Battery cell voltage sampling and equalization time-sharing control circuit

Abstract

The application discloses a novel battery monomer voltage sampling and equalization time-sharing control circuit, which comprises a monomer sampling and equalization circuit, a time-sharing signal generating circuit and a time-sharing control circuit; a positive electrode of a battery monomer B1 is connected with a positive input end of an operational amplifier U1, a negative electrode of the battery monomer B1 is connected with a negative input end of the operational amplifier U1, the operational amplifier U1 outputs an amplified signal to a multi-way selection switch U2, a microprocessor U4 respectively outputs an analog channel selection signal to the multi-way selection switch U2 and a decoder U3; the decoder U3 judges whether to output a first time-sharing control signal to the time-sharing control circuit according to the need of voltage sampling, so as to realize the voltage sampling function of the battery monomer B1, the microprocessor U4 judges whether to output a second time-sharing control signal to the time-sharing control circuit according to the need of equalization time-sharing control, so as to realize the equalization time-sharing control function, and the application realizes the functions of battery monomer voltage sampling and equalization time-sharing control.

Description

TECHNICAL FIELD

[0001] The application relates to a battery cell voltage sampling and equalization time-sharing control technology used on a satellite. BACKGROUND

[0002] A lithium ion battery pack used on a satellite generally adopts a multi-section series connection mode to realize a required bus voltage, but due to the differences in the characteristics of battery cells constituting the lithium ion battery pack and the power consumption of a cell sampling circuit, voltage differences exist among the cells and gradually expand, and after multiple charging and discharging cycles in orbit, the battery cells may be overcharged, thereby affecting the safety of the satellite.

[0003] To avoid the above situation, the current general method is to separately lead out a sampling line and an equalization line from the positive end of the battery cell, and meanwhile, the equalization positive line of the next stage battery cell positive end is used as the equalization return line of the previous stage battery cell negative end. The design method has certain limitations, and in the process of equalization control, the collected battery cell voltage has a certain deviation from the actual value. In addition, the more the number of series connection, the more the number of wires used, and more connector points need to be occupied, and the wire harness needs to be specially designed for heat dissipation, which all increase the cost and weight.

[0004] Therefore, a circuit needs to be designed to realize the time-sharing control of battery pack cell sampling and equalization, and to realize the equalization control of multiple battery cells at the same time. SUMMARY

[0005] In view of the deficiencies in the prior art, the application provides a novel battery cell voltage sampling and equalization time-sharing control circuit, which is simple and reliable, realizes stable sampling of the battery cell voltage, realizes time-sharing control of sampling and equalization, has high integration, saves cable and connector resources, and can be functionally expanded according to different requirements.

[0006] To achieve the above object, the application provides the following technical scheme:

[0007] The novel battery cell voltage sampling and equalization time-sharing control circuit comprises a cell sampling and equalization circuit, a time-sharing signal generating circuit and a time-sharing control circuit; the cell sampling and equalization circuit comprises an operational amplifier U1; the time-sharing signal generating circuit comprises a multi-way selection switch U2, a decoder U3 and a microprocessor U4; the positive pole of a battery cell B1 is connected with the positive input end of the operational amplifier U1, and the negative pole of the battery cell B1 is connected with the negative input end of the operational amplifier U1; the operational amplifier U1 outputs the amplified signal to the multi-way selection switch U2; the microprocessor U4 outputs an analog channel selection signal to the multi-way selection switch U2 and the decoder U3 respectively; the decoder U3 judges whether to output a first time-sharing control signal to the time-sharing control circuit according to the voltage sampling requirement, thereby realizing the voltage sampling function of the battery cell B1; and the microprocessor U4 judges whether to output a second time-sharing control signal to the time-sharing control circuit according to the equalization time-sharing control requirement, thereby realizing the equalization time-sharing control function.

[0008] As a further scheme of the application, the cell sampling and equalization circuit further comprises an equalization power switch tube V1, and the time-sharing control circuit comprises an RS flip-flop U5, an NPN transistor V2, a PNP transistor V3 and an NPN transistor V4; when the equalization condition is not met, the microprocessor U4 does not output the second time-sharing control signal, the PNP transistor V3 is in the conducting state, the E and S pins of the RS flip-flop U5 are in the low level, the output end Q is in the high resistance state, the NPN transistor V2 is in the off state, and the equalization power switch tube V1 is in the off state.

