CN101478235A - Control circuit for non-isolation type bidirectional DC/DC converter and control method thereof - Google Patents
Control circuit for non-isolation type bidirectional DC/DC converter and control method thereof Download PDFInfo
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- CN101478235A CN101478235A CNA2009100102165A CN200910010216A CN101478235A CN 101478235 A CN101478235 A CN 101478235A CN A2009100102165 A CNA2009100102165 A CN A2009100102165A CN 200910010216 A CN200910010216 A CN 200910010216A CN 101478235 A CN101478235 A CN 101478235A
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Abstract
The invention discloses a control circuit of a non-isolated bidirectional DC/DC transducer and a control method thereof. The control circuit comprises an input voltage sensor, an input current sensor, an output voltage sensor, a DSP control plate and an IGBT driver circuit. The input voltage sensor is connected in parallel to the input terminal on the main circuit of the bidirectional DC/DC transducer. The input current sensor is connected in series to the input circuit on the main circuit of the bidirectional DC/DC transducer. The output voltage sensor is connected in parallel to the output terminal on the main circuit of the bidirectional DC/DC transducer. The DSP control plate is respectively connected with the input voltage sensor, the input current sensor, the output voltage sensor and IGBT drive circuit. The control method comprises sampling, inner voltage loop regulating, inner current loop regulating and generating PWM waveform. An automatic control unit is added to the invention so as to write the major algorithm of the control method to the DSP control plate. Therefore the automatization level of the non-isolated bidirectional DC/DC transducer is improved.
Description
Technical field
The present invention relates to a kind of control circuit and control method thereof of two-way DC/DC converter, particularly relate to the control circuit and the control method thereof of a kind of non-isolation type bidirectional DC/DC converter.
Background technology
Non-isolation type bidirectional DC/DC converter is essentially a Switching Power Supply, keeps stable in order to make output voltage, and reaches certain precision of voltage regulation, generally adopts single close loop negative feedback control method.The key step of this method is: obtain driving conducting, the shutoff ratio of IGBT after the difference of voltage given value and Voltage Feedback value is regulated through PI, the PI parameter by appropriate design promptly can guarantee the converter steady operation.This method control is simple, easy to adjust, therefore is used widely in engineering.But the closed-loop control of voltage list is owing to have only a zero point in the voltage open-loop transfer function, response speed is slower, have relatively high expectations in dynamic property to converter, as setting up aspects such as charging and discharging currents fast, single closed-loop control just is difficult to satisfy the demand, and this mainly is because can not control the electric current of dynamic process fully as required in single closed-loop control.When converter is subjected to certain disturbance, as change in voltage, inductance or other element disturbances, all will be reflected to output, output voltage is changed after, Voltage loop just works, and causes control lag.Under converter startup or other transient state situation, occur problems such as overcurrent in addition easily, thereby reduced the overall performance of converter.
Summary of the invention
For overcoming the problems referred to above that prior art exists, the objective of the invention is to design a kind of control circuit of the non-isolation type bidirectional DC/DC converter with two closed-loop controls and propose the control method of one pair of closed loops.
For achieving the above object, technical scheme of the present invention is as follows: the control circuit of a kind of non-isolation type bidirectional DC/DC converter, comprise input voltage sensor, output voltage sensor, the DSP control board, the IGBT drive circuit, described input voltage sensor is parallel to the input of two-way DC/DC inverter main circuit, output voltage sensor is parallel to the output of two-way DC/DC inverter main circuit, described DSP control board respectively with the 3rd terminal of input voltage sensor, the 3rd terminal of output voltage sensor and IGBT drive circuit connect, described control circuit also comprises the input current transducer, described input current sensor string is linked to the input circuit of two-way DC/DC inverter main circuit, and the 3rd terminal of input current transducer is connected with the DSP control board.
DSP control board of the present invention is made up of digital signal processor DSP and peripheral circuit.
Peripheral circuit of the present invention comprises that crystal oscillator, power supply, AD sampling, PWM export isolation.
Digital signal processor DSP of the present invention is the TMS320LF2407 digital signal processor.
