CN219245658U - High-voltage sampling circuit of electric drive system of electric automobile and electric automobile - Google Patents
High-voltage sampling circuit of electric drive system of electric automobile and electric automobile Download PDFInfo
- Publication number
- CN219245658U CN219245658U CN202223360123.5U CN202223360123U CN219245658U CN 219245658 U CN219245658 U CN 219245658U CN 202223360123 U CN202223360123 U CN 202223360123U CN 219245658 U CN219245658 U CN 219245658U
- Authority
- CN
- China
- Prior art keywords
- voltage
- circuit
- resistor
- output end
- operational amplifier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Measurement Of Current Or Voltage (AREA)
Abstract
The utility model discloses a high-voltage sampling circuit of an electric driving system of an electric automobile, which comprises a voltage dividing circuit, a voltage value converting circuit, an isolation voltage converting circuit, a voltage follower circuit and an RC filter circuit, wherein the voltage dividing circuit is formed by connecting a plurality of resistors in series, and two ends of the voltage dividing circuit are respectively connected to two ends of a high-voltage bus; the output end of the voltage dividing circuit is connected to the input end of the voltage value converting circuit, the output end of the voltage value converting circuit is connected to the input end of the isolation voltage converting circuit, the output end of the isolation voltage converting circuit is connected to the input end of the voltage following circuit, and the output end of the voltage following circuit outputs the sampled voltage through the RC filter circuit. The utility model has the advantages that: the scheme of matching the large-resistance resistor with the operational amplifier with the isolation transformer with low cost is adopted, so that lower cost is realized, electric isolation between high voltage and low voltage is realized, reliability and safety of voltage acquisition are ensured, and meanwhile, the method has the advantage of low cost.
Description
Technical Field
The utility model relates to the technical field of electric automobiles, in particular to a high-voltage sampling circuit of an electric driving system of an electric automobile and the electric automobile.
Background
In the working process of the electric driving system of the electric automobile, the motor controller needs to monitor the high-voltage bus voltage in real time for diagnosis and upload the bus voltage to the CAN network. When the bus voltage is over-voltage and exceeds the upper limit threshold of the working voltage of the electric drive system, the electric drive system needs to stop working to protect the electric drive system from being damaged. When the bus voltage is undervoltage, the electric drive system can perform power reduction work if the bus voltage does not exceed the lower limit threshold of the working voltage of the electric drive system, and stops working if the bus voltage is lower than the lower limit threshold of the working voltage of the electric drive system.
In the prior art, the high-voltage bus voltage sampling basically adopts a special chip to realize high-voltage acquisition, and the use of the special chip can increase the cost; and the insulation between high voltage and low voltage is not achieved, so that the insulation cannot meet the requirement, and a certain potential safety hazard exists.
Disclosure of Invention
The utility model aims to overcome the defects of the prior art, and provides a high-voltage sampling circuit of an electric driving system of an electric automobile and the electric automobile, wherein the scheme of matching a low-cost large-resistance resistor with an operational amplifier and an isolation transformer is adopted, so that the low cost is realized, the electrical isolation between high voltage and low voltage is realized, and the defects of high cost and no isolation of a special chip in the prior art are overcome.
In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows: the high-voltage sampling circuit of the electric drive system of the electric automobile comprises a voltage dividing circuit, a voltage value converting circuit, an isolation voltage converting circuit, a voltage following circuit and an RC filter circuit, wherein the voltage dividing circuit is formed by connecting a plurality of resistors in series, and two ends of the voltage dividing circuit are respectively connected to two ends of a high-voltage bus; the output end of the voltage dividing circuit is connected to the input end of the voltage value converting circuit, the output end of the voltage value converting circuit is connected to the input end of the isolation voltage converting circuit, the output end of the isolation voltage converting circuit is connected to the input end of the voltage following circuit, and the output end of the voltage following circuit outputs the sampled voltage through the RC filter circuit.
One of the resistors in the voltage dividing circuit is used as a sampling resistor, and output terminals are led out from two ends of the sampling resistor and connected to the voltage value conversion circuit.