[0009] As a further scheme of the application, when the equalization condition is met, the microprocessor U4 outputs the second time-sharing control signal, the PNP transistor V3 is in the off state, if the battery cell B1 voltage is not sampled at this time, the NPN transistor V4 remains in the off state, the E and S pins of the RS flip-flop U5 are in the high level, the output end Q is in the high level, the NPN transistor V2 is in the conducting state, and the equalization power switch tube V1 is in the conducting state, thereby starting the equalization control function.

[0010] As a further scheme of the application, if the battery cell B1 voltage is sampled at this time, the microprocessor U4 outputs the analog channel selection signal, the decoder U3 outputs the first time-sharing control signal to the outside, which is in the high level, the NPN transistor V4 changes from the off state to the conducting state, the E and S pins of the RS flip-flop U5 change from the high level to the low level, the output end Q changes from the high level to the high resistance state, the NPN transistor V2 changes from the conducting state to the off state, thereby controlling the equalization power switch tube V1 to be in the off state, and thereby realizing the stable sampling function of the battery cell voltage.

[0011] As a further scheme of the present application, when the battery monomer B1 voltage sampling is completed, the first time-sharing control signal outputted by the decoder U3 disappears, the NPN transistor V4 changes from conducting to off state, the E and S pins of the RS flip-flop U5 change from low level to high level, the output pin Q changes from high resistance to high level, the NPN transistor V2 changes from off to conducting state, and the equalization power switch V1 is re-conducted to continue equalization.

[0012] As a further scheme of the present application, the positive electrode of the battery monomer B1 is divided by R3 and R5 and then inputted to the positive input terminal of the operational amplifier U1, and the negative electrode of the battery monomer B1 is divided by R6 and R4 and then inputted to the negative input terminal of the operational amplifier U1.

[0013] As a further scheme of the present application, the analog channel selection signal outputted by the microprocessor U4 is TMCH0, TMCH1, TMCH2 and TMCH3.

[0014] As a further scheme of the present application, the first time-sharing control signal outputted by the decoder U3 is equalization shielding signal, and the second time-sharing control signal outputted by the microprocessor U4 is equalization signal.

[0015] The present application has the following beneficial effects:

[0016] The present application uses the signal outputted by the microprocessor as the selection signal of the multi-way selection switch and the input signal of the decoder, and then generates time-sharing signal, so as to realize the time-sharing control function of the battery monomer voltage sampling and equalization, support the equalization control of multiple battery monomers at the same time, and not affect the voltage sampling signal.

[0017] In order to more clearly illustrate the structural features and effects of the present application, the present application will be described in detail below with reference to the drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is the battery monomer voltage sampling and equalization time-sharing control circuit of the present application.

[0019] Figure 2 It is the monomer sampling and equalization circuit of the present application.

[0020] Figure 3 It is the time-sharing signal generation circuit of the present application.

[0021] Figure 4 It is the time-sharing control circuit of the present application. DETAILED DESCRIPTION

[0022] The application will be further described in connection with the drawings and relevant knowledge, and be clearly and completely described, obviously, the described application is only a part of the embodiments of the application, rather than all the embodiments.

[0023] Referring to Figures 1-4 As shown in the figure, the application provides a new battery cell voltage sampling and equalization time-sharing control circuit, which solves the certain limitations in the design of the prior art, and has a certain deviation in the collected battery cell voltage compared with the actual value in the process of equalization control. In addition, the more the number of series is, the more the number of wires is, and more connector contacts need to be occupied, and the wire harness needs to be specially designed for heat dissipation, which will increase the cost and weight.

[0024] The specific technical scheme includes a cell sampling and equalization circuit, a time-sharing signal generating circuit, and a time-sharing control circuit; the cell sampling and equalization circuit includes an operational amplifier U1;

[0025] The time-sharing signal generating circuit includes a multiplexing switch U2, a decoder U3, and a microprocessor U4; the positive electrode of the battery cell B1 is connected with the positive input end of the operational amplifier U1, the negative electrode of the battery cell B1 is connected with the negative input end of the operational amplifier U1, the operational amplifier U1 outputs the amplified signal to the multiplexing switch U2, and the microprocessor U4 outputs an analog channel selection signal to the multiplexing switch U2 and the decoder U3; the decoder U3 judges whether to output a first time-sharing control signal to the time-sharing control circuit according to the need of voltage sampling, so as to realize the voltage sampling function of the battery cell B1, and the microprocessor U4 judges whether to output a second time-sharing control signal to the time-sharing control circuit according to the need of equalization time-sharing control, so as to realize the equalization time-sharing control function. Figure 1 As shown in the figure, the application realizes the functions of battery cell voltage sampling and equalization time-sharing control through the design of the cell sampling and equalization circuit, the time-sharing signal generating circuit, and the time-sharing control circuit, and the signal output by the microprocessor is used as the selection signal of the multiplexing switch and the input signal of the decoder, and then the time-sharing signal is generated.

