CN113659804B - System for restraining drift amount of high-low temperature constant current point for aerospace - Google Patents
System for restraining drift amount of high-low temperature constant current point for aerospace Download PDFInfo
- Publication number
- CN113659804B CN113659804B CN202110932466.5A CN202110932466A CN113659804B CN 113659804 B CN113659804 B CN 113659804B CN 202110932466 A CN202110932466 A CN 202110932466A CN 113659804 B CN113659804 B CN 113659804B
- Authority
- CN
- China
- Prior art keywords
- constant current
- resistor
- current
- power supply
- sampling
- 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
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Amplifiers (AREA)
Abstract
The invention discloses a system for inhibiting high-low temperature constant current point drift amount for aerospace, which comprises: the constant current source power conversion front stage, the filter inductor L10, the filter capacitor C10, the power load, the sampling resistor R31, the differential current sampling circuit, the constant current function control circuit and the PWM control chip; the filtering inductor L10, the power load and the sampling resistor R31 are sequentially connected in series and then connected with a front stage of constant current source power conversion; the filter capacitor C10 is arranged in parallel with the electric load; the differential current sampling circuit collects the voltage on the sampling resistor R31; the differential current sampling circuit, the constant current function control circuit and the PWM control chip are sequentially connected in series and then connected with a constant current source power conversion front stage. The invention discloses a system for inhibiting the drift amount of a high-low temperature constant current point through aerospace, which aims to reduce the drift amount of the constant current point of an aerospace power supply in a temperature alternating environment, improve the control precision of the aerospace power supply on the constant current point and ensure the normal operation of a spacecraft on orbit.
Description
Technical Field
The invention belongs to the technical field of space power supplies, and particularly relates to a system for inhibiting high-low temperature constant current point drift amount for aerospace.
Background
The power supply has the function of constant current or constant current of a power distribution power supply in the technical field of space power supply. For example: and the charging regulator stores solar array energy in the storage battery pack in a constant-current constant-voltage charging mode during illumination, and the charging constant-voltage point and the charging constant-current point are determined by ground personnel to select a charging gear. For another example, a satellite laser load distributor is provided with a large capacitor in a load power amplifier driver, the laser load needs to release a large amount of energy in a short time, the laser load distributor needs to timely supplement energy for the large capacitor of the load power amplifier driver in a charging period, and in order not to cause too large current fluctuation on a platform bus, the distributor needs to have constant current output capacity, and a constant current point of the distributor is controlled by an external constant current signal provided by a laser subsystem.
The existing constant current control technology for space is the constant current control technology, and the general principle is as follows: 1. collecting a sampling signal of the current at the output end of the bus; 2. based on the constant current reference and the output current sampling signal, generating a corresponding pulse width control signal through the operation of the constant current function control circuit; 3. the pulse width control signal acts on a front-stage power tube of the power converter to modulate the output current, so that the purpose of constant current output is achieved. The control accuracy of the aerospace power supply to the constant current point mainly depends on the accuracy of the output current sampling signal.
At present, the general bus output current sampling circuit mainly comprises: 1. the mirror current source sampling circuit is used for placing a current sampling resistor at the positive electrode of the bus output, achieving the purpose of high-precision sampling of output current through a triode pair tube (usually an inlet device 2N 3810) with consistent characteristics, and is suitable for application occasions where the output bus is stable. 2. The differential current sampling circuit is used for placing a current sampling resistor on a bus output loop, and a differential amplifying circuit forms a current sampling signal through a voltage signal on the current sampling resistor, so that whether the output bus is stable or not does not influence the use of the circuit, but the phenomenon of large drift of high-low temperature constant current points exists in an environmental test (a thermal cycle test or a thermal vacuum test) with temperature alternation of an aerospace power converter applying the differential current sampling circuit, so that the precision of aerospace high-precision constant current control is seriously restricted, and even the on-orbit normal operation of a spacecraft is influenced.
Disclosure of Invention
The technical solution of the invention is as follows: the system for inhibiting the drift amount of the high-low temperature constant current point for aerospace is provided, and aims to reduce the drift amount of the constant current point of the power supply for aerospace in a temperature alternating environment, improve the control precision of the power supply for aerospace on the constant current point and ensure the normal operation of a spacecraft in orbit.
