Inertial sensor DC power supply DC / DC module

Abstract

The utility model relates to a direct current power supply DC / DC module of an inertial sensor, which comprises an isolation type bidirectional Cuk converter, a PI controller, a PI self-adaptive fuzzy controller and a PI self-adaptive fuzzy control strategy, and adopts a brand new topological structure. The inertial sensor direct current power supply DC / DC module can quickly output direct current voltage and direct current in a voltage reduction mode by presetting proper proportion and integral control parameters; a PI parameter, a threshold value U and a scaling factor beta parameter are preset, so that an inertial sensor direct current power supply DC / DC module outputs required direct current voltage in a boost mode; meanwhile, the requirements of charging and energy storage on the low-voltage power module side from the high-voltage direct-current bus side and the requirements of discharging and energy releasing on the power module side are met, and bidirectional power conversion between two different levels of direct-current voltages is achieved; and stable operation of the inertial sensor system is ensured.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, in particular to an inertial sensor direct current power supply DC / DC module. Background Art

[0002] An inertial module is a sensor that can measure an object's acceleration, rotation, or both relative to inertial space. It has widespread application in military, aerospace, automotive, and industrial automation fields. However, inertial sensors typically use externally supplied AC power to connect to the AC grid or power local AC loads, while energy storage devices such as inertial sensors are typically directly connected to the DC bus on the DC side of the system. Because the DC bus voltage level must meet the inverter input requirements, it transmits high voltage. However, the terminal voltage of the inertial sensor power module is generally relatively low, so the inertial sensor power module cannot be directly connected to the DC bus. A charge-discharge controller is required to bridge the gap between the power module and the DC bus. This charge-discharge controller must both charge and store energy from the higher-voltage DC bus to the lower-voltage power module, and discharge energy from the power module, enabling bidirectional power conversion between two different DC voltage levels. Summary of the Invention

[0003] In view of this, the utility model provides an inertial sensor DC / DC power supply module, which effectively solves the problem in the prior art that it is unable to simultaneously meet the needs of charging and storing energy from the higher-voltage DC bus side to the lower-voltage power module side, and the needs of discharging energy from the power module side, and is unable to achieve bidirectional power conversion between two different levels of DC voltage.

[0004] To achieve the above object, an inertial sensor DC / DC power supply module includes an isolated bidirectional Cuk converter, a PI controller, and a PI adaptive fuzzy controller, wherein the PI adaptive fuzzy controller includes a signal feedback circuit and a voltage comparator;

[0005] The PI adaptive fuzzy controller sets the output voltage U of the isolated bidirectional Cuk converter to o With the reference voltage signal U ref The deviation between them is divided into two levels: "large" and "small"; when the output voltage U o With the reference voltage signal U ref When the deviation between the two is "large", the inertial sensor DC current DC / DC module operates in a step-down mode with a small duty cycle, and the output of the isolated bidirectional Cuk converter quickly responds to the given reference voltage signal U by setting appropriate PI parameters for the PI controller. ref; When the output voltage U o With the reference voltage signal U ref When the deviation between is “small”, the inertial sensor DC / DC module operates in a boost mode with a large duty cycle, and reduces the control increment output by the PI controller by a preset proportional factor β;

[0006] When the inertial sensor DC / DC module operates in a boost mode with a large duty cycle, one end of the PI controller is connected to an isolated bidirectional Cuk converter, and the isolated bidirectional Cuk converter is connected to the output end and the signal feedback circuit, and the output voltage U of the isolated bidirectional Cuk converter is increased. o Converted to voltage U′ o The other end of the signal feedback circuit is connected to one input end of the voltage comparator, and the other input end of the voltage comparator is connected to the reference voltage input end. The voltage U′ is obtained through the feedback circuit. o With the reference voltage signal U ref An output terminal of the voltage comparator compares the error voltage signal E with the error signal change rate. As input to the PI adaptive fuzzy controller, the PI adaptive fuzzy controller generates the correction value Δk of the proportional coefficient and the integral coefficient in real time p , Δk i As an input quantity to the PI controller, the output end of the voltage comparator is connected to the PI controller, and the error voltage signal E is taken as an input quantity to the PI controller.

[0007] Preferably, when the inertial sensor DC / DC module operates in a step-down mode with a small duty cycle, one end of the PI controller is connected to an isolated bidirectional Cuk converter, and the isolated bidirectional Cuk converter is connected to the output end and the signal feedback circuit, and the output voltage U of the isolated bidirectional Cuk converter is converted to o Converted to voltage U′ o The other end of the signal feedback circuit is connected to one input end of the voltage comparator, and the other input end of the voltage comparator is connected to the reference voltage input end. The voltage U′ is obtained through the feedback circuit. o With the reference voltage signal U ref An error voltage signal E is obtained by comparison, and one output terminal of the voltage comparator sends the error voltage E signal as an input to the PI controller.

[0008] Preferably, the isolated bidirectional Cuk converter includes a first capacitor C1, a second capacitor C2, and a third capacitor C a , the fourth capacitor C b, a first inductor L1, a second inductor L2, a first diode D1, a second diode D2, a first switch tube S1, a second switch tube S2 and a transformer T, one end of the first capacitor C1 is connected to one end of the first inductor L1, and the other end of the first inductor L1 is connected to the third capacitor C a The third capacitor C a The other end of the first switching transistor S1 is connected to one end of the primary winding of the transformer T, the other end of the primary winding of the transformer T is connected to the other end of the first capacitor C1, the source of the first switching transistor S1 is connected to the connection point between the first capacitor C1 and the primary winding of the transformer T, and the drain of the first switching transistor S1 is connected to the first inductor L1 and the third capacitor C a One end of the first diode D1 is connected to the first inductor L1 and the third capacitor C a The other end of the first diode D1 is connected to the connection point of the first capacitor C1 and the primary winding of the transformer T; one end of the second capacitor C2 is connected to one end of the second inductor L2, and the other end of the second inductor L2 is connected to the fourth capacitor C b The fourth capacitor C b The other end of the second switching transistor S2 is connected to one end of the secondary winding of the transformer T, the other end of the secondary winding of the transformer T is connected to the other end of the second capacitor C2, the source of the second switching transistor S2 is connected to the connection point between the second capacitor C2 and the secondary winding of the transformer T, and the drain of the second switching transistor S2 is connected to the second inductor L2 and the fourth capacitor C b One end of the second diode D2 is connected to the second inductor L2 and the fourth capacitor C b The other end of the second diode D2 is connected to the connection point of the second capacitor C2 and the secondary winding of the transformer T.

[0009] Preferably, the PI controller needs to preset proportional and integral control parameters, calculate the control amount, and then adjust the duty cycle α according to the calculated amount.

[0010] Compared with the prior art, the beneficial effects of the present invention are:

[0011] 1. This utility model selects different closed-loop control strategies. When the inertial sensor DC / DC power supply module operates in the step-down mode with a small duty cycle, the traditional PI control strategy is adopted. When the inertial sensor DC / DC power supply module operates in the boost mode with a large duty cycle, the system is in a strongly nonlinear state. By comparing and analyzing the control strategies of fuzzy control, the more suitable improved PI control strategy is adopted. This is simpler and more reliable, effectively improving the nonlinear state of the inertial sensor system, outputting stable DC voltage and DC current, and ensuring the stable operation of the inertial sensor system.

[0012] 2. The topology of the isolated bidirectional Culk converter used in the present invention has inductors on both the input and output sides, resulting in small current pulsations, which is beneficial to the design of the filter. In addition, power can be transferred from the input side to the output side throughout the switching cycle, resulting in high efficiency.

[0013] 3. The PI controller used in the present invention has a simple structure, high reliability and strong robustness.

[0014] 4. The utility model presets appropriate proportional and integral control parameters, and the PI controller can calculate the control quantity. The duty cycle α is adjusted by the control quantity, so that the DC / DC module of the substation can output quickly and follow the given reference signal without static error, thereby realizing closed-loop control of the DC / DC module of the inertial sensor in the buck mode.