The voltage value conversion circuit comprises resistors R5, R6, R7 and R8 and an operational amplifier U1, wherein the non-inverting input end of the operational amplifier U1 is connected to one end of a sampling resistor through the resistor R5, and the other end of the sampling resistor is connected to the inverting input end of the operational amplifier U1 through the resistor R7; the non-inverting input end of the operational amplifier U1 is grounded through a resistor R6; the inverting input end of the operational amplifier U1 is connected to the output end of the operational amplifier U1 through a resistor R8; the output end of the operational amplifier U1 is used as the output end of the voltage value conversion circuit.
The isolation voltage conversion circuit comprises an isolation transformer T1, an MOS tube Q1, a rectifying diode D1, a resistor R9 and a capacitor C1, wherein a first end of the primary side of the isolation transformer T1 is connected to the output end of the voltage value conversion circuit, a second end of the primary side of the isolation transformer T1 is connected to the collector electrode of the MOS tube Q1, the emitter electrode of the MOS tube Q1 is grounded, and the base electrode of the MOS tube Q1 inputs PWM signals; the secondary side first end of the transformer T1 is connected to the anode of the diode D1; the secondary side second end of the transformer T1 is grounded; the cathode of the rectifying diode D1 is grounded through a resistor R9; the two ends of the resistor R9 are connected in parallel with a capacitor C1; the cathode of the rectifying diode D1 is led out of the output end of the isolation voltage conversion circuit.
The voltage follower circuit comprises an operational amplifier U2, and the non-inverting input end of the operational amplifier U2 is connected to the output end of the isolation voltage conversion circuit; the inverting input end of the operational amplifier U2 is connected with the output end thereof; the output end leading-out terminal of the operational amplifier U2 is used as the output end of the voltage follower circuit.
The RC filter circuit comprises a resistor R10 and a capacitor C3, wherein the output end of the voltage follower circuit is connected to one end of the resistor R10, and the other end of the resistor R10 is grounded from the C3 through a point; a terminal is led out between the capacitor C3 and the resistor R10 as an output terminal for the sampled voltage.
The electric automobile adopts the electric drive system high-voltage sampling circuit to sample the electric drive system of the electric automobile at high voltage.
The utility model has the advantages that: the scheme of matching the large-resistance resistor with the operational amplifier with the isolation transformer with low cost is adopted, so that lower cost is realized, electric isolation between high voltage and low voltage is realized, reliability and safety of voltage acquisition are ensured, and meanwhile, the method has the advantage of low cost.
Drawings
The contents of the drawings and the marks in the drawings of the present specification are briefly described as follows:
fig. 1 is a schematic circuit diagram of a high voltage sampling circuit according to the present utility model.
Detailed Description
The following detailed description of the utility model refers to the accompanying drawings, which illustrate preferred embodiments of the utility model in further detail.
In the embodiment, the low-cost large-resistance resistor and the operational amplifier are matched with the isolating transformer, so that the low cost is realized, and the electrical isolation between high voltage and low voltage is realized. The voltage dividing circuit composed of a plurality of resistors is used for dividing the voltage of the high-voltage bus, the voltage after the voltage division is subjected to voltage reduction conversion through the operational amplifier, then the voltage value is converted through the isolation transformer, and the secondary voltage of the transformer is processed through the operational amplifier follower circuit and then is sent to the control circuit. The specific scheme is as follows:
as shown in fig. 1, the high-voltage sampling circuit of the electric driving system of the electric automobile comprises a voltage dividing circuit, a voltage value conversion circuit, an isolation voltage conversion circuit, a voltage follower circuit and an RC filter circuit;
the voltage dividing circuit is formed by connecting a plurality of resistors in series, and two ends of the voltage dividing circuit are respectively connected to two ends of the high-voltage bus; the output end of the voltage dividing circuit is connected to the input end of the voltage value converting circuit, the output end of the voltage value converting circuit is connected to the input end of the isolation voltage converting circuit, the output end of the isolation voltage converting circuit is connected to the input end of the voltage following circuit, and the output end of the voltage following circuit outputs the sampled voltage through the RC filter circuit.