In order to solve the technical problems, the invention discloses a system for inhibiting the drift amount of high and low temperature constant current points for aerospace, which comprises the following components: the constant current source power conversion front stage, the filter inductor L10, the filter capacitor C10, the power load, the sampling resistor R31, the differential current sampling circuit, the constant current function control circuit and the PWM control chip;
the filtering inductor L10, the power load and the sampling resistor R31 are sequentially connected in series and then connected with a front stage of constant current source power conversion; one end of the filter inductor L10 is connected with the front stage of constant current source power conversion, and the other end is connected with one end of an electric load; the other end of the electric load is connected with one end of the sampling resistor R31; the other end of the sampling resistor R31 is connected with a constant current source power conversion front stage;
the filter capacitor C10 is arranged in parallel with the electric load;
two sampling ends of the differential current sampling circuit are respectively connected with two ends of the sampling resistor R31 to acquire and obtain the voltage on the sampling resistor R31, so as to realize the sampling of the output current;
the differential current sampling circuit, the constant current function control circuit and the PWM control chip are sequentially connected in series and then connected with a constant current source power conversion front stage; the output end of the differential current sampling circuit is connected with one end of the constant current function control circuit; the other end of the constant current function control circuit is connected with one end of the PWM control chip; the other end of the PWM control chip is connected with a constant current source power conversion front stage.
In the system for inhibiting the drift amount of the high-low temperature constant current points for aerospace, the input power is modulated, rectified and converted by a power conversion front stage of the constant current source, and the power supply current is output; the power supply current supplies power to the power utilization load through the filter inductor L10 and the filter capacitor C10; the output current of the power utilization load flows back to the power conversion front stage of the constant current source through the power output loop; the sampling resistor R31 is arranged on the power output loop and is used for representing the output current by adopting a tiny voltage signal.
In the system for suppressing the drift amount of the high-low temperature constant current point for aerospace,
the differential current sampling circuit amplifies and samples a micro voltage signal on the sampling resistor R31 to obtain a current sampling signal, and the current sampling signal is sent to the constant current function control circuit;
the constant current function control circuit performs proportional integration on the constant current reference signal and the current sampling signal to obtain an error amplification signal, and sends the error amplification signal to the PWM control chip;
the PWM control chip generates a pulse width control signal according to the comparison result of the error amplification signal and the internal triangular wave, and sends the pulse width control signal to the constant current source power conversion front stage, so that the constant current source power conversion front stage adjusts the output power supply current according to the pulse width control signal, and the constant power supply current is ensured to be output by the constant current source power conversion front stage according to the constant current reference signal.
In the above system for suppressing the drift amount of the high-low temperature constant current point for aerospace, the filter inductance L10 is: microhenry-millihenry inductance and filter capacitor C10 is: the micro-method-milli-method capacitance and the sampling resistor R31 are as follows: milliohm-level resistance.
In the above system for suppressing the drift amount of the high-low temperature constant current point for aerospace, the differential current sampling circuit includes: the high-speed operational amplifier N1, a power supply resistor R81, a positive phase input resistor R82, a negative phase input resistor R83, a differential amplifying resistor R73, a differential amplifying resistor R74, a power supply Vcc and a power supply filter capacitor C44;
one end of the sampling resistor R31 is connected with the negative phase input resistor R83 and then connected with the negative phase input end of the high-speed operational amplifier N1, and the other end of the sampling resistor R31 is connected with the positive phase input resistor R82 and then connected with the positive phase input end of the high-speed operational amplifier N1;
the differential amplifying resistor R73 is connected in parallel with the negative phase input end and the output end of the high-speed operational amplifier N1;
the differential amplifying resistor R74 is connected in parallel with the non-inverting input end of the high-speed operational amplifier N1 and the SGND;
the power supply Vcc is connected in series with a power supply resistor R81 and a power supply filter capacitor C44 and then connected with SGND;
the g pin of the high-speed operational amplifier N1 is connected with the common end of the power supply resistor R81 and the power supply filter capacitor C44; the g pin of the high-speed operational amplifier N1 is as follows: the chip supplies power to the positive terminal.
In the system for inhibiting the drift amount of the high-low temperature constant current points for aerospace, the resistance values of the positive phase input resistor R82 and the negative phase input resistor R83 are consistent, and are kiloohm resistors; the resistance values of the differential amplifying resistor R73 and the differential amplifying resistor R74 are identical, and the differential amplifying resistor R73 is a resistor of the order of kilohms to hundred kilohms; the power supply Vcc is a +12V power supply; the high-speed operational amplifier N1 is powered by a power supply Vcc single power supply.