[0026] In the application, referring to Figure 1 As shown in the figure, B1 is a battery cell, V1 is an equalization power switch tube, R1 is an equalization power resistor, and R2 is a power switch tube gate limiting resistor. The positive electrode of B1 is input to the positive input end of the operational amplifier U1 after being divided by R3 and R5, the negative electrode of B1 is input to the negative input end of the operational amplifier U1 after being divided by R6 and R4, and the operational amplifier outputs to the multiplexing switch U2 of the time-sharing signal generating circuit after amplification, wherein the multiplexing switch U2 is a 16-1 multiplexing switch, and is specifically connected to the 9th pin of the multiplexing switch U2.

[0027] Referring toFigure 2 As shown, the microprocessor U4 outputs analog channel selection signals, including TMCH0, TMCH1, TMCH2 and TMCH3, to select the channel to be collected, and the signals are output from the first pin of the multi-channel selection switch U2. Meanwhile, the analog channel selection signals output by the microprocessor U4 are also input signals of the decoder U3, wherein the decoder U3 is a 4-16 decoder, and the decoder U3 outputs a first time-sharing control signal, which is an equalization shielding signal. Meanwhile, the microprocessor U4 outputs a second time-sharing control signal, which is an equalization signal.

[0028] Referring to Figures 2-4 As shown, the single-cell sampling and equalization circuit further includes an equalization power switch V1, and the time-sharing control circuit includes an RS flip-flop U5, an NPN transistor V2, a PNP transistor V3 and an NPN transistor V4. When the equalization condition is not met, the microprocessor U4 does not output the second time-sharing control signal, the PNP transistor V3 is in a conducting state, the E and S pins of the RS flip-flop U5 are both at a low level, the output end Q of the RS flip-flop U5 is in a high resistance state, the NPN transistor V2 is in a cut-off state, and the equalization power switch V1 is in a cut-off state.

[0029] Further, referring to Figure 4 As shown, when the equalization condition is met, the microprocessor U4 outputs the second time-sharing control signal, so that the PNP transistor V3 is in an off state. If the single-cell voltage of the battery is not sampled at this time, the NPN transistor V4 remains in a cut-off state, the E and S pins of the RS flip-flop U5 are both at a high level, the output end Q of the RS flip-flop U5 is at a high level, so that the NPN transistor V2 is in a conducting state, and the equalization power switch V1 is further controlled to be in a conducting state, thereby enabling the equalization control function.

[0030] If the single-cell voltage of the battery is sampled at this time, the microprocessor U4 outputs the analog channel selection signal, the decoder U3 outputs the first time-sharing control signal, which is at a high level, the NPN transistor V4 changes from an off state to a conducting state, the E and S pins of the RS flip-flop U5 change from a high level to a low level, the output end Q of the RS flip-flop U5 changes from a high level to a high resistance state, so that the NPN transistor V2 changes from a conducting state to a cut-off state, and the equalization power switch V1 is further controlled to be in a cut-off state, thereby completing the stable sampling function of the single-cell voltage of the battery.

[0031] In the application, when the battery cell voltage sampling is completed, the first time-sharing control signal outputted by the decoder U3 disappears, the NPN transistor V4 changes from on to off, the E and S pins of the RS flip-flop U5 change from low to high, the output pin Q of the RS flip-flop U5 changes from high resistance to high, the NPN transistor V2 changes from off to on, and the equalization power switch V1 is re-conducted to continue the equalization, thereby realizing the time-sharing control function of the battery cell voltage sampling and equalization.

[0032] Through the above-mentioned circuit design, the application is simple and reliable, realizes the stable sampling of the battery cell voltage, realizes the time-sharing control of the sampling and equalization, has high integration, saves the cable and connector resources, and can be functionally expanded according to different needs.