A voltage dividing circuit:
one of the resistors in the voltage dividing circuit is used as a sampling resistor, and output terminals are led out from two ends of the sampling resistor and connected to the voltage value conversion circuit. The resistors with large resistance values are all resistors, so that the requirements of smaller working current and high-voltage insulation distance can be met. One of the resistors is used as a sampling resistor, two end leading-out terminals of the sampling resistor are used as output ends of a voltage dividing circuit, as shown in fig. 1, resistors R1-R4 are connected in series, wherein R3 is used as the sampling resistor, and two end leading-out terminals of the sampling resistor are connected to an operational amplifier U1.
A voltage value conversion circuit:
the voltage value conversion circuit comprises resistors R5, R6, R7 and R8 and an operational amplifier U1, wherein the non-inverting input end of the operational amplifier U1 is connected to one end of a sampling resistor through the resistor R5, and the other end of the sampling resistor is connected to the inverting input end of the operational amplifier U1 through the resistor R7; the non-inverting input end of the operational amplifier U1 is grounded through a resistor R6; the inverting input end of the operational amplifier U1 is connected to the output end of the operational amplifier U1 through a resistor R8; the output end of the operational amplifier U1 is used as the output end of the voltage value conversion circuit. The voltage-reducing circuit is used for reducing voltage, and the voltage obtained through voltage division is further subjected to voltage reduction.
An isolated voltage conversion circuit:
the isolation voltage conversion circuit comprises an isolation transformer T1, an MOS tube Q1, a rectifier diode D1, a resistor R9 and a capacitor C1, wherein the isolation transformer T1, the MOS tube Q1, the rectifier diode D1, a load R9 and a filter capacitor C1 form a flyback isolation voltage conversion circuit. The first end of the primary side of the isolation transformer T1 is connected to the output end of the voltage value conversion circuit, the second end of the primary side of the isolation transformer T1 is connected to the collector of the MOS tube Q1, the emitter of the MOS tube Q1 is grounded, and the base of the MOS tube Q1 inputs PWM signals; the secondary side first end of the transformer T1 is connected to the anode of the diode D1; the secondary side second end of the transformer T1 is grounded; the cathode of the rectifying diode D1 is grounded through a resistor R9; the two ends of the resistor R9 are connected in parallel with a capacitor C1; the cathode of the rectifying diode D1 is led out of the output end of the isolation voltage conversion circuit.
Voltage follower circuit:
the voltage follower circuit comprises an operational amplifier U2, and the non-inverting input end of the operational amplifier U2 is connected to the output end of the isolation voltage conversion circuit; the inverting input end of the operational amplifier U2 is connected with the output end thereof; the output end leading-out terminal of the operational amplifier U2 is used as the output end of the voltage follower circuit.
RC filter circuit:
the RC filter circuit comprises a resistor R10 and a capacitor C3, wherein the output end of the voltage follower circuit is connected to one end of the resistor R10, and the other end of the resistor R10 is grounded from the C3 through a point; a terminal is led out between the capacitor C3 and the resistor R10 as an output terminal for the sampled voltage.
The principle of the circuit in this embodiment includes:
HV+ is positive voltage of the high-voltage bus, HV-is negative voltage of the high-voltage bus, and the voltage value of the high-voltage bus is V IN 。
R1, R2, R3 and R4 form a voltage dividing circuit, and the high-voltage bus voltage is sampled. The voltage values of the two ends of R3 are the sampling voltage V SEN ＝V IN * R3/(r1+r2+r3+r4). R1, R2, R3 and R4 use large-value resistors, and the number can be more, so as to ensure smaller working current and high-voltage insulation distance requirements.