In the system for suppressing the drift amount of the high-low temperature constant current points for aerospace, when the positive phase input and the negative phase input of the differential current sampling circuit are the same, the differential current sampling circuit has output; the output of the differential current sampling circuit is 0 by adding an offset voltage to the positive and negative phase inputs of the differential current sampling circuit.
In the above-described system for suppressing the amount of drift of the high-low temperature constant current point for aerospace, the magnitude of the offset voltage changes with a change in temperature, and the amount of drift of the offset voltage is referred to as Δvos.
In the system for suppressing the drift amount of the high-low temperature constant current point for aerospace,
under normal temperature, the output voltage V of the differential current sampling circuit Collecting The method comprises the following steps: v (V) Collecting =kx (i×r+vos); under the condition of normal temperature condition and constant current output, the constant current reference signal V1 is: v1=kx (i×r+vos); wherein K represents the amplification factor of the differential current sampling circuit, k= R73/R83; vos represents an offset voltage value under normal temperature conditions; i represents the value of the current flowing through the sampling resistor R31; r represents the resistance value of the sampling resistor R31; i represents a current value of a constant power supply current output by a power conversion front stage of the constant current source; at normal temperature, Δvos=0;
under the condition of temperature alternating condition and constant current output, the constant current reference signal V1 is: v1=kx (i×r+vos+Δvos); when delta Vos is positive, the output of the differential current sampling circuit is larger, so that the constant power supply current output by the power conversion front stage of the constant current source is smaller; when delta Vos is negative, the output of the differential current sampling circuit is smaller, so that the constant supply current output by the power conversion front stage of the constant current source is larger; wherein, under the condition of temperature alternation, Δvos=vos High height Or Vos Low and low Subtracting Vos, vos High height Representing offset voltage value, vos under high temperature condition Low and low Representing offset voltage values under low temperature conditions.
In the system for suppressing the drift amount of the high-low temperature constant current point for aerospace,
under normal temperature conditions, the constant current reference signal V1 is: k× (I) 1 ×R+Vos)；
Under the high/low temperature condition, the constant current reference signal V1 is: k× (I) 2 ×R+Vos+△Vos)；
When the constant current reference signal V1 is constant, the amplification factor K of the differential current sampling circuit is constant, and the resistance value R of the sampling resistor R31 is constant, there are: - Δvos=r×Δi=r× (I 2 －I 1 )；
Wherein I is 1 Represents constant current point at normal temperature, I 2 Shows constant current point at high/low temperature, and DeltaI shows drift amount of the high/low temperature constant current point.
The invention has the following advantages:
(1) The invention discloses a system for inhibiting the drift amount of high and low temperature constant current points for aerospace, which can use a differential current sampling circuit with simple structure, wide application range and small device voltage and current stress to replace a mirror current source sampling circuit with complex structure, narrow application range and large device voltage and current stress on the premise of ensuring the control precision of constant current points. At present, a core device of a mirror image current source sampling circuit is 2N3810 (a triode pair tube is an imported device), and a domestic device cannot realize accurate conversion due to poor consistency of the triode pair tube. The sampling circuits of the invention all adopt domestic devices.
(2) The invention discloses a system for inhibiting high-low temperature constant current point drift amount for aerospace, which can realize high-precision control of a constant current point by an aerospace power supply by selecting a high-speed operational amplifier with small high-low temperature offset voltage drift amount and increasing the resistance value of a current sampling resistor within a design allowable range, has strong operability and simple realization path, and has good effect.
Drawings
FIG. 1 is a schematic circuit diagram of a system for suppressing drift of high and low temperature constant current points for aerospace according to an embodiment of the present invention;
fig. 2 is a schematic circuit diagram of a differential current sampling circuit according to an embodiment of the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the embodiments of the present invention disclosed herein will be described in further detail with reference to the accompanying drawings.