[0033] It is to be explained in the application that the application can support the equalization control of multiple battery cells at the same time and does not affect the voltage sampling signal, and the simplification based on the circuit or the design improvement for improving the circuit reliability all belong to the protection scope.

[0034] The technical principle of the application is described above in combination with specific embodiments, which are only preferred embodiments of the application. The protection scope of the application is not limited to the above-mentioned embodiments only, and any technical solution belonging to the idea of the application falls within the protection scope of the application. The other specific embodiments of the application can be thought of by the person skilled in the art without creative labor, and these embodiments will fall within the protection scope of the application.

Claims

1. A battery cell voltage sampling and equalization time-sharing control circuit, characterized by, The single sampling and equalization circuit comprises an operational amplifier U1; the time-sharing signal generating circuit comprises a multi-way selection switch U2, a decoder U3 and a microprocessor U4; the positive pole of the battery monomer B1 is connected with the positive input end of the operational amplifier U1, and the negative pole of the battery monomer B1 is connected with the negative input end of the operational amplifier U1; the operational amplifier U1 outputs the amplified signal to the multi-way selection switch U2; the microprocessor U4 outputs an analog channel selection signal to the multi-way selection switch U2 and the decoder U3 respectively; the decoder U3 judges whether to output a first time-sharing control signal to the time-sharing control circuit according to the voltage sampling requirement, thereby realizing the voltage sampling function of the battery monomer B1; the microprocessor U4 judges whether to output a second time-sharing control signal to the time-sharing control circuit according to the equalization time-sharing control requirement, thereby realizing the equalization time-sharing control function. The single sampling and equalization circuit further comprises an equalization power switch tube V1, and the time-sharing control circuit comprises an RS flip-flop U5, an NPN triode V2, a PNP triode V3 and an NPN triode V4; when the equalization condition is not met, the microprocessor U4 does not output the second time-sharing control signal, the PNP triode V3 is in the conducting state, the E and S pins of the RS flip-flop U5 are in the low level, the output end Q is in the high resistance state, the NPN triode V2 is in the off state, and the equalization power switch tube V1 is in the off state; When the equalization condition is met, the microprocessor U4 outputs the second time-sharing control signal, the PNP triode V3 is in the off state, if the voltage of the battery monomer B1 is not sampled at this time, the NPN triode V4 remains in the off state, the E and S pins of the RS flip-flop U5 are in the high level, the output end Q is in the high level, the NPN triode V2 is in the conducting state, and the equalization power switch tube V1 is in the conducting state, thereby starting the equalization control function.

2. The battery cell voltage sampling and equalization time division control circuit according to claim 1, wherein, If the voltage of the battery monomer B1 is sampled at this time, the microprocessor U4 outputs the analog channel selection signal, the decoder U3 outputs the first time-sharing control signal to the outside, which is in the high level, the NPN triode V4 changes from the off state to the conducting state, the E and S pins of the RS flip-flop U5 change from the high level to the low level, the output end Q changes from the high level to the high resistance state, the NPN triode V2 changes from the conducting state to the off state, thereby controlling the equalization power switch tube V1 to be in the off state, thereby realizing the stable sampling function of the battery monomer voltage.

3. The battery cell voltage sampling and equalization time division control circuit of claim 2, wherein, When the voltage sampling of the battery monomer B1 is completed, the first time-sharing control signal outputted by the decoder U3 to the outside disappears, the NPN triode V4 changes from the conducting state to the off state, the E and S pins of the RS flip-flop U5 change from the low level to the high level, the output pin Q changes from the high resistance to the high level, the NPN triode V2 changes from the off state to the conducting state, and the equalization power switch tube V1 is re-conducted, thereby continuing the equalization control function.

4. The battery cell voltage sampling and equalization time division control circuit of claim 3, wherein, The positive pole of the battery monomer B1 is inputted to the positive input end of the operational amplifier U1 after being divided by R3 and R5, and the negative pole of the battery monomer B1 is inputted to the negative input end of the operational amplifier U1 after being divided by R6 and R4.

5. The battery cell voltage sampling and equalization time division control circuit of claim 4, wherein, The analog channel selection signals outputted by the microprocessor U4 are TMCH0, TMCH1, TMCH2 and TMCH3.

6. The battery cell voltage sampling and equalization time division control circuit of claim 5, wherein, The first time-sharing control signal outputted by the decoder U3 is the equalization mask signal, and the second time-sharing control signal outputted by the microprocessor U4 is the equalization signal.

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