The control method of the control circuit of a kind of non-isolation type bidirectional DC/DC converter may further comprise the steps:
A, sampling: respectively input voltage, output voltage and the input current of two-way DC/DC inverter main circuit are sampled by input voltage sensor, output voltage sensor, input current transducer;
B, outer voltage are regulated: whether the input voltage sampled value of being judged two-way DC/DC inverter main circuit by the control program of DSP control board reaches limit value, if do not reach limit value, then call the constant voltage program that discharges and recharges and produce the reference current that electric current loop is regulated, if reach limit value, then call the constant current charge-discharge program and produce the reference current that electric current loop is regulated;
C, current inner loop are regulated: the control program by the DSP control board compares the reference current of electric current loop and the sample rate current value of input current transducer, and produces the duty ratio that drives IGBT conducting, shutoff;
D, produce the PWM waveform: produce the PWM waveform by the control program of DSP control board according to the duty ratio of IGBT conducting, shutoff, drive the IGBT of two-way DC/DC inverter main circuit by the IGBT drive circuit.
What outer voltage of the present invention was regulated, current inner loop is regulated employing is the anti-saturated digital pi regulator of integration.
The method of sampling of the present invention is continuous sampling 10 times, by the DSP control board sampled signal is carried out digital filtering, and the method for filtering is that 10 sampled signals are removed maximum and minimum value, asks arithmetic mean with remaining 8 sampled value again.
Control program of the present invention is the core algorithm program of control method, writes the DSP control board in advance.
Compared with prior art, the present invention has following beneficial effect:
1, since the present invention with the main circuit of non-isolation type bidirectional DC/DC converter and feedback control circuit as an automatic control system, and adding automatic control unit, the core algorithm of control method is write the DSP control board, improved the automatization level of non-isolation type bidirectional DC/DC converter.
2, because the pi regulator that the present invention adopts proportional integral as means for correcting, has improved the stability of system, taken into account the requirement of quick response and elimination static difference two aspects, adopt digital PI control method in the program, can prevent that integration is saturated.
3, because the present invention has adopted the state space method of average that non-isolation type bidirectional DC/DC converter has been carried out mathematical modeling, the PI parameter of calculating voltage, Current Regulation theoretically, using for engineering provides theoretical direction.
4, because the stability of a system that control algolithm of the present invention can make non-isolation type bidirectional DC/DC form is strong, stability range is wide, have good dynamic response, can be in DC bus-bar voltage excursions such as flywheel energy storage, fuel cell system, wind power generations big and need carry out the middle low power application scenario that DC converting handles and apply.
Description of drawings
2 in the total accompanying drawing of the present invention, wherein:
Fig. 1 is the control circuit figure of two-way DC/DC converter.
Fig. 2 is the flow chart of two-way DC/DC convertor controls method.
Among the figure, 1, the DSP control board, 2, input voltage sensor, 3, the IGBT drive circuit, 4, the input current transducer, 5, output voltage sensor, 6, two-way DC/DC inverter main circuit.
Embodiment
Below in conjunction with accompanying drawing the present invention is further specified.As shown in Figure 1, the control circuit of a kind of non-isolation type bidirectional DC/DC converter, comprise input voltage sensor 2, input current transducer 4, output voltage sensor 5, DSP control board 1, IGBT drive circuit 3, described input voltage sensor 2 is parallel to the input of two-way DC/DC inverter main circuit 6, input current transducer 4 is connected in series to the input circuit of two-way DC/DC inverter main circuit 6, output voltage sensor 5 is parallel to the output of two-way DC/DC inverter main circuit 6, described DSP control board 1 respectively with the 3rd terminal of input voltage sensor 2, the 3rd terminal of input current transducer 4, the 3rd terminal of output voltage sensor 5 and IGBT drive circuit 3 connect.Described DSP control board 1 is by digital signal processor DSP and comprise that peripheral circuits such as crystal oscillator, power supply, AD sampling, PWM output isolation form.Described digital signal processor DSP is the TMS320LF2407 digital signal processor.
As shown in Figure 2, the control method of the control circuit of a kind of non-isolation type bidirectional DC/DC converter may further comprise the steps:
A, sampling: respectively input voltage, output voltage and the input current of two-way DC/DC inverter main circuit 6 are sampled by input voltage sensor 2, output voltage sensor 5, input current transducer 4, the described method of sampling is continuous sampling 10 times, carry out digital filtering by 1 pair of sampled signal of DSP control board, the method of filtering is that 10 sampled signals are removed maximum and minimum value, asks arithmetic mean with remaining 8 sampled value again;
B, outer voltage are regulated: whether the input voltage sampled value of being judged two-way DC/DC inverter main circuit 6 by the control program of DSP control board 1 reaches limit value, if do not reach limit value, then call the constant voltage program that discharges and recharges and produce the reference current that electric current loop is regulated, if reach limit value, then call the constant current charge-discharge program and produce the reference current that electric current loop is regulated;
C, current inner loop are regulated: the control program by DSP control board 1 compares the reference current of electric current loop and the sample rate current value of input current transducer 4, and produces the duty ratio that drives IGBT conducting, shutoff;
D, produce the PWM waveform: produce the PWM waveform by the control program of DSP control board 1 according to the duty ratio of IGBT conducting, shutoff, drive the IGBT of two-way DC/DC inverter main circuit 6 by IGBT drive circuit 3.
What described outer voltage was regulated, current inner loop is regulated employing is the anti-saturated digital pi regulator of integration.Described control program is the core algorithm program of control method, writes DSP control board 1 in advance.
Be example with the accumulator cell charging and discharging below, method of the present invention be described further:
1, gathers two-way DC/DC inverter main circuit output voltage, charging current and input battery tension by AD;
2, whether the control program detection accumulator voltage by DSP control board 1 reaches limit value, if do not reach limit value, then call the constant voltage program that discharges and recharges and produce the reference current that electric current loop is regulated,, then call the constant current charge-discharge program and produce the reference current that electric current loop is regulated if reach limit value;
3, the duty ratio of utilizing voltage, electric current to produce after overcorrect, the PWM generating unit by DSP control board 1 produces the pwm signal of the two-way DC/DC converter of control.
Claims (8)
1, the control circuit of a kind of non-isolation type bidirectional DC/DC converter, comprise input voltage sensor (2), output voltage sensor (5), DSP control board (1), IGBT drive circuit (3), described input voltage sensor (2) is parallel to the input of two-way DC/DC inverter main circuit (6), output voltage sensor (5) is parallel to the output of two-way DC/DC inverter main circuit (6), described DSP control board (1) respectively with the 3rd terminal of input voltage sensor (2), the 3rd terminal of output voltage sensor (5) and IGBT drive circuit (3) connect, it is characterized in that: described control circuit also comprises input current transducer (4), described input current transducer (4) is connected in series to the input circuit of two-way DC/DC inverter main circuit (6), and the 3rd terminal of input current transducer (4) is connected with DSP control board (1).
2, the control circuit of non-isolation type bidirectional DC according to claim 1/DC converter is characterized in that: described DSP control board (1) is made up of digital signal processor DSP and peripheral circuit.
3, the control circuit of non-isolation type bidirectional DC according to claim 2/DC converter is characterized in that: described peripheral circuit comprises that crystal oscillator, power supply, AD sampling, PWM export isolation.
4, the control circuit of non-isolation type bidirectional DC according to claim 2/DC converter is characterized in that: described digital signal processor DSP is the TMS320LF2407 digital signal processor.
5, the control method of the control circuit of a kind of non-isolation type bidirectional DC/DC converter is characterized in that: may further comprise the steps:
A, sampling: respectively input voltage, output voltage and the input current of two-way DC/DC inverter main circuit (6) are sampled by input voltage sensor (2), output voltage sensor (5), input current transducer (4);
B, outer voltage are regulated: whether the input voltage sampled value of being judged two-way DC/DC inverter main circuit (6) by the control program of DSP control board (1) reaches limit value, if do not reach limit value, then call the constant voltage program that discharges and recharges and produce the reference current that electric current loop is regulated, if reach limit value, then call the constant current charge-discharge program and produce the reference current that electric current loop is regulated;
C, current inner loop are regulated: the control program by DSP control board (1) compares the reference current of electric current loop and the sample rate current value of input current transducer (4), and produces the duty ratio that drives IGBT conducting, shutoff;
D, produce the PWM waveform: produce the PWM waveform by the control program of DSP control board (1) according to the duty ratio of IGBT conducting, shutoff, drive the IGBT of two-way DC/DC inverter main circuit (6) by IGBT drive circuit (3).
6, the control method of the control circuit of non-isolation type bidirectional DC according to claim 5/DC converter is characterized in that: what described outer voltage was regulated, current inner loop is regulated employing is the anti-saturated digital pi regulator of integration.
7, the control method of the control circuit of non-isolation type bidirectional DC according to claim 5/DC converter, it is characterized in that: the described method of sampling is continuous sampling 10 times, by DSP control board (1) sampled signal is carried out digital filtering, the method of filtering is that 10 sampled signals are removed maximum and minimum value, asks arithmetic mean with remaining 8 sampled value again.
8, the control method of the control circuit of non-isolation type bidirectional DC according to claim 5/DC converter is characterized in that: described control program is the core algorithm program of control method, writes DSP control board (1) in advance.
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| CN102723863A (en) * | 2011-03-30 | 2012-10-10 | 上海三菱电梯有限公司 | Non-isolated bi-directional DC-DC converter control method |
| CN102761245A (en) * | 2011-04-26 | 2012-10-31 | 鸿富锦精密工业（深圳）有限公司 | Step-down converter circuit |
| CN103023320A (en) * | 2012-11-23 | 2013-04-03 | 矽力杰半导体技术(杭州)有限公司 | High-efficiency bidirectional direct current converter and control method thereof |
| CN103119840A (en) * | 2010-07-15 | 2013-05-22 | 伍德沃德Ids瑞士股份有限公司 | Bidirectional DC converter |
| CN103267891A (en) * | 2013-05-31 | 2013-08-28 | 重庆大学 | Lossless current detecting circuit based on digital correction |
| CN103378727A (en) * | 2012-04-24 | 2013-10-30 | 比亚迪股份有限公司 | DC/DC for dual-direction constant current and method for controlling dual-direction constant current |
| CN103378728A (en) * | 2012-04-24 | 2013-10-30 | 比亚迪股份有限公司 | DC/DC for dual-direction constant voltage and method for controlling dual-direction constant voltage |
| CN103516213A (en) * | 2013-09-09 | 2014-01-15 | 深圳市佳华利道新技术开发有限公司 | Bidirectional dc-dc converter circuit control system and hybrid power motor vehicle |
| CN104008231A (en) * | 2014-05-08 | 2014-08-27 | 华南理工大学 | Modeling and analyzing method for switching power converter controlled by digital current mode |
| CN104124867A (en) * | 2013-04-26 | 2014-10-29 | 丰郅(上海)新能源科技有限公司 | Two-way direct-current converter topology |
| CN104836437A (en) * | 2015-03-31 | 2015-08-12 | 西安理工大学 | Inductive current prediction and complementation convergent control method used for bidirectional DC/DC converter |
| CN107947540A (en) * | 2017-12-22 | 2018-04-20 | 固纬电子(苏州)有限公司 | Two quadrant energy supply control modules |
| CN110140289A (en) * | 2016-12-29 | 2019-08-16 | 三菱电机株式会社 | Power conversion device |
| CN110209232A (en) * | 2019-05-14 | 2019-09-06 | 中国矿业大学 | A kind of DC Electronic Loads Three-loop control method limiting rail voltage |
| CN110365219A (en) * | 2019-08-16 | 2019-10-22 | 北京机械设备研究所 | A kind of two-way DC/DC circuit |
| CN111459220A (en) * | 2020-04-10 | 2020-07-28 | 西南科技大学 | High-inductance constant-current driving control method for electromagnetic valve |
| CN114172125A (en) * | 2021-11-24 | 2022-03-11 | 北京卫星制造厂有限公司 | Power supply and distribution protection device for solid electronic switch |
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2009
- 2009-01-19 CN CNA2009100102165A patent/CN101478235A/en active Pending
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| CN103119840B (en) * | 2010-07-15 | 2016-06-15 | 伍德沃德Ids瑞士股份有限公司 | Two-way DC actuator |
| CN103119840A (en) * | 2010-07-15 | 2013-05-22 | 伍德沃德Ids瑞士股份有限公司 | Bidirectional DC converter |
| CN102723863A (en) * | 2011-03-30 | 2012-10-10 | 上海三菱电梯有限公司 | Non-isolated bi-directional DC-DC converter control method |
| CN102723863B (en) * | 2011-03-30 | 2014-12-10 | 上海三菱电梯有限公司 | Non-isolated bi-directional DC-DC converter control method |
| CN102761245A (en) * | 2011-04-26 | 2012-10-31 | 鸿富锦精密工业（深圳）有限公司 | Step-down converter circuit |
| CN102761245B (en) * | 2011-04-26 | 2016-06-29 | 国网新疆电力公司电力科学研究院 | Buck conversion circuit |
| CN103378728A (en) * | 2012-04-24 | 2013-10-30 | 比亚迪股份有限公司 | DC/DC for dual-direction constant voltage and method for controlling dual-direction constant voltage |
| CN103378727B (en) * | 2012-04-24 | 2016-04-27 | 比亚迪股份有限公司 | A kind of DC/DC for bidirectional constant and control method thereof |
| CN103378727A (en) * | 2012-04-24 | 2013-10-30 | 比亚迪股份有限公司 | DC/DC for dual-direction constant current and method for controlling dual-direction constant current |
| CN103023320B (en) * | 2012-11-23 | 2014-09-03 | 矽力杰半导体技术(杭州)有限公司 | High-efficiency bidirectional direct current converter and control method thereof |
| CN103023320A (en) * | 2012-11-23 | 2013-04-03 | 矽力杰半导体技术(杭州)有限公司 | High-efficiency bidirectional direct current converter and control method thereof |
| CN104124867A (en) * | 2013-04-26 | 2014-10-29 | 丰郅(上海)新能源科技有限公司 | Two-way direct-current converter topology |
| CN103267891A (en) * | 2013-05-31 | 2013-08-28 | 重庆大学 | Lossless current detecting circuit based on digital correction |
| CN103267891B (en) * | 2013-05-31 | 2015-06-10 | 重庆大学 | Lossless current detecting circuit based on digital correction |
| CN103516213A (en) * | 2013-09-09 | 2014-01-15 | 深圳市佳华利道新技术开发有限公司 | Bidirectional dc-dc converter circuit control system and hybrid power motor vehicle |
| CN103516213B (en) * | 2013-09-09 | 2016-08-31 | 深圳市佳华利道新技术开发有限公司 | Bidirectional DC-DC converter circuit control system and hybrid motor vehicle |
| CN104008231A (en) * | 2014-05-08 | 2014-08-27 | 华南理工大学 | Modeling and analyzing method for switching power converter controlled by digital current mode |
| CN104008231B (en) * | 2014-05-08 | 2017-04-19 | 华南理工大学 | Modeling and analyzing method for switching power converter controlled by digital current mode |
| CN104836437A (en) * | 2015-03-31 | 2015-08-12 | 西安理工大学 | Inductive current prediction and complementation convergent control method used for bidirectional DC/DC converter |
| CN104836437B (en) * | 2015-03-31 | 2017-05-03 | 西安理工大学 | Inductive current prediction and complementation convergent control method used for bidirectional DC/DC converter |
| CN110140289A (en) * | 2016-12-29 | 2019-08-16 | 三菱电机株式会社 | Power conversion device |
| CN110140289B (en) * | 2016-12-29 | 2021-09-17 | 三菱电机株式会社 | Power conversion device |
| CN107947540A (en) * | 2017-12-22 | 2018-04-20 | 固纬电子(苏州)有限公司 | Two quadrant energy supply control modules |
| CN110209232A (en) * | 2019-05-14 | 2019-09-06 | 中国矿业大学 | A kind of DC Electronic Loads Three-loop control method limiting rail voltage |
| CN110365219A (en) * | 2019-08-16 | 2019-10-22 | 北京机械设备研究所 | A kind of two-way DC/DC circuit |
| CN111459220A (en) * | 2020-04-10 | 2020-07-28 | 西南科技大学 | High-inductance constant-current driving control method for electromagnetic valve |
| CN114172125A (en) * | 2021-11-24 | 2022-03-11 | 北京卫星制造厂有限公司 | Power supply and distribution protection device for solid electronic switch |
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