As shown in fig. 1, in this embodiment, the system for suppressing the drift amount of the high-low temperature constant current point for aerospace comprises: the constant current source power conversion front stage, a filter inductance L10, a filter capacitance C10, an electric load, a sampling resistor R31, a differential current sampling circuit, a constant current function control circuit and a PWM control chip. The filter inductor L10, the power load and the sampling resistor R31 are sequentially connected in series and then connected with a constant current source power conversion front stage; one end of the filter inductor L10 is connected with the front stage of constant current source power conversion, and the other end is connected with one end of an electric load; the other end of the electric load is connected with one end of the sampling resistor R31; the other end of the sampling resistor R31 is connected with a constant current source power conversion front stage. The filter capacitor C10 is arranged in parallel with the electric load. The two sampling ends of the differential current sampling circuit are respectively connected with the two ends of the sampling resistor R31 to acquire the voltage on the sampling resistor R31, so as to realize the sampling of the output current. The differential current sampling circuit, the constant current function control circuit and the PWM control chip are sequentially connected in series and then connected with a constant current source power conversion front stage; the output end of the differential current sampling circuit is connected with one end of the constant current function control circuit; the other end of the constant current function control circuit is connected with one end of the PWM control chip; the other end of the PWM control chip is connected with a constant current source power conversion front stage.
In this embodiment, the constant current source power conversion pre-stage modulates, rectifies, and converts the input power to output a constant supply current; the power supply current is an electric load through the filter inductor L10 and the filter capacitor C10; the output current of the electric load flows back to the power conversion front stage of the constant current source through the power output loop. The sampling resistor R31 is arranged on the power output loop and is used for representing the output current by adopting a tiny voltage signal.
Further, the differential current sampling circuit is configured to amplify and sample the micro voltage signal on the sampling resistor R31 to obtain a current sampling signal, and send the current sampling signal to the constant current function control circuit. And the constant current function control circuit is used for performing proportional integration on the constant current reference signal and the current sampling signal to obtain an error amplification signal, and transmitting the error amplification signal to the PWM control chip. And the PWM control chip is used for generating a pulse width control signal according to the comparison result of the error amplification signal and the internal triangular wave and sending the pulse width control signal to the constant current source power conversion front stage so that the constant current source power conversion front stage can adjust the output power supply current according to the pulse width control signal and ensure that the constant current source power conversion front stage outputs constant power supply current according to the constant current reference signal.
In this embodiment, as shown in fig. 2, the differential current sampling circuit may specifically include: the high-speed operational amplifier N1, a power supply resistor R81, a positive phase input resistor R82, a negative phase input resistor R83, a differential amplifying resistor R73, a differential amplifying resistor R74, a power supply Vcc and a power supply filter capacitor C44. One end of the sampling resistor R31 is connected with the negative phase input resistor R83 and then connected to the negative phase input end of the high-speed operational amplifier N1, and the other end of the sampling resistor R31 is connected with the positive phase input resistor R82 and then connected to the positive phase input end of the high-speed operational amplifier N1. The differential amplifying resistor R73 is connected in parallel to the negative phase input end and the output end of the high-speed operational amplifier N1, the differential amplifying resistor R74 is connected in parallel to the positive phase input end and the SGND of the high-speed operational amplifier N1, and the power supply Vcc is connected in series with the power supply resistor R81 and the power supply filter capacitor C44 and then connected to the SGND. The g pin of the high-speed operational amplifier N1 is connected with the common end of the power supply resistor R81 and the power supply filter capacitor C44; the g pin of the high-speed operational amplifier N1 is as follows: the chip supplies power to the positive terminal.
In this embodiment, the filter inductor L10 may be a microhenry-millihenry inductor, the filter capacitor C10 may be a microfarad-millifarad capacitor, and the sampling resistor R31 may be a milliohm resistor. The positive phase input resistor R82 and the negative phase input resistor R83 have the same resistance value and are kiloohm resistors; the resistance values of the differential amplifying resistor R73 and the differential amplifying resistor R74 are identical, and the differential amplifying resistor R73 is a resistor of the order of kilohms to hundred kilohms; the power supply Vcc is a +12V power supply; the high-speed operational amplifier N1 is powered by a power supply Vcc single power supply.
In this embodiment, the high-speed operational amplifier N1 has an output when the positive and negative phase inputs of the differential current sampling circuit are the same due to the intrinsic characteristics, and in order to make the differential current sampling circuit output 0, a dc voltage, i.e., offset voltage Vos, needs to be applied to the positive and negative phase inputs of the differential current sampling circuit, in units of mv. The offset voltage varies with the temperature, and the offset voltage drift amount is referred to as Δvos (unit: mv). The offset voltage Vos can be provided by the manufacturer with corresponding data, and the measurement method is well known in the art.