[0015] 5. Although the control strategy adopted by the present invention is not as universal as the fuzzy PI control, it reduces the control increment of the controller output by a proportional factor β, eliminating the complex construction process of the fuzzy PI controller and reducing the amount of calculation. It only needs to preset the PI parameters, threshold U, and proportional factor β parameters. It is simpler, more intuitive and more suitable for the isolated bidirectional Cuk converter boost control. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a topological diagram of the isolated bidirectional Cuk converter of the utility model;

[0017] Figure 2 This is the closed-loop control diagram of the isolated bidirectional Cuk converter in buck mode of the utility model;

[0018] Figure 3 This is the fuzzy adaptive PI controller diagram of the isolated bidirectional Cuk converter of the utility model;

[0019] Figure 4 This is the logic diagram of the fuzzy adaptive PI control of this utility model. DETAILED DESCRIPTION

[0020] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation method, structure, characteristics and effects of the present invention in combination with the accompanying drawings and preferred embodiments.

[0021] The utility model provides the following technical solutions:

[0022] An inertial sensor DC / DC power supply module includes an isolated bidirectional Cuk converter, a PI controller, and a PI adaptive fuzzy controller, wherein the PI adaptive fuzzy controller includes a signal feedback circuit and a voltage comparator;

[0023] As the charge and discharge controller for the power module in the inertial sensor system, the isolated bidirectional Cuk converter acts as a bridge for bidirectional energy transfer between the DC bus and the power module. It can achieve optimal energy management and reasonable scheduling in the inertial sensor system and is an indispensable component of the entire inertial sensor system.

[0024] When the inertial sensor DC / DC power supply module operates in buck mode, the nonlinear relationship between the gain k2 and the duty cycle α of the isolated bidirectional Cuk converter is weak. In this case, the relationship between the gain k2 and the duty cycle α can be approximately regarded as a linear relationship, so it can be controlled according to the control strategy of the linear system.

[0025] The PI adaptive fuzzy controller sets the output voltage U of the isolated bidirectional Cuk converter to o With the reference voltage signal U ref The deviation between them is divided into two levels: "large" and "small"; when the output voltage U o With the reference voltage signal U ref When the deviation between them is "large", there is no need to consider the overshoot and oscillation problems of the converter for the time being. The inertial sensor DC current DC / DC module works in the buck mode with a small duty cycle. Therefore, by setting appropriate PI parameters for the PI controller, the output of the isolated bidirectional Cuk converter quickly responds to the given reference voltage signal U ref ; When the output voltage U o With the reference voltage signal U ref When the deviation between the two is "small", the inertial sensor DC current DC / DC module operates in the boost mode with a large duty cycle. It can be considered that the output of the isolated bidirectional Cuk converter is close to the given expected value. At this time, the isolated bidirectional Cuk converter operates in the strong nonlinear region. To prevent the output of the isolated bidirectional Cuk converter from being too sensitive to the control action, causing large overshoot and oscillation, the control increment of the PI controller output is reduced by the preset proportional factor β.

[0026] When the inertial sensor DC current DC / DC module operates in a boost mode with a large duty cycle, one end of the PI controller is connected to the isolated bidirectional Cuk converter, and the isolated bidirectional Cuk converter is connected to the output end and the signal feedback circuit to increase the output voltage U o Converted to voltage U′ O The other end of the signal feedback circuit is connected to one input end of the voltage comparator, and the other input end of the voltage comparator is connected to the reference voltage input end. The voltage U′ is obtained through the feedback circuit. O With the reference voltage signal Uref The error voltage signal E is obtained by comparison. One output terminal of the voltage comparator converts the error voltage signal E into the error signal change rate. As input to the PI adaptive fuzzy controller, the PI adaptive fuzzy controller generates the correction value Δk of the proportional coefficient and the integral coefficient in real time p , Δk i As an input to the PI controller, the output end of the voltage comparator is connected to the PI controller, and the error voltage signal E is taken as an input to the PI controller.

[0027] When the inertial sensor DC current DC / DC module operates in a step-down mode with a small duty cycle, one end of the PI controller is connected to the isolated bidirectional Cuk converter, and the isolated bidirectional Cuk converter is connected to the output end and the signal feedback circuit to convert the output voltage U o Converted to voltage U′ O The other end of the signal feedback circuit is connected to one input end of the voltage comparator, and the other input end of the voltage comparator is connected to the reference voltage input end. The voltage U′ is obtained through the feedback circuit. O With the reference voltage signal U ref The error voltage signal E is obtained by comparison, and one output end of the voltage comparator sends the error voltage E signal as input to the PI controller.

[0028] The isolated Cuk converter not only achieves electrical isolation between the input and output sides, but also retains all the features of the basic Cuk converter. However, the isolated Cuk converter can only perform unidirectional power conversion from one side to the other, which cannot meet the application scenarios of bidirectional power flow. Based on the isolated Cuk converter, a power diode is connected in anti-parallel at both ends of the insulated gate bipolar transistor, and an insulated gate bipolar transistor is connected in anti-parallel at both ends of the diode.

[0029] The topology diagram of the isolated bidirectional Cuk converter is as follows: Figure 1 As shown, it includes a first capacitor C1, a second capacitor C2, and a third capacitor C a , the fourth capacitor C b , the first inductor L1, the second inductor L2, the first diode D1, the second diode D2, the first switch tube S1, the second switch tube S2 and the transformer T, one end of the first capacitor C1 is connected to one end of the first inductor L1, and the other end of the first inductor L1 is connected to the third capacitor C a The third capacitor C a The other end of the first switching transistor S1 is connected to one end of the primary winding of the transformer T, the other end of the primary winding of the transformer T is connected to the other end of the first capacitor C1, the source of the first switching transistor S1 is connected to the connection point of the first capacitor C1 and the primary winding of the transformer T, and the drain of the first switching transistor S1 is connected to the first inductor L1 and the third capacitor Ca One end of the first diode D1 is connected to the first inductor L1 and the third capacitor C a The other end of the first diode D1 is connected to the connection point of the first capacitor C1 and the primary winding of the transformer T; one end of the second capacitor C2 is connected to one end of the second inductor L2, and the other end of the second inductor L2 is connected to the fourth capacitor C b The fourth capacitor C b The other end of the second switching transistor S2 is connected to one end of the secondary winding of the transformer T, the other end of the secondary winding of the transformer T is connected to the other end of the second capacitor C2, the source of the second switching transistor S2 is connected to the connection point of the second capacitor C2 and the secondary winding of the transformer T, and the drain of the second switching transistor S2 is connected to the second inductor L2 and the fourth capacitor C b One end of the second diode D2 is connected to the second inductor L2 and the fourth capacitor C b The other end of the second diode D2 is connected to the connection point of the second capacitor C2 and the secondary winding of the transformer T;

[0030] When the isolated bidirectional Cuk converter's U1 is used as the input voltage and U2 is used as the output voltage, after the isolated bidirectional Cuk converter enters the steady state, if the switch tube S1 is turned on, the input voltage U1 charges the input side inductor L1. Under the coupling effect of the transformer, the capacitor C a with C b At the same time, the output side is discharged to provide output power and the output side inductor L2 is charged. When the switch tube S1 is turned off, the inductor L1 is discharged and the capacitor C is charged together with the input voltage. a The capacitor C is charged through the coupling effect of the transformer. b When the isolated bidirectional Cuk converter U2 is used as the input voltage and U1 is used as the output voltage, after the isolated bidirectional Cuk converter enters the steady state, if the switch tube S2 is turned on, the input voltage U2 charges the input side inductor L2. Under the coupling effect of the transformer, the capacitor C a with C b At the same time, the output side is discharged to provide output power and the output side inductor L1 is charged. When the switch tube S2 is turned off, the inductor L2 is discharged and the capacitor C is charged together with the input voltage. b The capacitor C is charged through the coupling effect of the transformer. a Charging, at this time the inductor L1 is discharged to provide output; in this topology, there are inductors on both the input and output sides, the current pulsation is small, which is conducive to the design of the filter, and power can be transferred from the input side to the output side throughout the switching cycle, with high efficiency, which is the best DC converter topology;

[0031] The PI controller needs to preset proportional and integral control parameters, calculate the control quantity, and then adjust the duty cycle α according to the calculated quantity.

[0032] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An inertial sensor DC / DC power supply module, characterized in that: It includes an isolated bidirectional Cuk converter, a PI controller, and a PI adaptive fuzzy controller, wherein the PI adaptive fuzzy controller includes a signal feedback circuit and a voltage comparator; The PI adaptive fuzzy controller presets a threshold , the output voltage of the isolated bidirectional Cuk converter With reference voltage signal The deviation between them is divided into two levels: "large" and "small"; when the output voltage of the isolated bidirectional Cuk converter With reference voltage signal When the deviation between them is "large", the inertial sensor DC current DC / DC module works in the buck mode with a small duty cycle. By setting appropriate PI parameters for the PI controller, the output of the isolated bidirectional Cuk converter quickly responds to the given reference voltage signal. ; When the output voltage of the isolated bidirectional Cuk converter With reference voltage signal When the deviation between the two is "small", the inertial sensor DC current DC / DC module operates in a boost mode with a large duty cycle, and the preset proportional factor Reduce the control increment of the PI controller output; When the inertial sensor DC / DC module operates in a boost mode with a large duty cycle, one end of the PI controller is connected to an isolated bidirectional Cuk converter, and the isolated bidirectional Cuk converter is connected to the output end and the signal feedback circuit, and the output voltage of the isolated bidirectional Cuk converter is increased. Convert to voltage The other end of the signal feedback circuit is connected to one input end of the voltage comparator, and the other input end of the voltage comparator is connected to the reference voltage input end. The voltage is obtained through the feedback circuit. With reference voltage signal Compare to get the error voltage signal , one output terminal of the voltage comparator will convert the error voltage signal The rate of change of the error signal As input to the PI adaptive fuzzy controller, the PI adaptive fuzzy controller generates corrections to the proportional coefficient and integral coefficient in real time. 、 As the input to the PI controller, the voltage comparator output is connected to the PI controller and the error voltage signal As input to the PI controller.

2. The inertial sensor DC / DC power supply module according to claim 1, characterized in that: When the inertial sensor DC / DC module operates in a step-down mode with a small duty cycle, one end of the PI controller is connected to the isolated bidirectional Cuk converter, and the isolated bidirectional Cuk converter is connected to the output end and the signal feedback circuit, and the output voltage of the isolated bidirectional Cuk converter is converted to Convert to voltage The other end of the signal feedback circuit is connected to one input end of the voltage comparator, and the other input end of the voltage comparator is connected to the reference voltage input end. The voltage is obtained through the feedback circuit. With reference voltage signal Compare to get the error voltage signal , one output of the voltage comparator will convert the error voltage The signal is used as input to the PI controller.

3. The inertial sensor DC / DC power supply module according to claim 1, characterized in that: The isolated bidirectional Cuk converter includes a first capacitor , the second capacitor , the third capacitor , the fourth capacitor , first inductor , the second inductor , the first diode , the second diode , the first switch tube , the second switch tube and transformer T, the first capacitor One end of the first inductor One end of the first inductor is connected to The other end of the third capacitor The third capacitor The other end of the primary winding of the transformer T is connected to one end of the primary winding of the transformer T, and the other end of the primary winding of the transformer T is connected to the first capacitor The other end of the first switch is connected to The source and the first capacitor The first switch is connected to the connection point of the primary winding of the transformer T. The drain and the first inductor and the third capacitor The connection point of the first diode is connected One end of the first inductor and the third capacitor The connection point of the first diode is connected The other end of the first capacitor and connected to the connection point of the primary winding of the transformer T; the second capacitor One end of the second inductor One end of the second inductor is connected to The other end of the fourth capacitor The fourth capacitor The other end of the secondary winding of the transformer T is connected to one end of the secondary winding of the transformer T, and the other end of the secondary winding of the transformer T is connected to the second capacitor The other end of the second switch is connected to The source and the second capacitor The second switch is connected to the connection point of the secondary winding of the transformer T. The drain and the second inductor and the fourth capacitor The connection point of the second diode is connected One end of the second inductor and the fourth capacitor The connection point of the second diode is connected The other end of the second capacitor Connected to the connection point of the secondary winding of transformer T.

Images