Because the high-voltage sampling voltage value output by the voltage dividing circuit is inconvenient for the signal processing circuit to directly process, V is SEN The voltage is processed by a voltage value conversion circuit formed by operational amplifier U1, resistors R5, R6, R7 and R8, and the voltage is reduced. In this circuit, r5=r7, r6=r8. The output voltage value of the operational amplifier U1 is V O1 ＝V SEN *R8/R7。
Isolation transformer T1, MOS tube Q1, rectifier diode D1, load R9 andthe filter capacitor C1 forms a flyback isolated voltage conversion circuit. The MOS transistor operates at a fixed kHz level frequency F and a fixed duty cycle D, with a ratio n=1 for T1. The secondary voltage of the transformer is rectified by a diode D1 and then V O2 ＝A*V O1 . R9 is V O2 Providing a smaller load, C1 versus output voltage V O2 Filtering is performed.
V O2 The voltage follower circuit of the operational amplifier U2 is used for carrying out impedance matching, then the voltage U_DC is output after passing through the RC filter circuit formed by the R10 and the C3, the U_DC is used as a high-voltage bus voltage sampling signal to be output to the control circuit main control chip, and the main control chip realizes real-time monitoring of the high-voltage bus voltage through internal software program conversion.
The circuit can realize high-voltage sampling by adopting simple components, has low cost, high-low voltage isolation, good insulation and high reliability, and can accurately and reliably realize the acquisition of high-voltage signals.
It is obvious that the specific implementation of the present utility model is not limited by the above-mentioned modes, and that it is within the scope of protection of the present utility model only to adopt various insubstantial modifications made by the method conception and technical scheme of the present utility model.
Claims (7)
1. The utility model provides an electric automobile electricity drives system high voltage sampling circuit which characterized in that: the high-voltage bus comprises a voltage dividing circuit, a voltage value converting circuit, an isolation voltage converting circuit, a voltage follower circuit and an RC filter circuit, wherein the voltage dividing circuit is formed by connecting a plurality of resistors in series, and two ends of the voltage dividing circuit are respectively connected to two ends of a high-voltage bus; the output end of the voltage dividing circuit is connected to the input end of the voltage value converting circuit, the output end of the voltage value converting circuit is connected to the input end of the isolation voltage converting circuit, the output end of the isolation voltage converting circuit is connected to the input end of the voltage following circuit, and the output end of the voltage following circuit outputs the sampled voltage through the RC filter circuit.
2. The high voltage sampling circuit of an electric drive system of an electric vehicle as claimed in claim 1, wherein: one of the resistors in the voltage dividing circuit is used as a sampling resistor, and output terminals are led out from two ends of the sampling resistor and connected to the voltage value conversion circuit.
3. The high voltage sampling circuit of an electric drive system of an electric vehicle as claimed in claim 2, wherein: the voltage value conversion circuit comprises resistors R5, R6, R7 and R8 and an operational amplifier U1, wherein the non-inverting input end of the operational amplifier U1 is connected to one end of a sampling resistor through the resistor R5, and the other end of the sampling resistor is connected to the inverting input end of the operational amplifier U1 through the resistor R7; the non-inverting input end of the operational amplifier U1 is grounded through a resistor R6; the inverting input end of the operational amplifier U1 is connected to the output end of the operational amplifier U1 through a resistor R8; the output end of the operational amplifier U1 is used as the output end of the voltage value conversion circuit.
4. A high voltage sampling circuit for an electric drive system of an electric vehicle as claimed in claim 2 or 3, wherein: the isolation voltage conversion circuit comprises an isolation transformer T1, an MOS tube Q1, a rectifying diode D1, a resistor R9 and a capacitor C1, wherein a first end of the primary side of the isolation transformer T1 is connected to the output end of the voltage value conversion circuit, a second end of the primary side of the isolation transformer T1 is connected to the collector electrode of the MOS tube Q1, the emitter electrode of the MOS tube Q1 is grounded, and the base electrode of the MOS tube Q1 inputs PWM signals; the secondary side first end of the transformer T1 is connected to the anode of the diode D1; the secondary side second end of the transformer T1 is grounded; the cathode of the rectifying diode D1 is grounded through a resistor R9; the two ends of the resistor R9 are connected in parallel with a capacitor C1; the cathode of the rectifying diode D1 is led out of the output end of the isolation voltage conversion circuit.