Under normal temperature, the output voltage V of the differential current sampling circuit Collecting The method comprises the following steps: v (V) Collecting ＝K×(i×R+Vos)。
Under the condition of normal temperature condition and constant current output, the constant current reference signal V1 is: v1=k× (i×r+vos).
Under the condition of temperature alternating condition and constant current output, the constant current reference signal V1 is: v1=kx (i×r+vos+Δvos).
Wherein K represents the amplification factor of the differential current sampling circuit, k= R73/R83; vos represents an offset voltage value under normal temperature conditions; i represents the value of the current flowing through the sampling resistor R31; r represents the resistance value of the sampling resistor R31; i represents a current value of a constant power supply current output by a power conversion front stage of the constant current source; at normal temperature, Δvos=0.
Preferably, when delta Vos is positive, the output of the differential current sampling circuit is larger, so that the constant power supply current output by the power conversion front stage of the constant current source is smaller; when DeltaVos is negative, the output of the differential current sampling circuit is smaller, so that the constant supply current output by the power conversion front stage of the constant current source is larger. Wherein, under the condition of temperature alternation, Δvos=vos High height Or Vos Low and low Subtracting Vos, vos High height Representing offset voltage value, vos under high temperature condition Low and low Representing offset voltage values under low temperature conditions.
It follows that there are:
under normal temperature conditions, the constant current reference signal V1 is: k× (I) 1 ×R+Vos)。
Under the high/low temperature condition, the constant current reference signal V1 is: k× (I) 2 ×R+Vos+△Vos)。
Therefore, when the constant current reference signal V1 is constant, the amplification factor K of the differential current sampling circuit is constant, and the resistance value R of the sampling resistor R31 is constant, there are: - Δvos=r×Δi=r× (I 2 －I 1 ). Wherein I is 1 Represents constant current point at normal temperature, I 2 Shows constant current point at high/low temperature, and DeltaI shows drift amount of the high/low temperature constant current point.
It can be seen that the high/low temperature constant current point drift amount Δi is proportional to the absolute value abs (Δvos) of the offset voltage drift amount, and inversely proportional to the resistance value R of the sampling resistor R31. Therefore, in the system for suppressing the high/low temperature constant current point drift amount for aerospace disclosed in the present embodiment, the high/low temperature constant current point drift amount can be suppressed by:
1) High-speed operational amplifier N1 with small offset voltage drift of high and low temperature selection
2) The resistance value of the sampling resistor R31 is increased within a design allowable range in consideration of the consumption limit of the sampling resistor R31, the conversion efficiency limit of the entire circuit, and the like.
For example, example 1: taking a certain type of single machine development process as an example, the resistance value of the selected current sampling resistor R31 is an SMT-3W-5mΩ resistor with high precision and low temperature drift, and the resistor power consumption is about 5/1000 x 2.5 x 2.5=0.03W and is far less than 1.5W (50% of rated power consumption) and far less than 0.5W. The high-speed operational amplifier N1 is a 7F3140 chip, the chip serial number is 170, and the parameters of the serial number chip are shown in Table 1:
| chip serial number | High temperature delta Vos (mv) | Low temperature delta Vos (mv) |
| 170 | -2.285 | 3.9 |
TABLE 1 7F3140 chip basic parameter schematic table with chip number 170
In table 1, high temperature Δvos=vos High height Vos, low temperature Δvos=vos Low and low -Vos。
In environmental test with alternating temperature, such as thermal cycle test or thermal vacuum test, the high and low temperature current limiting points are greatly changed, as shown in table 2:
TABLE 2 schematic table of current limiting point values in high and low temperature environments
As can be seen from Table 2, the variation of the high-temperature current limiting value is 0.457A, the variation of the low-temperature current limiting value is-0.78A, the drift of the high-temperature current limiting point and the low-temperature current limiting point reaches 31%, and the on-orbit reliable and safe operation of the spacecraft is seriously affected.
In example 1, the maximum current limit point drift amount Δi occurs at low temperature, which is 0.78A, and the maximum current limit point drift amount Δi in example 1 is to be reduced to within 0.05A. The scheme of the invention is as follows: and in the design allowable range (two conditions are met, namely a, resistance power consumption I.I.R is required to be smaller than 50% of resistance rated power consumption, and b, the power consumption I.I.R of the patch type current sampling resistor for aerospace is required to be smaller than 0.5W, wherein I is a current effective value passing through the current sampling resistor, R is a current sampling resistor resistance value), the current sampling resistor resistance value is increased, and a high-speed operational amplifier with small high-low temperature offset voltage drift amount is selected.
