, IL is the driving load current, take 1A; k ILIS Take 300, I IS(OL) When taking 33uA, the judgment criteria are as shown in Table 3;

[0048] Table 3: Status criteria (1A drive current)

[0049]

[0050]

[0051] Achieve stable output of digital control quantity to the relay, control the closing and opening of the relay, connect one of the control pins of the relay through the digital control quantity output by the main control of the battery management system, and stably output digital control quantity to the relay through the intelligent high-side power switch chip BTT6200-4ESA in cooperation with the main control MCU chip of the battery management system, so that this method meets the stable control requirements of the battery system relay, and at the same time has the functions of relay drive harness state diagnosis and battery management system digital control quantity output module diagnosis, and on the premise of meeting the basic control function of the battery management system to the relay, improve the maintenance efficiency of the relay components, thereby improving the reliability of the battery system product;

[0052] The present invention can diagnose the state of the digital control harness of the battery management system, which includes normal state, short circuit to 24V negative, short circuit to 24V positive and open circuit state. It can also diagnose the state of the digital output module of the battery management system, which includes normal state and over-temperature state. By diagnosing the state of the harness and the state of the digital module itself, timely alarm is given to improve the stability of the battery system relay.

[0053] Embodiment 2:

[0054] This embodiment uses an analog circuit to diagnose the state of the relay drive harness and the state of the digital control quantity output module. Compared with the first embodiment, it has the advantages of being able to achieve the same functions; the disadvantages are: the circuit finished product is relatively high, the stability deviation, and the failure rate is increased.

[0055] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0056] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for outputting digital control quantity of a battery management system with diagnostic function, characterized in that: The following steps are involved: Step 1: Connect the two control pins of the relay, one to the negative pole of 24V, and the other to the digital control quantity output by the main control of the battery management system; Step 2: Design a stable digital control quantity for relay output; First, the intelligent high-side power switch chip is connected to the main control MCU chip of the battery management system to output digital control quantities to the outside; Secondly, the peripheral circuit of the intelligent high-side power switch chip is designed, and the high and low level signals are output to the outside in combination with the MCU digital output pin to control the closing and opening of the relay; Finally, the PD6, PD12, MCU_HSD_IN2 and MCU_HSD_IN3 pins of the main control MCU chip of the battery management system are respectively connected to the IN0, IN1, IN2 and IN3 of the intelligent high-side power switch chip, and the main control MCU of the battery management system is set to output externally through the chip, which is directly used for the control of the relay; Step 3: Design the battery management system digital control harness status and digital output module status diagnosis; First, the HSD_IS pin of the intelligent high-side power switch chip is connected to the current limiting resistor, voltage regulator and filter circuit, and then connected to the PF13 pin of the MCU, so that the main control MCU of the battery management system can perform signal detection; Secondly, the OUT0, OUT1 and OUT2 pins of the intelligent high-side power switch chip are connected to the filter circuit, voltage regulator circuit and transistor, and then connected to the PD7, PD5 and PD10 pins of the MCU respectively, so that the main control MCU of the battery management system can perform signal control; Finally, the PE10, PE8 and PC13 pins of the MCU chip are connected to the DEN, DSEL0 and DSEL1 pins of the intelligent high-side power switch chip through current-limiting resistors, so that the main control MCU of the battery management system can configure the intelligent high-side power switch chip; Step 4: Set the battery management system digital control harness status and digital output module status diagnostic logic as follows; First, the battery management system main control MCU configures the DEN, DSEL1, and DSEL0 states to control the output of each channel of the intelligent high-side power switch chip. IS The order of the signals: if the states of DEN, DSEL1, and DSEL0 are all 0, no detection output is performed; if the states of DEN, DSEL1, and DSEL0 are 1, 0, and 0, channel 1 performs status detection and outputs I IS Signal; DEN, DSEL1, DSEL0 status is 1, 0, 1, then channel 2 performs status detection and outputs I IS Signal; DEN, DSEL1, DSEL0 status is 1, 1, 0, then channel 3 performs status detection and outputs I IS Signal; Secondly, the main control MCU of the battery management system detects each input of the intelligent high-side power switch chip before receiving a high-level signal. IS state, and then detect each input of the intelligent high-side power switch chip to obtain a high-level signal. IS Status; Finally, the current chip mode is confirmed before the high-level signal output by the MCU is obtained according to the input of the intelligent high-side power switch chip, and then the current chip mode is confirmed after the high-level signal output by the MCU is obtained according to the input of the intelligent high-side power switch chip. If the two modes are consistent, the mode state is output to the outside. If the two modes are inconsistent, the normal mode state is fixedly output, and the state of each channel is detected in turn according to a certain time period.

2. A method for outputting digital control quantity of a battery management system with diagnostic function according to claim 1, characterized in that: In the step 4, when detecting the disconnection state, the MCU_CH(n)_PU_ON pin of the MCU is required to control the transistor to pull up the output pin of the detected path of the intelligent high-side power switch chip.

3. The method for outputting digital control quantity of a battery management system with diagnostic function according to claim 1, characterized in that: The intelligent high-side power switch chip adopts the chip of the BTT6200 series switch.

4. A method for outputting digital control quantity of a battery management system with diagnostic function according to claim 3, characterized in that: The model of the intelligent high-side power switch is BTT6200-4ESA.

5. The method for outputting digital control quantity of a battery management system with diagnostic function according to claim 1, characterized in that: The MCU adopts the STM32MP series.

6. A method for outputting digital control quantity of a battery management system with diagnostic function according to claim 5, characterized in that: The model of the MCU is STM32MP15x.

7. The method for outputting digital control quantity of a battery management system with diagnostic function according to claim 1, characterized in that: In the step 2, the output pin of the battery management system main control MCU outputted to the outside through the chip has a 1A driving capability.

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