Independent long-time analog timing switch control circuit

Abstract

The utility model relates to an independent long-time simulation timing switch control circuit, which comprises an isolation power supply module, an integrator module, a charging capacitor adjusting module and a relay control module. A pin 3 of the isolation power supply module outputs VEE and is connected to the integrator module. In the integrator module, the anti-phase end of an operational amplifier is connected with the VEE through a sixth resistor, the non-inverting end of the operational amplifier is connected with the VEE through a third resistor and is grounded through a fourth resistor, and the output end and the anti-phase end of the operational amplifier are directly connected with an integrating capacitance adjusting module. The charging capacitance adjusting module is formed by connecting a first capacitance branch, a second capacitance branch, a third capacitance branch, a fourth capacitance branch and a reset switch in parallel. The relay control module comprises a first triode, a relay physical switch, a charging loop switch and a relay. Compared with the prior art, the system has the advantages of wide timing range, high stability, interference resistance and the like.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of switch control especially to a long time independent analog timing switch control circuit. BACKGROUND

[0002] In the field of power electronics, the safety and stability of high-voltage charging systems have always been the focus of research. Most existing high-voltage charging systems rely on CPU systems to control the closing and switching of the front-stage contactor, thereby achieving management of the charging process. However, this CPU-dependent control method has a significant problem: when the CPU system is subjected to external interference, it may cause the control system to lose control, thereby triggering the risk of high-voltage out-of-control, and even causing serious accidents such as high-voltage electrical fires.

[0003] In order to improve the safety of high-voltage charging systems, secondary protection independent switch control is widely used. However, traditional secondary protection independent switch control mostly uses digital timers, which are usually composed of a crystal oscillator and a counter. Although they can meet the needs of timing control to some extent, over a long period of operation, due to the frequency drift of the crystal oscillator and the error accumulation of the counter, it is difficult for digital timers to guarantee stable test time for a long time, thereby affecting the stability and reliability of high-voltage charging systems. In addition, with the continuous expansion of the application field of high-voltage charging systems, higher requirements have been put forward for the precision and range of charging time. Some special application scenarios require charging time to reach 1 to 100 seconds or even longer, while traditional digital timers often fail to meet these needs in terms of timing range and time stability. Therefore, how to completely isolate the electrical connection system from the high-voltage charging system and ensure the stability and accuracy of timing is a technical problem that needs to be solved. SUMMARY

[0004] The purpose of the utility model is to overcome the defects of the prior art and provide an independent long-time analog timing switch control circuit. The circuit uses an analog integrator for timing, is independent of the electrical system, reduces high-frequency interference, and performs accurate timing.

[0005] The purpose of the utility model can be achieved through the following technical solutions:

[0006] According to an aspect of the utility model, an independent long-time analog timing switch control circuit is provided, which includes an isolation power supply module, an integrator module, a charging capacitor adjustment module, and a relay control module.

[0007] The 3-pin output VEE of the isolation power module is connected to the integrator module; in the integrator module, the inverting terminal of the operational amplifier is connected to VEE through the sixth resistor, the non-inverting terminal of the operational amplifier is connected to VEE through the third resistor, and the output terminal of the operational amplifier is connected to the ground through the fourth resistor; the output terminal and the inverting terminal of the operational amplifier are directly connected to the charging capacitor adjustment module; the charging capacitor adjustment module is composed of the first capacitor branch, the second capacitor branch, the third capacitor branch, the fourth capacitor branch and the reset switch in parallel; the relay control module includes the first triode, the relay physical switch, the charging loop switch and the relay.

[0008] The 4-pin input direct current positive voltage 24V of the isolation power module, the 1-pin output direct current positive voltage VCC and the 3-pin output direct current negative voltage VEE.

[0009] The feedback circuit of the operational amplifier in the integrator module is a series circuit of the charging capacitor adjustment module, the second diode and the fifth resistor.

[0010] The negative electrode of the second diode is connected to the charging capacitor adjustment module.

[0011] In the charging capacitor adjustment module, the first capacitor branch is the first capacitor, the second capacitor branch is the series connection of the first button switch and the second capacitor, the third capacitor branch is the series connection of the second button switch and the third capacitor, and the fourth capacitor branch is the series connection of the third button switch and the fourth capacitor.

[0012] The capacitance values of the first capacitor, the second capacitor, the third capacitor and the fourth capacitor are equal.

[0013] The positive electrode of the third diode is connected to the positive electrode of the second diode, and the negative electrode of the third diode is grounded.

[0014] The base of the first triode in the charging capacitor adjustment module and the relay control module is connected through the first diode and the first resistor.

[0015] The collector of the first triode is connected to the relay physical switch.

[0016] The reset switch is an asynchronous auxiliary switch of the charging loop switch; when the charging loop switch is closed, the reset switch is opened; and vice versa.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] (1) improve system stability: the independent long-time analog timing switch control circuit designed by adopting the analog integration circuit has higher time stability, can guarantee accurate timing time for a long time, and thereby improves the overall stability of the high-voltage charging system.

[0019] (2) Expand the timing range: By adjusting the resistance and capacitance values in the circuit, the timing range can be easily set to meet the charging needs from 1 second to 120 seconds or even longer, providing more flexible control options for high-voltage charging systems.

[0020] (3) Enhance anti-interference ability: The analog integrator circuit is less sensitive to high-frequency interference, so the circuit can maintain stable timing performance when subjected to external high-frequency interference, and is completely independent of the electrical system, effectively avoiding the risk of control system out of control and high-voltage out of control due to interference. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 An independent long-time analog timing switch control circuit diagram is provided.

[0022] Marked in the figure: U1, isolation power module; U1A, operational amplifier; RES, reset switch; R1, first resistor; R3, third resistor; R4, fourth resistor; R6, sixth resistor; D1, first diode; D2, second diode; D3, third diode; D4, fourth diode; C1, first capacitor; C2, second capacitor; C3, third capacitor; C4, fourth capacitor; S1, first button switch; S2, second button switch; S3, third button switch; Q1, first triode; RE01, relay physical switch; S4, charging circuit switch; VS1, first voltage value; VS2, second voltage value; VS3, third voltage value; VS4, fourth voltage value. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present application.

[0024] In some existing high-voltage charging systems, the commonly used timing switch controls the closing and switching of a contactor in the front stage through a CPU system to charge, but if the entire CPU system is disturbed in the high-voltage charging system, the control system may be out of control, leading to uncontrolled high voltage and system risks, and high-voltage electric fire hazards. The present embodiment provides an independent long-time analog timing switch control circuit, which is completely isolated from the high-voltage charging system itself in terms of electrical connection system, and uses a stable analog integrator circuit. As shown in Figure 1 Fig. 1 is an independent long-time analog timing switch control circuit diagram. The circuit structure includes an isolation power module, an integrator module, a charging capacitor adjustment module, and a relay control module.

[0025] The 3-pin output VEE of the isolation power module U1 is connected to the integrator module; in the integrator module, the inverting terminal 2-pin of the operational amplifier U1A is connected to VEE through the sixth resistor R6, the non-inverting terminal 3-pin of the operational amplifier U1A is connected to VEE through the third resistor R3, and the output terminal 1-pin of the operational amplifier U1A is directly connected to the charging capacitor adjustment module; the charging capacitor adjustment module is composed of a first capacitor branch, a second capacitor branch, a third capacitor branch, a fourth capacitor branch, and a reset switch RES in parallel; the relay control module includes a first triode, a relay physical switch, a charging loop switch, and a relay.

[0026] The 4-pin input DC positive voltage 24V of the isolation power module U1 is connected to the 1-pin output DC positive voltage VCC and the 3-pin output DC negative voltage VEE.

[0027] The feedback circuit of the operational amplifier U1A in the integrator module is a series circuit of the charging capacitor adjustment module, the second diode D2, and the fifth resistor R5. The negative electrode of the second diode D2 is connected to the charging capacitor adjustment module.

[0028] In the charging capacitor adjustment module, the first capacitor branch is the first capacitor C1, the second capacitor branch is a series circuit of the first button switch S1 and the second capacitor C2, the third capacitor branch is a series circuit of the second button switch S2 and the third capacitor C3, and the fourth capacitor branch is a series circuit of the third button switch S3 and the fourth capacitor C4. The capacitance values of the first capacitor C1, the second capacitor C2, the third capacitor C3, and the fourth capacitor C4 are equal. The positive electrode of the third diode D3 is connected to the positive electrode of the second diode D2, and the negative electrode of the third diode D3 is grounded.

[0029] The base of the first triode Q1 in the charging capacitor adjustment module and the relay control module is connected through the first diode D1 and the first resistor R1. The collector of the first triode Q1 is connected to the relay physical switch RE01. The reset switch RES is an asynchronous auxiliary switch of the charging loop switch S4; when the charging loop switch S4 is closed, the reset switch RES is open; conversely, when the charging loop switch S4 is open, the reset switch RES is closed.

[0030] In the operation of the circuit of the embodiment, the 4-pin input DC positive voltage 24V of the isolation power module U1, the 1-pin output DC positive voltage VCC is 15V, and the 3-pin output DC negative voltage VEE is -15V. When the charging circuit switch S4 is closed and the reset switch RES is disconnected, the voltage VEE charges the charging capacitor adjustment module through the sixth resistor R6, and the integrator module starts to work. At this time, the first voltage value VS1 is VS1=R4*Vee / (R3+R4). According to the virtual break characteristic of the operational amplifier, the first voltage value VS1 is equal to the second voltage value VS2, VS2=VS1. According to the virtual short characteristic of the operational amplifier, the third voltage value VS3 is equal to the first voltage value VS1 which is equal to the second voltage value VS2, VS3=VS2=VS1=R4*Vee / (R3+R4). In the embodiment, R3=20K, R4=10K, and the third voltage value VS3=5V. After the reset switch RES is disconnected, the first capacitor C1 starts to charge, forming an integral feedback circuit, and the charging current I=VS3 / R6. Through the linear charging of the first capacitor C1, the inverting input of the operational amplifier U1A is lowered, the virtual short circuit is destroyed, and the fourth voltage VS4 of the output pin 1 of the operational amplifier U1A slowly rises. When the fourth voltage VS4 of the output pin 1 of the operational amplifier U1A reaches the conduction voltage 0.6V of the first diode D1, the first diode D1 is turned on, the conduction voltage starting point is limited by the voltage drop 0.6 to 0.7V of the diode itself, the current of the first resistor R1 is limited, and the first triode Q1 is turned on. The second diode D2 and the third diode D3 are used to isolate and raise the negative end zero point of the charging capacitor adjustment module. The relay physical switch RE01 (normally closed) control end works, and the disconnection of the relay physical switch RE01 disconnects the charging circuit, so as to achieve the purpose of disconnecting the protection switch in a fixed time. The fourth diode D4 is used to discharge the direction impact voltage of the control coil. In the case that the sixth resistor R6 has a fixed resistance, the total capacity of the charging capacitor adjustment module is adjusted through the first button switch S1, the second button switch S2 and the third button switch, so as to change the timing time. The capacities of the first capacitor C1, the second capacitor C2, the third capacitor C3 and the fourth capacitor C4 are equal. In the embodiment, the resistance of the sixth resistor R6 is fixed as 20MΩ, the capacities of the first capacitor C1, the second capacitor C2, the third capacitor C3 and the fourth capacitor C4 are 1μF, and the timing time formed is 100S. The charging time T=5*R6*C, C is the total capacity of the charging capacitor adjustment module. The power supply of the whole circuit is a DC isolation power supply, and the external control is a physical relay, so the effect of complete independence and electrical isolation is achieved.

[0031] The above merely describes a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any skilled person in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present application, and these modifications or replacements should be encompassed within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A stand-alone long-time analog timing switch control circuit, characterized in that, The circuit comprises an isolation power module, an integrator module, a charging capacitor adjustment module and a relay control module. The 3-pin output VEE of the isolation power module is connected to the integrator module; in the integrator module, the inverting terminal of the operational amplifier is connected to VEE through the sixth resistor, the non-inverting terminal of the operational amplifier is connected to VEE through the third resistor and grounded through the fourth resistor; the output terminal and the inverting terminal of the operational amplifier are directly connected to the charging capacitor adjustment module; the charging capacitor adjustment module is composed of a first capacitor branch, a second capacitor branch, a third capacitor branch, a fourth capacitor branch and a reset switch in parallel; the relay control module comprises a first triode, a relay physical switch, a charging loop switch and a relay.

2. An independent long time analog timing switch control circuit according to claim 1, characterized in that, The 4-pin input direct current positive voltage 24V of the isolation power module, the 1-pin output direct current positive voltage VCC and the 3-pin output direct current negative voltage VEE.

3. An independent long time analog timing switch control circuit according to claim 1, characterized in that, The feedback circuit of the operational amplifier in the integrator module is a series circuit of the charging capacitor adjustment module, a second diode and a fifth resistor.

4. An independent long time analog timing switch control circuit according to claim 3, characterized in that, The negative electrode of the second diode is connected to the charging capacitor adjustment module.

5. The independent long time analog timing switch control circuit according to claim 1, wherein, In the charging capacitor adjustment module, the first capacitor branch is a first capacitor, the second capacitor branch is a series circuit of a first button switch and a second capacitor, the third capacitor branch is a series circuit of a second button switch and a third capacitor, and the fourth capacitor branch is a series circuit of a third button switch and a fourth capacitor.

6. An independent long time analog timing switch control circuit according to claim 5, characterized in that, The capacitance values of the first capacitor, the second capacitor, the third capacitor and the fourth capacitor are equal.

7. An independent long time analog timing switch control circuit according to claim 1, wherein, The positive electrode of a third diode is connected to the positive electrode of the second diode, and the negative electrode of the third diode is grounded.

8. An independent long time analog timing switch control circuit according to claim 1, wherein, The base of the first triode in the charging capacitor adjustment module and the relay control module is connected to the first diode and the first resistor.

9. An independent long time analog timing switch control circuit according to claim 1, wherein, The collector of the first triode is connected to the relay physical switch.

10. The independent long time analog timing switch control circuit according to claim 1, wherein, The reset switch is an asynchronous auxiliary switch of the charging loop switch; when the charging loop switch is closed, the reset switch is opened; and vice versa.

Images