From the formula Δvos=r×Δi, the optimization conditions for a 16-fold reduction in Δi (0.78A/0.05A) are: 1. increasing the resistance R by a factor of 4 (20 mΩ); 2. the absolute value of ΔVos is reduced below 4 times (0.975 mv), specifically:
1. the resistance value of the current sampling resistor R31 is selected as an SMT-3W-20mΩ resistor with high precision and low temperature drift, and the resistor power consumption is about 20/1000 x 2.5 x 2.5=0.12W and is far smaller than 1.5W (50% of rated power consumption) and smaller than 0.5W;
2. the selected high-speed operational amplifier N1 is a 7F3140 chip, the chip serial number is 71, and the parameters of the serial number chip are shown in Table 3:
| chip serial number | High temperature delta Vos (mv) | Low temperature delta Vos (mv) |
| 71 | -0.33 | 0.15 |
TABLE 3 schematic representation of basic parameters of 7F3140 chip with chip number 71
In Table 3, the absolute value of high temperature DeltaVos or low temperature DeltaVos is less than 0.975mv, which can meet the optimization requirement.
An environmental test was performed as in example 1 and the current limit point in the high and low temperature environment was recorded as shown in table 4:
TABLE 4 schematic table of current limiting point values in high and low temperature environments
As can be seen from table 4, the high-temperature current limiting value variation is 0.03A, the low-temperature current limiting value variation is-0.012A, the high-temperature current limiting point drift amount and the low-temperature current limiting point drift amount are both less than 0.05A, and the maximum high-temperature current limiting point drift amount and the low-temperature current limiting point drift amount are 1.2%, which is obviously improved compared with example 1.
Although the present invention has been described in terms of the preferred embodiments, it is not intended to be limited to the embodiments, and any person skilled in the art can make any possible variations and modifications to the technical solution of the present invention by using the methods and technical matters disclosed above without departing from the spirit and scope of the present invention, so any simple modifications, equivalent variations and modifications to the embodiments described above according to the technical matters of the present invention are within the scope of the technical matters of the present invention.
What is not described in detail in the present specification belongs to the known technology of those skilled in the art.
Claims (6)
1. A system for suppressing high and low temperature constant current point drift for aerospace, comprising: the constant current source power conversion front stage, the filter inductor L10, the filter capacitor C10, the power load, the sampling resistor R31, the differential current sampling circuit, the constant current function control circuit and the PWM control chip;
the filtering inductor L10, the power load and the sampling resistor R31 are sequentially connected in series and then connected with a front stage of constant current source power conversion; one end of the filter inductor L10 is connected with the front stage of constant current source power conversion, and the other end is connected with one end of an electric load; the other end of the electric load is connected with one end of the sampling resistor R31; the other end of the sampling resistor R31 is connected with a constant current source power conversion front stage;
the filter capacitor C10 is arranged in parallel with the electric load;
two sampling ends of the differential current sampling circuit are respectively connected with two ends of the sampling resistor R31 to acquire and obtain the voltage on the sampling resistor R31, so as to realize the sampling of the output current;
the differential current sampling circuit, the constant current function control circuit and the PWM control chip are sequentially connected in series and then connected with a constant current source power conversion front stage; the output end of the differential current sampling circuit is connected with one end of the constant current function control circuit; the other end of the constant current function control circuit is connected with one end of the PWM control chip; the other end of the PWM control chip is connected with a constant current source power conversion front stage;
a differential current sampling circuit comprising: the high-speed operational amplifier N1, a power supply resistor R81, a positive phase input resistor R82, a negative phase input resistor R83, a differential amplifying resistor R73, a differential amplifying resistor R74, a power supply Vcc and a power supply filter capacitor C44; one end of the sampling resistor R31 is connected with the negative phase input resistor R83 and then connected with the negative phase input end of the high-speed operational amplifier N1, and the other end of the sampling resistor R31 is connected with the positive phase input resistor R82 and then connected with the positive phase input end of the high-speed operational amplifier N1; the differential amplifying resistor R73 is connected in parallel with the negative phase input end and the output end of the high-speed operational amplifier N1; the differential amplifying resistor R74 is connected in parallel with the non-inverting input end of the high-speed operational amplifier N1 and the SGND; the power supply Vcc is connected in series with a power supply resistor R81 and a power supply filter capacitor C44 and then connected with SGND; the g pin of the high-speed operational amplifier N1 is connected with the common end of the power supply resistor R81 and the power supply filter capacitor C44; the g pin of the high-speed operational amplifier N1 is: the chip power supply positive end;
