Charging pile CP signal positive and negative half-wave detection circuit

Abstract

The utility model discloses a charging pile CP signal positive and negative half-wave detection circuit, which comprises a positive signal detection circuit and a negative signal detection circuit, the input end of a negative signal voltage division circuit is connected with the output end of a CP control guide signal, and the output end of the negative signal voltage division circuit is connected with the input end of a negative signal proportional amplification circuit. The output end of the cathode signal proportional amplification circuit is connected with the input end of the cathode signal low-pass filter circuit, and the output end of the cathode signal low-pass filter circuit is connected with the post-stage MCU microprocessor. According to the utility model, the CP negative half-wave control guide signal is converted into the positive phase half-wave signal through the negative electrode signal detection circuit, so that the CP negative half-wave signal can be effectively detected by the AC charging pile, the effective detection and fault sudden stop control of the negative half-wave signal can be realized, and the completeness of CP signal detection can be realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of AC charging piles, and in particular relates to a positive and negative half-wave detection circuit for a charging pile CP signal. Background Art

[0002] With the rapid development trend of new energy vehicles, the market demand for AC charging piles has also increased rapidly. As an important supporting facility for new energy vehicles, the reliability of the product design of charging piles has attracted much attention from consumers.

[0003] The CP signal is an important communication protocol for information exchange between the AC charging pile and the on-board charger OBC. The stability of its communication determines the reliability of charging. The charging pile CP signal is a positive or negative 12V level signal or pulse signal.

[0004] Currently, most AC charging piles on the market only detect the positive half-wave of the CP signal, but ignore the detection of the negative half-wave signal. Under certain conditions, the integrity of the CP signal detection cannot be met, which reduces the reliability of communication. Utility Model Content

[0005] The purpose of the utility model is to provide a charging pile CP signal positive and negative half-wave detection circuit to solve the problems raised in the above background technology. The utility model provides a charging pile CP signal positive and negative half-wave detection circuit, which has the characteristics of realizing effective detection of negative half-wave signals and fault emergency stop control, and realizing the integrity of CP signal detection.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a charging pile CP signal positive and negative half-wave detection circuit, including a positive signal detection circuit and a negative signal detection circuit, wherein the positive signal detection circuit includes a positive signal voltage divider circuit, a positive signal emitter-follower circuit and a positive signal low-pass filter circuit, the input end of the positive signal voltage divider circuit is connected to the CP control guide signal output end, the output end of the positive signal voltage divider circuit is connected to the input end of the positive signal emitter-follower circuit, and the output end of the positive signal emitter-follower circuit is connected to the input end of the positive signal low-pass filter circuit. The output end of the positive signal low-pass filter circuit is connected to the post-stage MCU microprocessor, the negative signal detection circuit includes a negative signal voltage divider circuit, a negative signal proportional amplifier circuit and a negative signal low-pass filter circuit, the input end of the negative signal voltage divider circuit is connected to the CP control guide signal output end, the output end of the negative signal voltage divider circuit is connected to the input end of the negative signal proportional amplifier circuit, the output end of the negative signal proportional amplifier circuit is connected to the input end of the negative signal low-pass filter circuit, and the output end of the negative signal low-pass filter circuit is connected to the post-stage MCU microprocessor.

[0007] In order to divide the positive voltage signal of CP to obtain a voltage signal of up to 3V, further, the positive signal voltage divider circuit includes a resistor R2 and a resistor R3, wherein one end of the resistor R2 is connected to the negative end of the diode D1, the positive end of the diode D1 is connected to the CP control guide signal output end, the other end of the resistor R2 is respectively connected to one end of the resistor R3 and the input end of the positive signal emitter-follower circuit, and the other end of the resistor R3 is connected to the ground end.

[0008] Furthermore, the positive signal emitter-follower circuit includes an operational amplifier U1A, pin 3 of the operational amplifier U1A is connected to resistors R2 and R3, pin 8 of the operational amplifier U1A is connected to +5V, pin 4 of the operational amplifier U1A is connected to -5V, and pins 2 and 1 of the operational amplifier U1A are respectively connected to the positive signal low-pass filter circuit.

[0009] In order to convert the positive voltage signal of CP into a pulsating DC wave signal, further, the positive signal low-pass filter circuit includes a resistor R1 and a capacitor C1, wherein one end of the resistor R1 is connected to pins 2 and 1 of the operational amplifier U1A, the other end of the resistor R1 is respectively connected to the ADC pin of the subsequent MCU microprocessor and one end of the capacitor C1, and the other end of the capacitor C1 is connected to the ground terminal.

[0010] In order to divide the CP negative half-wave voltage signal to obtain a voltage signal of up to -3V, further, the negative signal voltage divider circuit includes a resistor R4 and a resistor R5, wherein one end of the resistor R4 is connected to the positive end of the diode D2, the negative end of the diode D2 is connected to the CP control guide signal output end, the other end of the resistor R4 is connected to one end of the resistor R5, and the other end of the resistor R5 is connected to the negative signal proportional amplifier circuit.

[0011] In order to convert the input negative half-wave voltage division signal into a positive half-wave signal, further, the negative signal proportional amplification circuit includes an operational amplifier U1B and a resistor R6, wherein pin 6 of the operational amplifier U1B is respectively connected to the resistor R5 and one end of the resistor R6, the other end of the resistor R6 and pin 7 of the operational amplifier U1B are respectively connected to the negative signal low-pass filter circuit, and pin 5 of the operational amplifier U1B is connected to the ground terminal.

[0012] In order to convert the positive phase half-wave signal into a pulsating DC wave signal, further, the negative signal low-pass filter circuit includes a resistor R7 and a capacitor C4, wherein one end of the resistor R7 is connected to the resistor R6 and pin 7 of the operational amplifier U1B, the other end of the resistor R7 is respectively connected to the ADC pin of the subsequent MCU microprocessor and one end of the capacitor C4, and the other end of the capacitor C4 is connected to the ground terminal.

[0013] In order to perform filtering, the negative signal detection circuit further includes a capacitor C2 and a capacitor C3, wherein one end of the capacitor C2 is connected between the positive terminal of the diode D2 and the resistor R4, one end of the capacitor C3 is connected between the resistor R4 and the resistor R5, and the other ends of the capacitor C2 and the capacitor C3 are both connected to the ground terminal.

[0014] In the present utility model, the implementation method of the positive and negative half-wave detection circuit of the charging pile CP signal comprises the following steps:

[0015] (i) After the CP positive half-wave control pilot signal passes through the diode D1, it is divided by the resistors R2 and R3 to obtain a voltage signal of up to 3V. The divided voltage signal is output to the positive input terminal of the 3-pin of the operational amplifier U1A, and is output to the low-pass filter circuit composed of the resistor R1 and the capacitor C1 through the 1-pin of the operational amplifier U1A, and converted into a pulsating DC wave signal ADC1 and given to the ADC pin of the subsequent MCU microprocessor. The MCU microprocessor makes a state judgment based on the ADC sampling value;

[0016] (ii) After the CP negative half-wave control pilot signal passes through the diode D2, it is divided by the resistors R4 and R5 to divide the CP negative half-wave voltage signal to obtain a voltage signal of up to -3V. The divided voltage signal is output to the 6-pin reverse input terminal of the operational amplifier U1B. The inverting proportional amplifier composed of the operational amplifier U1B and the resistor R6 amplifies the output at a 1-fold ratio, converts the input negative half-wave divided voltage signal into a positive half-wave signal, and outputs it to the low-pass filter circuit composed of the resistor R7 and the capacitor C4, converts it into a pulsating DC wave signal ADC2 and gives it to the ADC pin of the subsequent MCU microprocessor. The MCU microprocessor makes a status judgment based on the ADC sampling value.

[0017] Furthermore, in step (a), the state judgment logic is: when the sampling voltage is 3V, it is judged to be a charging idle state; when the sampling voltage is 1.5-2.3V, it is judged to be a plugged-in state; when the sampling voltage is 0.75-1.2V, it is judged to be a charging state; in step (b), the state judgment logic is: when the pulsating DC wave signal ADC2 is detected to be 0V, it is judged to be a charging boot fault.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] The utility model converts the CP negative half-wave control guide signal into a positive phase half-wave signal through a negative pole signal detection circuit for detection by a subsequent MCU microprocessor, thereby realizing effective detection of the CP negative half-wave signal by an AC charging pile, thereby realizing effective detection of the negative half-wave signal and fault emergency stop control, realizing the integrity of CP signal detection, and improving the reliability of charging control of the AC charging pile, and having the characteristics of simple structure, high reliability and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A circuit diagram of the utility model; DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] Example 1

[0023] See also Figure 1 The utility model provides the following technical solutions: a charging pile CP signal positive and negative half-wave detection circuit, including a positive signal detection circuit and a negative signal detection circuit, wherein the positive signal detection circuit includes a positive signal voltage divider circuit, a positive signal emitter follower circuit and a positive signal low-pass filter circuit, the input end of the positive signal voltage divider circuit is connected to the output end of the CP control guide signal, the CP control guide signal is provided and output by the charging pile, the output end of the positive signal voltage divider circuit is connected to the input end of the positive signal emitter follower circuit, the output end of the positive signal emitter follower circuit is connected to the input end of the positive signal low-pass filter circuit, and the positive signal The output end of the negative signal low-pass filter circuit is connected to the post-stage MCU microprocessor, the negative signal detection circuit includes a negative signal voltage divider circuit, a negative signal proportional amplifier circuit and a negative signal low-pass filter circuit, the input end of the negative signal voltage divider circuit is connected to the CP control guide signal output end, the output end of the negative signal voltage divider circuit is connected to the input end of the negative signal proportional amplifier circuit, the output end of the negative signal proportional amplifier circuit is connected to the input end of the negative signal low-pass filter circuit, and the output end of the negative signal low-pass filter circuit is connected to the post-stage MCU microprocessor; the circuit of the utility model is integrated on the control mainboard of the charging pile.

[0024] By adopting the above technical scheme, the utility model converts the CP negative half-wave control guide signal into a positive phase half-wave signal through a negative pole signal detection circuit for detection by a subsequent MCU microprocessor, thereby realizing effective detection of the CP negative half-wave signal by the AC charging pile, thereby realizing effective detection of the negative half-wave signal and fault emergency stop control, realizing the integrity of the CP signal detection, and improving the reliability of the charging control of the AC charging pile, and having the characteristics of simple structure, high reliability and low cost.

[0025] Specifically, the positive signal voltage divider circuit includes a resistor R2 and a resistor R3, wherein one end of the resistor R2 is connected to the negative end of the diode D1, the positive end of the diode D1 is connected to the CP control guide signal output end, the other end of the resistor R2 is respectively connected to one end of the resistor R3 and the input end of the positive signal emitter-follower circuit, the other end of the resistor R3 is connected to the ground end, the diode D1 is a forward signal unidirectional conducting diode, model SS14; the resistance value of the resistor R2 is 100K, and the resistance value of the resistor R3 is 33K.

[0026] By adopting the above technical solution, the positive voltage signal of CP is divided to obtain a voltage signal of up to 3V.

[0027] Specifically, the positive signal emitter-follower circuit includes an operational amplifier U1A, pin 3 of the operational amplifier U1A is connected to resistors R2 and R3, pin 8 of the operational amplifier U1A is connected to +5V, pin 4 of the operational amplifier U1A is connected to -5V, and pins 2 and 1 of the operational amplifier U1A are respectively connected to the positive signal low-pass filter circuit; the model of the operational amplifier U1A is LM258.

[0028] Specifically, the positive signal low-pass filter circuit includes a resistor R1 and a capacitor C1, wherein one end of the resistor R1 is connected to pins 2 and 1 of the operational amplifier U1A, the other end of the resistor R1 is respectively connected to the ADC pin of the subsequent MCU microprocessor and one end of the capacitor C1, the other end of the capacitor C1 is connected to the ground terminal, the resistance value of the resistor R1 is 1K, and the capacitance value of the capacitor C1 is 100nF.

[0029] By adopting the above technical solution, the positive voltage signal of CP is converted into a pulsating DC wave signal.

[0030] Example 2

[0031] The present embodiment is different from the embodiment 1 in that: specifically, the negative signal voltage divider circuit includes a resistor R4 and a resistor R5, wherein one end of the resistor R4 is connected to the positive end of the diode D2, the negative end of the diode D2 is connected to the CP control guide signal output end, the other end of the resistor R4 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to the negative signal proportional amplifier circuit, the diode D2 is an inverting signal unidirectional conduction diode, model SS14, the resistance of the resistor R4 is 100K, and the resistance of the resistor R5 is 33K.

[0032] By adopting the above technical solution, the CP negative half-wave voltage signal is divided to obtain a voltage signal of up to -3V.

[0033] Specifically, the negative signal proportional amplification circuit includes an operational amplifier U1B and a resistor R6, wherein the 6th pin of the operational amplifier U1B is respectively connected to the resistor R5 and one end of the resistor R6, the other end of the resistor R6 and the 7th pin of the operational amplifier U1B are respectively connected to the negative signal low-pass filter circuit, the 5th pin of the operational amplifier U1B is connected to the ground terminal, the model of the operational amplifier U1B is LM258, and the resistance value of the resistor R6 is 33K.

[0034] By adopting the above technical solution, the input negative half-wave voltage division signal is converted into a positive phase half-wave signal.

[0035] Specifically, the negative signal low-pass filter circuit includes a resistor R7 and a capacitor C4, wherein one end of the resistor R7 is connected to the resistor R6 and the 7th pin of the operational amplifier U1B, the other end of the resistor R7 is respectively connected to the ADC pin of the subsequent MCU microprocessor and one end of the capacitor C4, the other end of the capacitor C4 is connected to the ground terminal, the resistance value of the resistor R7 is 1K, and the capacitance value of the capacitor C4 is 100nF.

[0036] By adopting the above technical solution, the positive phase half-wave signal is converted into a pulsating DC wave signal.

[0037] Example 3

[0038] The difference between this embodiment and Embodiment 1 is that: specifically, the negative electrode signal detection circuit also includes a capacitor C2 and a capacitor C3, wherein one end of the capacitor C2 is connected between the positive terminal of the diode D2 and the resistor R4, one end of the capacitor C3 is connected between the resistor R4 and the resistor R5, and the other ends of the capacitor C2 and the capacitor C3 are both connected to the ground terminal, and the capacitance of the capacitor C2 and the capacitor C3 are both 100nF.

[0039] By adopting the above technical solution, filtering is performed as a filter capacitor.

[0040] Example 4

[0041] Furthermore, the implementation method of the positive and negative half-wave detection circuit of the charging pile CP signal described in the utility model comprises the following steps:

[0042] (i) After the CP positive half-wave control pilot signal passes through the diode D1, it is divided by the resistors R2 and R3 to obtain a voltage signal of up to 3V. The divided voltage signal is output to the positive input terminal of the 3-pin of the operational amplifier U1A, and is output to the low-pass filter circuit composed of the resistor R1 and the capacitor C1 through the 1-pin of the operational amplifier U1A, and converted into a pulsating DC wave signal ADC1 and given to the ADC pin of the subsequent MCU microprocessor. The MCU microprocessor makes a state judgment based on the ADC sampling value;

[0043] (ii) After the CP negative half-wave control pilot signal passes through the diode D2, it is divided by the resistors R4 and R5 to divide the CP negative half-wave voltage signal to obtain a voltage signal of up to -3V. The divided voltage signal is output to the 6-pin reverse input terminal of the operational amplifier U1B. The inverting proportional amplifier composed of the operational amplifier U1B and the resistor R6 amplifies the output at a 1-fold ratio, converts the input negative half-wave divided voltage signal into a positive half-wave signal, and outputs it to the low-pass filter circuit composed of the resistor R7 and the capacitor C4, converts it into a pulsating DC wave signal ADC2 and gives it to the ADC pin of the subsequent MCU microprocessor. The MCU microprocessor makes a status judgment based on the ADC sampling value.

[0044] In step (a), the state judgment logic is: when the sampling voltage is 3V, it is judged to be a charging idle state; when the sampling voltage is 1.5-2.3V, it is judged to be a plugged-in state; when the sampling voltage is 0.75-1.2V, it is judged to be a charging state; in step (b), the state judgment logic is: when the pulsating DC wave signal ADC2 is detected to be 0V, it is judged to be a charging boot fault.

[0045] To sum up, the utility model converts the CP negative half-wave control guide signal into a positive phase half-wave signal through a negative pole signal detection circuit for detection by a subsequent MCU microprocessor, thereby realizing effective detection of the CP negative half-wave signal by the AC charging pile, thereby realizing effective detection of the negative half-wave signal and fault emergency stop control, realizing the integrity of the CP signal detection, and improving the reliability of the charging control of the AC charging pile, and having the characteristics of simple structure, high reliability and low cost.

[0046] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A charging pile CP signal positive and negative half-wave detection circuit, characterized in that: It includes a positive signal detection circuit and a negative signal detection circuit, wherein the positive signal detection circuit includes a positive signal voltage divider circuit, a positive signal emitter-follower circuit and a positive signal low-pass filter circuit, the input end of the positive signal voltage divider circuit is connected to the output end of the CP control guide signal, the output end of the positive signal voltage divider circuit is connected to the input end of the positive signal emitter-follower circuit, the output end of the positive signal emitter-follower circuit is connected to the input end of the positive signal low-pass filter circuit, and the output end of the positive signal low-pass filter circuit is connected to the post-stage MCU microprocessor; the negative signal detection circuit includes a negative signal voltage divider circuit, a negative signal proportional amplifier circuit and a negative signal low-pass filter circuit, the input end of the negative signal voltage divider circuit is connected to the output end of the CP control guide signal, the output end of the negative signal voltage divider circuit is connected to the input end of the negative signal proportional amplifier circuit, the output end of the negative signal proportional amplifier circuit is connected to the input end of the negative signal low-pass filter circuit, and the output end of the negative signal low-pass filter circuit is connected to the post-stage MCU microprocessor.

2. A charging pile CP signal positive and negative half-wave detection circuit according to claim 1, characterized in that: The positive signal voltage divider circuit includes a resistor R2 and a resistor R3, wherein one end of the resistor R2 is connected to the negative end of the diode D1, the positive end of the diode D1 is connected to the CP control guide signal output end, the other end of the resistor R2 is respectively connected to one end of the resistor R3 and the input end of the positive signal emitter-follower circuit, and the other end of the resistor R3 is connected to the ground end.

3. A charging pile CP signal positive and negative half-wave detection circuit according to claim 2, characterized in that: The positive signal emitter-follower circuit includes an operational amplifier U1A, pin 3 of the operational amplifier U1A is connected to resistors R2 and R3, pin 8 of the operational amplifier U1A is connected to +5V, pin 4 of the operational amplifier U1A is connected to -5V, and pins 2 and 1 of the operational amplifier U1A are respectively connected to the positive signal low-pass filter circuit.

4. A charging pile CP signal positive and negative half-wave detection circuit according to claim 3, characterized in that: The positive signal low-pass filter circuit includes a resistor R1 and a capacitor C1, wherein one end of the resistor R1 is connected to pins 2 and 1 of the operational amplifier U1A, the other end of the resistor R1 is respectively connected to the ADC pin of the subsequent MCU microprocessor and one end of the capacitor C1, and the other end of the capacitor C1 is connected to the ground terminal.

5. A charging pile CP signal positive and negative half-wave detection circuit according to claim 1, characterized in that: The negative signal voltage divider circuit includes a resistor R4 and a resistor R5, wherein one end of the resistor R4 is connected to the positive end of the diode D2, the negative end of the diode D2 is connected to the CP control guide signal output end, the other end of the resistor R4 is connected to one end of the resistor R5, and the other end of the resistor R5 is connected to the negative signal proportional amplifier circuit.

6. A charging pile CP signal positive and negative half-wave detection circuit according to claim 5, characterized in that: The negative signal proportional amplification circuit includes an operational amplifier U1B and a resistor R6, wherein pin 6 of the operational amplifier U1B is respectively connected to the resistor R5 and one end of the resistor R6, the other end of the resistor R6 and pin 7 of the operational amplifier U1B are respectively connected to the negative signal low-pass filter circuit, and pin 5 of the operational amplifier U1B is connected to the ground terminal.

7. A charging pile CP signal positive and negative half-wave detection circuit according to claim 6, characterized in that: The negative signal low-pass filter circuit includes a resistor R7 and a capacitor C4, wherein one end of the resistor R7 is connected to the resistor R6 and the pin 7 of the operational amplifier U1B, the other end of the resistor R7 is respectively connected to the ADC pin of the subsequent MCU microprocessor and one end of the capacitor C4, and the other end of the capacitor C4 is connected to the ground terminal.

8. A charging pile CP signal positive and negative half-wave detection circuit according to claim 6, characterized in that: The negative electrode signal detection circuit also includes a capacitor C2 and a capacitor C3, wherein one end of the capacitor C2 is connected between the positive terminal of the diode D2 and the resistor R4, one end of the capacitor C3 is connected between the resistor R4 and the resistor R5, and the other ends of the capacitor C2 and the capacitor C3 are both connected to the ground terminal.

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