5. The high voltage sampling circuit of an electric drive system of an electric vehicle as claimed in claim 4, wherein: the voltage follower circuit comprises an operational amplifier U2, and the non-inverting input end of the operational amplifier U2 is connected to the output end of the isolation voltage conversion circuit; the inverting input end of the operational amplifier U2 is connected with the output end thereof; the output end leading-out terminal of the operational amplifier U2 is used as the output end of the voltage follower circuit.
6. The high voltage sampling circuit of an electric drive system of an electric vehicle as claimed in claim 4, wherein: the RC filter circuit comprises a resistor R10 and a capacitor C3, wherein the output end of the voltage follower circuit is connected to one end of the resistor R10, and the other end of the resistor R10 is grounded from the C3 through a point; a terminal is led out between the capacitor C3 and the resistor R10 as an output terminal for the sampled voltage.
7. An electric automobile, characterized in that: the electric automobile adopts the high-voltage sampling circuit of the electric drive system according to any one of claims 1-6 to sample the high voltage of the electric drive system of the electric automobile.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223360123.5U CN219245658U (en) | 2022-12-14 | 2022-12-14 | High-voltage sampling circuit of electric drive system of electric automobile and electric automobile |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223360123.5U CN219245658U (en) | 2022-12-14 | 2022-12-14 | High-voltage sampling circuit of electric drive system of electric automobile and electric automobile |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219245658U true CN219245658U (en) | 2023-06-23 |
Family
ID=86846945
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202223360123.5U Active CN219245658U (en) | 2022-12-14 | 2022-12-14 | High-voltage sampling circuit of electric drive system of electric automobile and electric automobile |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN219245658U (en) |
-
2022
- 2022-12-14 CN CN202223360123.5U patent/CN219245658U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106379186B (en) | Charger and automobile | |
| CN219245658U (en) | High-voltage sampling circuit of electric drive system of electric automobile and electric automobile | |
| CN202550906U (en) | DC (Direct Current) high voltage generator | |
| CN109217773B (en) | Motor control system applied to 48V vehicle-mounted power supply | |
| CN201550024U (en) | Double transistor forward high voltage DC electricity getting unit with neutral points | |
| CN1661384A (en) | Device for testing electric pulse strength for insulation | |
| CN213937521U (en) | Three-stage topological structure charger with high-low voltage output | |
| CN209963971U (en) | Vehicle-mounted dual-purpose inverter | |
| CN212784820U (en) | Storage battery power supply optimization control system for suspension type monorail vehicle | |
| CN209247857U (en) | High pressure samples diagnostic circuit | |
| CN209217954U (en) | The driving circuit and converters of converters bridge architecture | |
| CN208508801U (en) | A kind of more level resonance DC-DC converters | |
| CN1464626A (en) | High-power high-voltage D. C. electrostatic electric power unit | |
| CN110611442A (en) | PWM (pulse-width modulation) rectifying circuit for charging pile | |
| CN211629884U (en) | Charging circuit and alternating current charging equipment of electric automobile | |
| CN209399536U (en) | Circuit board and air conditioner | |
| CN2569435Y (en) | High power high voltage DC static power source device | |
| CN217427664U (en) | Protection circuit for elevator band-type brake | |
| CN207541145U (en) | Isolated busbar voltage detection circuit | |
| CN220475620U (en) | Single-phase inverter of detection vehicle | |
| CN104638921A (en) | DC-DC conversion power supply circuit for data collector | |
| CN113054647B (en) | Energy recovery device of DC/DC module | |
| CN215575297U (en) | High-frequency pulse current signal generating circuit | |
| CN217656560U (en) | Anti-disturbance direct-current isolation voltage conversion circuit | |
| CN203951381U (en) | Vehicle-mounted inversion system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |