CN203287426U - An overcurrent determining circuit - Google Patents
An overcurrent determining circuit Download PDFInfo
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- CN203287426U CN203287426U CN2013203376258U CN201320337625U CN203287426U CN 203287426 U CN203287426 U CN 203287426U CN 2013203376258 U CN2013203376258 U CN 2013203376258U CN 201320337625 U CN201320337625 U CN 201320337625U CN 203287426 U CN203287426 U CN 203287426U
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Abstract
The utility model discloses an overcurrent determining circuit comprising a first filtering circuit, a second filtering circuit, a forward current overcurrent protection value reference voltage conditioning circuit, a reverse current overcurrent protection value reference voltage conditioning circuit, and a comparator. The first filtering circuit is connected with the signal output end of a current sensor 1. The second filtering circuit is connected with the signal output end of a current sensor 2. The output end of the first filtering circuit, the output end of the second filtering circuit, the output end of the forward current overcurrent protection value reference voltage conditioning circuit, and the output end of the reverse current overcurrent protection value reference voltage conditioning circuit are all connected with the input end of the comparator. The output end of the comparator is the output end of the overcurrent determining circuit. The overcurrent determining circuit has advantages of the short response time, low cost, a capability of setting an overcurrent protection value according to a requirement, and good universality.
Description
Technical field
The utility model relates to circuit field, relates in particular to a kind of overcurrent decision circuitry.
Background technology
New-energy automobile is MOSFET or IGBT constant power device with the core devices of electric machine controller, and its development trend is large electric current, high-power.The modal damage type of power device is that overcurrent damages, and therefore the output current of electric machine controller is measured accurately and is carried out reliable overcurrent protection for guaranteeing that the electric machine controller trouble free service is particularly important on the basis of Measurement accuracy.
Rely at present high-precision current sensor can measure accurately the electric current of controller, but present overcurrent protection form commonly used is for relying on software detection to carry out overcurrent protection or relying on the supersaturation detection of integrated drive chips to carry out simple overcurrent protection.
The reaction velocity of carrying out overcurrent protection after software detection is slower; can not in time measure the generation of power device overcurrent; turn-off again output signal after detecting and also need the long period; and power device is very short from spending the time that flows to damage, so the overcurrent protection after software detection can not provide overcurrent protection for power device well.The supersaturation of integrated drive chips detects and can fast detecting turn-off fast, but can't set the overcurrent protection value, and can not provide overcurrent protection to power device well when lasting large electric current does not produce supersaturation.
The utility model content
The technical problems to be solved in the utility model just is: for the problems referred to above of prior art existence; the overcurrent decision circuitry that the utility model provides that a kind of response time is short, cost is low, can set according to demand the overcurrent protection value, versatility is good; the utility model can in time be measured the generation of power device overcurrent; make current foldback circuit that hardware overcurrent protection fast in time is provided, guarantee the electric machine controller safe and highly efficient operation.
For achieving the above object, a kind of overcurrent decision circuitry of the present utility model, comprise the first filtering circuit, the second filtering circuit, forward current overcurrent protection value reference voltage modulate circuit, inverse current overcurrent protection value reference voltage modulate circuit, comparer; Above-mentioned the first filtering circuit is connected with the signal output part of current sensor one, the second filtering circuit is connected with the signal output part of current sensor two; The output terminal of above-mentioned the first filtering circuit, the second filtering circuit, forward current overcurrent protection value reference voltage modulate circuit, inverse current overcurrent protection value reference voltage modulate circuit all is connected to the input end of comparer, and the output terminal of comparer is the output terminal of this overcurrent decision circuitry.
Further, above-mentioned forward current overcurrent protection value reference voltage modulate circuit comprises resistance R 1, resistance R 2 and capacitor C 1, and resistance R 1 is connected with power supply, resistance R 2 ground connection, and resistance R 1 is connected with resistance R 2, and capacitor C 1 is connected in parallel on resistance R 2 two ends; Above-mentioned inverse current overcurrent protection value reference voltage modulate circuit comprises resistance R 3, resistance R 4 and capacitor C 2, and resistance R 3 is connected with power supply, resistance R 4 ground connection, and resistance R 3 is connected with resistance R 4, and capacitor C 2 is connected in parallel on resistance R 4 two ends.The output of capacitor C 1 and capacitor C 2 respectively is forward and reverse overcurrent protection value reference voltage.
For strengthening the novel versatility of this use, also available while making the current sensor output current signal, as further improvement of the utility model, this overcurrent decision circuitry also comprises the first input signal converting unit and the second input signal converting unit that is converted to voltage signal for the current signal that will input: wherein, the first input signal converting unit comprises resistance R 5, resistance R 5 one end ground connection, the other end is connected with the signal output part of current sensor one; The second input signal converting unit comprises resistance R 6, resistance R 6 one end ground connection, and the other end is connected with the signal output part of current sensor two.In this programme, this overcurrent decision circuitry can be used for accessing the current sensor of current-output type, and the current signal of output is converted to voltage signal through the first input signal converting unit and the second input signal converting unit can send into comparer after filtering.
Further, above-mentioned comparer comprises operational amplifier U1A, operational amplifier U1B, operational amplifier U1C, the operational amplifier U1D that is connected in parallel, and wherein: the output terminal of above-mentioned forward current overcurrent protection value reference voltage modulate circuit is connected to the in-phase input end of operational amplifier U1B and operational amplifier U1D simultaneously; The output terminal of above-mentioned inverse current overcurrent protection value reference voltage modulate circuit is connected to the inverting input of operational amplifier U1A and operational amplifier U1C simultaneously; The output terminal of above-mentioned the first filtering circuit is connected to the in-phase input end of operational amplifier U1A and the inverting input of operational amplifier U1B simultaneously; The output terminal of above-mentioned the second filtering circuit is connected to the in-phase input end of operational amplifier U1C and the inverting input of operational amplifier U1D simultaneously.The power supply termination power of operational amplifier U1A, operational amplifier U1B, operational amplifier U1C, operational amplifier U1D, earth terminal ground connection.
Further, above-mentioned the first filtering circuit and above-mentioned the second filtering circuit are the RC filter circuit.Wherein, the first filtering circuit comprises resistance R 7 and capacitor C 3, and resistance R 7 is connected with the signal output part of current sensor one, capacitor C 3 ground connection, resistance R 7 and capacitor C 3 series connection; The second filtering circuit comprises resistance R 8 and capacitor C 4, and resistance R 8 is connected with the signal output part of current sensor two, capacitor C 4 ground connection, resistance R 8 and capacitor C 4 series connection.Capacitor C 3 and capacitor C 4 respectively are the first filtering circuit and above-mentioned the second filtered output voltage of filtering circuit.
Principle of work of the present utility model is: before circuit working, the current sensor output voltage values X that the upper current limit that calculating will be protected is corresponding, adjust precision resistance R1 and R2 and make on R2 that to get voltage be X; The current sensor output voltage values Y that the electric current negative direction upper current limit that calculating will be protected is corresponding, adjust precision resistance R3 and R4 and make on R4 that to get voltage be Y.During circuit working, if the current signal of current sensor one and current sensor two outputs is converted to voltage signal Current A, Current B(current sensor one and current sensor two direct voltage output signal Current A, Current B needn't changes through the first input signal converting unit and the second input signal converting unit), voltage signal is sent into comparer after the first filtering circuit and above-mentioned the second filtering circuit filtering; Comparer judges, during greater than X or less than Y, comparer output low level signal reports an error as Current A and Current B.
, with respect to prior art, the utlity model has following advantage and beneficial effect:
1, the utility model response time is low to moderate nanosecond, fast response time, and the generation that can in time measure the power device overcurrent, make current foldback circuit that hardware overcurrent protection fast in time is provided, and guarantees the electric machine controller safe and highly efficient operation.
But 2, free setting electric machine controller overcurrent protection current value of the present utility model, highly versatile;
3, the utility model is simple in structure, cost is low.
Description of drawings
Fig. 1 is circuit diagram of the present utility model.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the utility model is described in further detail, but embodiment of the present utility model is not limited only to this.
[embodiment 1]
As shown in Figure 1, a kind of overcurrent decision circuitry of the present embodiment, comprise the first filtering circuit, the second filtering circuit, forward current overcurrent protection value reference voltage modulate circuit, inverse current overcurrent protection value reference voltage modulate circuit, comparer; Above-mentioned the first filtering circuit is connected with the signal output part of current sensor one, the second filtering circuit is connected with the signal output part of current sensor two; The output terminal of above-mentioned the first filtering circuit, the second filtering circuit, forward current overcurrent protection value reference voltage modulate circuit, inverse current overcurrent protection value reference voltage modulate circuit all is connected to the input end of comparer, and the output terminal of comparer is the output terminal of this overcurrent decision circuitry.
Above-mentioned forward current overcurrent protection value reference voltage modulate circuit is mainly a bleeder circuit, comprise resistance R 1, resistance R 2 and capacitor C 1, after resistance R 1 and resistance R 2 series connection, resistance R 1 other end also is connected with power supply, resistance R 2 other end ground connection, capacitor C 1 is connected in parallel on resistance R 2 two ends; Above-mentioned inverse current overcurrent protection value reference voltage modulate circuit also is mainly a bleeder circuit and comprises resistance R 3, resistance R 4 and capacitor C 2; after resistance R 3 and resistance R 4 series connection; resistance R 3 other ends are connected with power supply, resistance R 4 other end ground connection, and capacitor C 2 is connected in parallel on resistance R 4 two ends.The output of capacitor C 1 and capacitor C 2 respectively is forward and reverse overcurrent protection value reference voltage.Before circuit working, the current sensor output voltage values X that the upper current limit that calculating will be protected is corresponding, adjust precision resistance R1 and R2 and make on R2 that to get voltage be X; The current sensor output voltage values Y that the electric current negative direction upper current limit that calculating will be protected is corresponding, adjust precision resistance R3 and R4 and make on R4 that to get voltage be Y.Voltage X and voltage Y are sent in comparer respectively as reference voltage.
Above-mentioned the first filtering circuit and above-mentioned the second filtering circuit are the RC filter circuit.During circuit working, current sensor one and current sensor two direct voltage output signal Current A, Current B send into comparer after the first filtering circuit and the second filtering circuit filtering.
Above-mentioned comparer comprises four operational amplifier that is connected in parallel: U1A, U1B, U1C, U1D, wherein: the output terminal (output voltage X) of forward current overcurrent protection value reference voltage modulate circuit is connected to the in-phase input end of operational amplifier U1B and operational amplifier U1D simultaneously, makes; The output terminal (output voltage X) of inverse current overcurrent protection value reference voltage modulate circuit is connected to the inverting input of operational amplifier U1A and operational amplifier U1C simultaneously; The output terminal of the first filtering circuit (output voltage Current A) is connected to the in-phase input end of operational amplifier U1A and the inverting input of operational amplifier U1B simultaneously; The output terminal of the second filtering circuit (output voltage Current B) is connected to the in-phase input end of operational amplifier U1C and the inverting input of operational amplifier U1D simultaneously.
Four operational amplifier U1A, U1B, U1C, U1D judge the signal of input respectively, and as Current A and Current B during greater than X or less than Y, operational amplifier will the output low level signal, thereby comparer output low level signal reports an error.
[embodiment 2]
On the basis of embodiment 1, the overcurrent decision circuitry of the present embodiment also comprises the first input signal converting unit and the second input signal converting unit that is converted to voltage signal for the current signal that will input, wherein: the first input signal converting unit comprises resistance R 5, resistance R 5 one end ground connection, the other end is connected with the signal output part of current sensor one; The second input signal converting unit comprises resistance R 6, resistance R 6 one end ground connection, and the other end is connected with the signal output part of current sensor two.
In the present embodiment, set up the first input signal converting unit and the second input signal converting unit, this overcurrent decision circuitry can be used for accessing the current sensor of current-output type, highly versatile.Current sensor one and current sensor two output current signals are converted to respectively voltage signal Current A, Current B through the first input signal converting unit and the second input signal converting unit can send into comparer after filtering.In concrete application, if an output voltage signal, an output current signal in current sensor one and current sensor two, also can be only set up an input signal converting unit in the current sensor of output current signal and filtering circuit, and another is not established, namely according to the actual demand setting of circuit.
In the present embodiment, above-mentioned the first filtering circuit comprises resistance R 7 and capacitor C 3, resistance R 7 and capacitor C 3 series connection, and resistance R 7 other ends are connected with the signal output part of current sensor one, capacitor C 3 other end ground connection; Above-mentioned the second filtering circuit comprises resistance R 8 and capacitor C 4, resistance R 8 and capacitor C 4 series connection, and resistance R 8 other ends are connected with the signal output part of current sensor two, capacitor C 4 other end ground connection.Capacitor C 3 and capacitor C 4 respectively are the first filtering circuit and above-mentioned the second filtered output voltage of filtering circuit.
Be only below preferred implementation of the present utility model, protection domain of the present utility model also not only is confined to above-described embodiment, and all technical schemes that belongs under the utility model thinking all belong to protection domain of the present utility model.Should be pointed out that for those skilled in the art, the some improvements and modifications not breaking away under the utility model principle prerequisite, should be considered as protection domain of the present utility model.
Claims (6)
1. an overcurrent decision circuitry, is characterized in that, comprises the first filtering circuit, the second filtering circuit, forward current overcurrent protection value reference voltage modulate circuit, inverse current overcurrent protection value reference voltage modulate circuit, comparer; Described the first filtering circuit is connected with the signal output part of current sensor one, the second filtering circuit is connected with the signal output part of current sensor two; The output terminal of described the first filtering circuit, the second filtering circuit, forward current overcurrent protection value reference voltage modulate circuit, inverse current overcurrent protection value reference voltage modulate circuit all is connected to the input end of comparer, and the output terminal of comparer is the output terminal of this overcurrent decision circuitry.
2. a kind of overcurrent decision circuitry according to claim 1, it is characterized in that, described forward current overcurrent protection value reference voltage modulate circuit comprises resistance R 1, resistance R 2 and capacitor C 1, resistance R 1 is connected with power supply, resistance R 2 ground connection, resistance R 1 is connected with resistance R 2, and capacitor C 1 is connected in parallel on resistance R 2 two ends; Described inverse current overcurrent protection value reference voltage modulate circuit comprises resistance R 3, resistance R 4 and capacitor C 2, and resistance R 3 is connected with power supply, resistance R 4 ground connection, and resistance R 3 is connected with resistance R 4, and capacitor C 2 is connected in parallel on resistance R 4 two ends.
3. a kind of overcurrent decision circuitry according to claim 1 and 2, it is characterized in that, also comprise the first input signal converting unit and the second input signal converting unit that are converted to voltage signal for the current signal that will input, described the first input signal converting unit comprises resistance R 5, resistance R 5 one end ground connection, the other end is connected with the signal output part of current sensor one; Described the second input signal converting unit comprises resistance R 6, resistance R 6 one end ground connection, and the other end is connected with the signal output part of current sensor two.
4. a kind of overcurrent decision circuitry according to claim 1 and 2, is characterized in that, described comparer comprises operational amplifier U1A, operational amplifier U1B, operational amplifier U1C, the operational amplifier U1D that is connected in parallel, wherein:
The output terminal of described forward current overcurrent protection value reference voltage modulate circuit is connected to the in-phase input end of operational amplifier U1B and operational amplifier U1D simultaneously;
The output terminal of described inverse current overcurrent protection value reference voltage modulate circuit is connected to the inverting input of operational amplifier U1A and operational amplifier U1C simultaneously;
The output terminal of described the first filtering circuit is connected to the in-phase input end of operational amplifier U1A and the inverting input of operational amplifier U1B simultaneously;
The output terminal of described the second filtering circuit is connected to the in-phase input end of operational amplifier U1C and the inverting input of operational amplifier U1D simultaneously.
5. a kind of overcurrent decision circuitry according to claim 1 and 2, is characterized in that, described the first filtering circuit and described the second filtering circuit are the RC filter circuit.
6. a kind of overcurrent decision circuitry according to claim 5, is characterized in that, described the first filtering circuit comprises resistance R 7 and capacitor C 3, and resistance R 7 is connected with the signal output part of current sensor one, capacitor C 3 ground connection, resistance R 7 and capacitor C 3 series connection; Described the second filtering circuit comprises resistance R 8 and capacitor C 4, and resistance R 8 is connected with the signal output part of current sensor two, capacitor C 4 ground connection, resistance R 8 and capacitor C 4 series connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013203376258U CN203287426U (en) | 2013-06-13 | 2013-06-13 | An overcurrent determining circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013203376258U CN203287426U (en) | 2013-06-13 | 2013-06-13 | An overcurrent determining circuit |
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|---|---|
| CN203287426U true CN203287426U (en) | 2013-11-13 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2013203376258U Expired - Fee Related CN203287426U (en) | 2013-06-13 | 2013-06-13 | An overcurrent determining circuit |
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| CN (1) | CN203287426U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103323657A (en) * | 2013-06-13 | 2013-09-25 | 成都联腾动力控制技术有限公司 | Motor controller overcurrent judgment circuit |
| CN110361587A (en) * | 2019-08-07 | 2019-10-22 | 珠海格力电器股份有限公司 | A kind of over-current detection circuit with temperature-compensating |
-
2013
- 2013-06-13 CN CN2013203376258U patent/CN203287426U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103323657A (en) * | 2013-06-13 | 2013-09-25 | 成都联腾动力控制技术有限公司 | Motor controller overcurrent judgment circuit |
| CN103323657B (en) * | 2013-06-13 | 2015-09-09 | 成都联腾动力控制技术有限公司 | A kind of motor controller overcurrent judgment circuit |
| CN110361587A (en) * | 2019-08-07 | 2019-10-22 | 珠海格力电器股份有限公司 | A kind of over-current detection circuit with temperature-compensating |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20131113 Termination date: 20150613 |
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| EXPY | Termination of patent right or utility model |