when the positive phase input and the negative phase input of the differential current sampling circuit are the same, the differential current sampling circuit has output; adding an offset voltage to the positive phase input and the negative phase input of the differential current sampling circuit to enable the output of the differential current sampling circuit to be 0; the magnitude of the offset voltage changes along with the change of temperature, and the drift amount of the offset voltage is recorded as delta Vos;
under normal temperature, the output voltage V of the differential current sampling circuit Collecting The method comprises the following steps: v (V) Collecting =kx (i×r+vos); under the condition of normal temperature condition and constant current output, the constant current reference signal V1 is: v1=kx (i×r+vos); wherein K represents the amplification factor of the differential current sampling circuit, k= R73/R83; vos represents an offset voltage value under normal temperature conditions; i represents the value of the current flowing through the sampling resistor R31; r represents the resistance value of the sampling resistor R31; i represents a current value of a constant power supply current output by a power conversion front stage of the constant current source; at normal temperature, Δvos=0;
under the condition of temperature alternating condition and constant current output, the constant current reference signal V1 is: v1=kx (i×r+vos+Δvos); when delta Vos is positive, the output of the differential current sampling circuit is larger, so that the constant power supply current output by the power conversion front stage of the constant current source is smaller; when delta Vos is negative, the output of the differential current sampling circuit is smaller, so that the constant supply current output by the power conversion front stage of the constant current source is larger; wherein, under the condition of temperature alternation, Δvos=vos High height Or Vos Low and low Subtracting outVos，Vos High height Representing offset voltage value, vos under high temperature condition Low and low Representing offset voltage values under low temperature conditions.
2. The system for suppressing drift amount of high and low temperature constant current points for aerospace according to claim 1, wherein the constant current source power conversion front stage modulates, rectifies and converts input power and outputs supply current; the power supply current supplies power to the power utilization load through the filter inductor L10 and the filter capacitor C10; the output current of the power utilization load flows back to the power conversion front stage of the constant current source through the power output loop; the sampling resistor R31 is arranged on the power output loop and is used for representing the output current by adopting a tiny voltage signal.
3. The aerospace system of claim 2, wherein the high and low temperature constant current point drift amount is controlled by a controller,
the differential current sampling circuit amplifies and samples a micro voltage signal on the sampling resistor R31 to obtain a current sampling signal, and the current sampling signal is sent to the constant current function control circuit;
the constant current function control circuit performs proportional integration on the constant current reference signal and the current sampling signal to obtain an error amplification signal, and sends the error amplification signal to the PWM control chip;
the PWM control chip generates a pulse width control signal according to the comparison result of the error amplification signal and the internal triangular wave, and sends the pulse width control signal to the constant current source power conversion front stage, so that the constant current source power conversion front stage adjusts the output power supply current according to the pulse width control signal, and the constant power supply current is ensured to be output by the constant current source power conversion front stage according to the constant current reference signal.
4. The system for suppressing drift amount of high and low temperature constant current point for aerospace according to claim 1, wherein the filter inductance L10 is: microhenry-millihenry inductance and filter capacitor C10 is: the micro-method-milli-method capacitance and the sampling resistor R31 are as follows: milliohm-level resistance.
5. The system for inhibiting the drift amount of high and low temperature constant current points for aerospace according to claim 1, wherein the positive phase input resistor R82 and the negative phase input resistor R83 have the same resistance value and are kiloohm resistors; the resistance values of the differential amplifying resistor R73 and the differential amplifying resistor R74 are identical, and the differential amplifying resistor R73 is a resistor of the order of kilohms to hundred kilohms; the power supply Vcc is a +12V power supply; the high-speed operational amplifier N1 is powered by a power supply Vcc single power supply.
6. The aerospace system of claim 1, wherein the system is further configured to suppress the drift of the constant current point at high and low temperatures,
under normal temperature conditions, the constant current reference signal V1 is: k× (I) 1 ×R+Vos)；
Under the high/low temperature condition, the constant current reference signal V1 is: k× (I) 2 ×R+Vos+△Vos)；
When the constant current reference signal V1 is constant, the amplification factor K of the differential current sampling circuit is constant, and the resistance value R of the sampling resistor R31 is constant, there are: - Δvos=r×Δi=r× (I 2 －I 1 )；
Wherein I is 1 Represents constant current point at normal temperature, I 2 Shows constant current point at high/low temperature, and DeltaI shows drift amount of the high/low temperature constant current point.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110932466.5A CN113659804B (en) | 2021-08-13 | 2021-08-13 | System for restraining drift amount of high-low temperature constant current point for aerospace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110932466.5A CN113659804B (en) | 2021-08-13 | 2021-08-13 | System for restraining drift amount of high-low temperature constant current point for aerospace |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113659804A CN113659804A (en) | 2021-11-16 |
| CN113659804B true CN113659804B (en) | 2023-06-06 |
Family
ID=78480280
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110932466.5A Active CN113659804B (en) | 2021-08-13 | 2021-08-13 | System for restraining drift amount of high-low temperature constant current point for aerospace |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113659804B (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007318394A (en) * | 2006-05-25 | 2007-12-06 | Toyota Industries Corp | Offset voltage adjusting circuit |
| CN103731033A (en) * | 2013-12-19 | 2014-04-16 | 山东艾诺仪器有限公司 | Wide-range DC power supply with constant power output characteristic |
| CN203872056U (en) * | 2014-05-06 | 2014-10-08 | 中国电子科技集团公司第四十一研究所 | Direct-current power supply controlled by constant power |
| CN106289560A (en) * | 2016-08-01 | 2017-01-04 | 湖南省耐为数控技术有限公司 | A kind of circuit for motor temperature Precision measurement |
| CN109343638A (en) * | 2018-10-26 | 2019-02-15 | 上海新跃联汇电子科技有限公司 | A kind of High Precision Low Temperature drift bipolarity Multichannel constant-current source circuit |
| CN111864830A (en) * | 2020-06-30 | 2020-10-30 | 上海空间电源研究所 | Aerospace lithium battery constant-current constant-voltage charging control circuit |
| CN113050742B (en) * | 2021-03-11 | 2022-07-29 | 电子科技大学 | Precise constant current source circuit |
-
2021
- 2021-08-13 CN CN202110932466.5A patent/CN113659804B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113659804A (en) | 2021-11-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107839500B (en) | Lithium battery pack balance control method and system for dynamically correcting SOC | |
| CN103872915A (en) | DC (direct current)-DC converter and DC-DC converter system | |
| CN101988943A (en) | Power conversion efficiency measurement system and method thereof | |
| CN110542774A (en) | Feedback type bidirectional current magnetic isolation sampling circuit | |
| CN208506629U (en) | A kind of power supply circuit based on far-end feedback | |
| CN113659804B (en) | System for restraining drift amount of high-low temperature constant current point for aerospace | |
| CN206858674U (en) | A kind of aluminium electrolysis anode guide rod distributed current Detection ＆ Controling apparatus and system | |
| CN212905201U (en) | Automatic power consumption test circuit of electronic product | |
| Appelo et al. | The zero-flux DC current transformer a high precision bipolar wide-band measuring device | |
| CN105548725A (en) | Online detector for super capacitor and internal resistance detection method based on detector | |
| CN216774621U (en) | High-power direct-current power supply circuit | |
| CN106291065B (en) | Voltage sampling circuit | |
| CN213602560U (en) | Circuit for compensating according to load | |
| CN112953171B (en) | High-precision power supply based on direct-current resistance measurement and implementation method thereof | |
| CN105487947A (en) | Method for testing power conversion efficiency | |
| CN210015228U (en) | Automatic test detection device | |
| CN211061595U (en) | Feedback type bidirectional current magnetic isolation sampling circuit | |
| CN103134981B (en) | Power detecting method and device | |
| CN211827061U (en) | Constant current source generating module | |
| CN209280798U (en) | AC voltage sensor and its sample circuit | |
| CN105159380A (en) | Multi-channel separation constant voltage and flow source | |
| Tulsyan et al. | Maximum Power Point Tracking based Solar Charge Regulator | |
| CN205102964U (en) | Portable soft organizational interface force measuring system of multichannel | |
| US11994540B2 (en) | Current measuring system | |
| Petibon et al. | Automatic data acquisition system for testing photovoltaic conversion chains performances in real conditions |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |