KR100289804B1 - Power control simulator for artificial satellite - Google Patents

Abstract

PURPOSE: A power control simulator for an artificial satellite is provided to test the performance of a power controller for an artificial satellite regardless of the capacity of power. CONSTITUTION: A control and telemetry circuit processes a remote command and telemetry via a computer and an interface. A solar cell simulator module(201) realizes the characteristics of a real solar cell by realizing the characteristics of a solar cell needed by a user. A bus voltage controller(202) compares the input power level with a load-desired power level and supplies the power of needed level to a load and shunts the residual power via a switch of a controller. A battery charge and discharge device(203) performs charging and discharging by using a bidirectional converter. An AC power supply supplies DC power to each module of the solar cell simulator.

Description

Power control simulator for artificial satellite

The present invention relates to a satellite power control simulator for testing the performance of the satellite power control device regardless of the change in power capacity on the ground.

Satellites cannot be maintained and supplemented once they are in space, so they need to carry out many designs and experiments on the ground to raise the perfect satellite.

Existing simulators made in response to these requirements are designed and manufactured according to the capacity of a specific system according to the purpose of the satellite, so that only the satellites of a specific system can be tested, and a new simulator can be tested when designing a new satellite. Because of the design, a lot of cost is added to the ground test of the satellite.

In particular, as the power capacity of satellites is gradually increasing, a change in the power control method is required, but in the US, the satellite power control simulator used by NASA and some companies can test only the limited capacity set by the manufacturer, HEWLETT PACKARD Using the device manufactured in, it was not possible to actively test the power capacity increase of the satellite, but there was a problem that the cost of the test was greatly increased.

In addition, the conventional simulator described above requires a solar cell simulator as many as the number of switches in order to test a bus voltage regulator having a switching method, which consumes an additional cost.

In addition, the non-dissipative switching shunt regulator that controls the bus voltage when supplying the power generated from the solar cell uses an analog switching method and an analog PWM method, but the above-described method uses satellite power. It was difficult to solve the heat and volume increase problem that occurs at the switch during capacity increase.

The present invention solves the problem that occurs during switching by using a pulse width modulation to determine the output from the microprocessor when supplying the power generated from the solar cell to the bus, such a method first in the load The required power is detected and this value is compared with the reference value of the input power to the microprocessor.

When excessive power is generated or insufficient power is generated, the microprocessor's comparison value is used to shorten unnecessary modules of the solar array when excessive power is generated and open the module when insufficient power is generated to control the bus voltage of the satellite. .

In addition, when the power capacity required in the load exists between the capacity of each module of the solar cell array, the switch of the corresponding module switches as much as the ratio of duty required by the load.

The battery charger / discharger uses a bi-directional converter that can perform the functions of a charger and a discharger in a single converter. This method has already been commercialized on the ground and used in various industrial fields. .

Control and telemetry processing of the power controller test model is accomplished by a one-chip microprocessor.

Then, the simulator of the present invention is composed of several modules in one simulator, each module can be used separately, there is an advantage that can be simple configuration and can reduce the cost.

In addition, the bus voltage of the satellite is set differently according to the capacity and orbit of the satellite (usually + 14V, + 28V, + 35V, + 70V, etc.). And it is possible to simply change the software in the hardware produced in the present invention without the need to re-manufacturing the test device for the satellite capacity.

1 is an overall system configuration of the present invention

2 is a schematic diagram of a subsystem module of the present invention.

3 is a system control and telemetry block diagram of the present invention.

4 is a circuit diagram of a solar cell simulator of the present invention.

5 is a circuit diagram of a satellite bus voltage regulator of the present invention;

Figure 6 is a satellite battery charger / discharge circuit diagram of the present invention

[Explanation of symbols on the main parts of the drawings]

10: power control device enclosure

11: Rear part of control and telemetry circuit manufacturing module

12: Battery charger / discharger manufacturing module rear part

13: rear part of the bus module

14: solar cell simulator manufacturing module back

15: AC power supply manufacturing module rear part

17: External connection terminal with battery

18: DC70V input / output terminal

19, 26: AC220V input terminal

20: Bus voltage regulator output terminal

21: Bus voltage regulator output terminal (charger and load)

22, 27: AC220V output terminal

23: solar battery simulator output terminal

24: power ground

25: DC100V input terminal

30: computer

31: Front part of control and telemetry circuit manufacturing module

32: Battery charger / discharger manufacturing module front part

33: front side of the module for manufacturing bus voltage regulator

34: front part of solar cell simulator manufacturing module

35: AC power supply manufacturing module front part

36: solar cell simulator module configuration

37: Satellite bus voltage regulator module configuration

38: Battery charger / discharger module configuration

39: load

40: interface board

41: microprocessor main controller

42: remote command and telemetry processing device

43: battery 44: communication port

45 microprocessor 46 latch

47: EPROM 48: RAM

49: buffer and line driver 50: comparator

51: D / A converter 52, 53, 54: bidirectional buffer

401: solar cell simulator module 1 402: analog mux1

403: solar cell simulator module 12 404: current sensor 1

405: A / D converter 406: D / A converter

407, 408, 409, 410, 411: OP Amp

501: satellite bus voltage regulator module 1

502: satellite bus voltage regulator module 12

503: relay 504, 505: OP Amp

506: switch drive control circuit 507, 508: analog mux

601: satellite battery charger / discharger module 1

602: satellite battery charger / discharge module 12

603: analog Mux2604: switch drive circuit

605: current sensor 2 606: relay

607: Battery charging / discharging switch control circuit

608, 609: OP AmpBVM: Bus Voltage Monitor

LCM: Load Current Monitor BAVM: Battery Voltage Monitor

BCM: Battery Current Monitor AIVM: AC Input Voltage Monitor

DOVM: DC Output Voltage Monitor

DOCM: DC Output Current Monitor

DB: Data Bus

SASA: Solar Array Simulator Address

RCL: Regulator Command Line

BCDCL: Battery Charge / Discharge Command Line

SASCL: Solar Array Simulator Command Line

SASVFS: Solar Array Simulator Voltage Feedback Signal

BCCS: Battery Charge Command Signal

C1-9: Connector 1-9

PGND: Power Ground

VCS: Voltage Command Signal

SAO 1-12: Solar Array Output 1-12

CFS1: Current Feedback Signal1

VOS 1 ~ 12: Voltage Output Signal

VO 1-12: Voltage Output 1-12

VCS: Voltage Command Signal

SIMVS: Simulator Voltage Signal

SARSCS 1-12: Solar Array Regulator Switch Current Signal 1-12

FGOS1: Fet Gate On Signal 1

BV: Bus Voltage BG: Bus Ground

CLR: ClearOC: Over Current

REGFS: Regulator Feedback Signal GONS 1: Gate On Signal 1

RYONS 1: Relay On Signal 1 BL: Bus Line

CFS1-6: Current Feedback Signal 1-6

UPS: Up SignalLOWS: Low Signal

CC: Current Command CFS: Current Feedback Signal

CHGS: Charge Signal DSCHGS: Discharge Signal

BPL: Battery Power Line BGL: Battery Ground Line

CDFS: Charge / Discharge Feedback Signal

1 is a schematic diagram of the overall hardware structure of the present invention, and shows the front and rear parts of the satellite power control device 10 in a general rack size.

Nine connector terminals C1-C9 are formed on the rear portion 11 of the control and telemetry circuit module placed on the top.

Each of the connector terminals C1-C9 is for the interface between the modules installed below and the computer 30. The reason for forming the interface circuit with the computer 30 is for processing remote commands and telemetry.

In addition, a front panel 31 of this module is equipped with a monitor (BVM) LCM indicating bus voltage and load current.

The battery charger / discharger module is placed for the second time, and the rear part 12 of the module has a battery connection terminal 17 for connecting the battery to the outside and can be used by connecting the bus voltage of 70V generated from the bus voltage regulator. There is a connecting terminal 18.

In addition, there is a fan to prevent heat generation of the system, and this fan is placed on the front part 32 of the battery charger / discharger module. The power supplied to this is commercially available AC 220V, and the power connector (19) is used to charge the battery. It is located at the bottom right of the discharger module.

The front part 32 of the battery charger / discharger module is also equipped with an LCD instrument panel (BAVM) (BCM) which shows the voltage and current of the battery and a lamp which shows the status of the battery module.

The satellite bus voltage regulator module is located in the third, and the rear part (13) of the module has a connection terminal (21) for connecting to the battery charger / discharger and the load, and also consists of 12 for connecting the solar cell power input to the simulator. The connection terminal 20 is located at the lower left and the lower right is provided with a power terminal 22 supplied to the existing fan to prevent heat generation of the system.

The front part 33 of this module has twelve indicator lamps to indicate the status of each of the twelve satellite bus voltage regulators.

Fourth, there is a solar cell simulator module.

On the rear part 14 of the solar cell simulator module, there is a connection terminal 23 for supplying the simulated solar cell power generated in this module to the bus voltage regulator and the outside.

In addition, the power ground terminal 24 is located next to the + DC100V input terminal 25 for supplying the DC power of the solar cell simulator is also present at the bottom and the external connection for supplying AC220V at the bottom right, like the bus voltage regulator. There is a terminal 26.

Finally, the bottom module is a DC power supply module.

The function of this module is to supply DC power to solar simulator after converting it into DC power by using AC220V commercial input power.

The rear side 15 of this module has a + DC100V output terminal 28, an AC220V input terminal 29, and an AC220V output terminal 27.

In addition, an LCD instrument panel (AIVM) (DOVM) (DOCM) is installed on the front part 35 of the power supply module so that the AC input power, DC output voltage, and DC output current can be always monitored.

FIG. 2 is a subsystem diagram of the present invention and includes a solar cell simulator module 201, a satellite bus voltage regulator 202, a battery charger / discharger 203, and a microprocessor controller 206.

The solar cell simulator module 201 composed of 12 modules is configured to use each module separately, and the main feature is that the module can be added according to the load 204 capacity change. The circuit diagram is shown in detail in FIG.

The satellite bus voltage regulator 202 is composed of twelve modules as a regulator using a PWM switching method that adjusts a pulse width by determining an output in a microprocessor.

A circuit diagram of each module constituting the bus voltage regulator 202 is shown in FIG. 4. Like the solar cell simulator module 201, the bus voltage regulator 202 module can be added as the capacity increases or decreases. It can be characterized.

The battery charger / discharger (203) module is composed of six and is designed to charge and discharge the battery 208 in one converter using a bidirectional converter and is directly connected to the battery 208.

The design circuit diagram of the battery charger 203 is shown in FIG.

The remote command of the power control device and the telemetry signal 207 generated in each module are processed by the microprocessor controller 206 and each module sends and receives a signal through the interface board 205.

3 is a system control and telemetry block diagram of the present invention, upon initial operation, the microprocessor 302 is initialized via a latch 303, an EPROM 304, and a RAM 305, and then ready for startup.

First, the remote command data for controlling each submodule is sent through the bidirectional buffers 309, 310, and 311 connected to the data bus line based on the signal generated from each submodule.

The bidirectional buffers 309, 310 and 311 are connected corresponding to each submodule.

Therefore, the data sent to the bus voltage regulator 202 is sent to the remote command data to the sub-module of the bus voltage regulator 202 through the bidirectional buffer 309, the battery charger / discharger 203 and the solar cell simulator 201 Similarly, the remote command data is transmitted through the bidirectional buffers 310 and 311.

The output of each module controlled by the remote command is again fed back to the main controller 206 by the telemetry circuit.

In addition, the remote command is made by passing the command value from the computer 30 to the microprocessor 302 through the communication port 301.

For example, in order to control the charging current of the battery, the current ratio of C / 10 or C / 20 is sent from the computer 30 to the microprocessor 302 through the communication port 301, and the micro The processor 302 sends this value to the D / A converter 308, and after the battery charge current ratio is determined through the comparator 307, a signal is transmitted to the switch control circuit of the battery charger / discharger 203.

4 is a circuit diagram of a solar cell simulator of the present invention.

This circuit diagram is a simulator circuit diagram designed to simulate a solar cell power source. The circuit diagram is composed of 12 modules, from Module 1 (401) to Module 12 (403).

Each module can be used separately, and the module is configured so that several can be used in parallel.

I-V characteristic of solar cell power is to input data according to various temperature and environment inside ROM so that I-V characteristic can be selected and it can be controlled by remote command.

This commanded value is implemented in hardware by transistors Q1 through Q7 and the base signal of this transistor is passed by a remote command from the microprocessor 302.

The transmitted remote signal is transmitted through the A / D converter 405, the D / A converter 406, and the comparators 407, 408, and 409.

In addition, the output value of each simulator is transmitted to the analog mux 402.

The signal detected through the current sensor 404 is transmitted back to the comparator 408.

5 is a circuit diagram of module 1 (501) to module 12 (502) as the satellite bus voltage regulator of the present invention.

In module 1, the switch control of the bus voltage regulator is accomplished by a microprocessor command, which always compares the load with the input power.

At this time, the difference between the input power and the amount of power required by the load is shunted through this shunt switch. When the shunt exceeds the amount of power that can be controlled by each module, the shunt switch is always on.

And if the capacity of the switch among the 12 switches is required up to the capacity of the 7th module, it is the main feature of the circuit that the corresponding module is controlled on / off by PWM (pulse width control method).

Looking at the characteristics of the control circuit, when the command signal is transmitted from the microprocessor, the switch is controlled by the control circuit 506. At this time, a resistor is connected to the lower end of the switch to detect an electric current flowing through the switch to prevent the occurrence of overcurrent. Always check through 504 and 505.

When the overcurrent occurs, the relay 503 is cut off by the control circuit.

Another feature is that when the circuit is cut off, power is not supplied to the load through the circuit, thus protecting the circuit.

The voltage signal is fed back to the telemetry circuit to always check the normal operation of the circuit.

6 is a satellite battery charger / discharger of the present invention, which is composed of Module 1 (601) to Module 6 (602).

First, when the battery charge current ratio is commanded through the remote command, the command value and the output value detected at the output terminal of the converter are compared through the comparator 609.

This value is compared with the triangular wave generating circuit 610 again to adjust the pulse width and is applied to the switch control circuit 607.

The switch control circuit is controlled by a remote command for determining battery charge and battery discharge, and this value is transmitted to the switch drive circuit 604.

When the battery is charged, it operates as a battery charger by switching on / off Q9 and operating as a battery discharger by switching on / off the Q10 when discharging.

Therefore, this circuit features charging and discharging using two switches in one converter.

During battery charging and discharging, the current value flowing through the battery is obtained through the current sensor 605, and this value is collected in the analog mux 603 and then transferred back to the main control circuit.

In addition, a fuse 606 is installed at the battery input terminal to prevent excessive current from being transmitted to the battery and seriously damaging the battery.

The present invention can be utilized as a simulator for solar cell power characteristic test, power control test, remote command test and simulation in connection with other sub-systems in research institutes (including industrial companies and universities) researching satellite power control devices in Korea. There is this.

At present, there are not enough hardware devices for the simulation of satellite power control in Korea, and it is possible to replace all the partial test equipments such as solar cell simulators made by advanced countries such as the US, and to adopt the advanced method with switching method. By inventing the control circuit of the present invention, it can be applied to satellite design and fabrication in the future, and it can be provided as a test apparatus for simulation tests conducted on the ground.

Claims (4)

In the power control unit of the satellite, each module is connected to each other and the control and telemetry circuit for processing remote commands and telemetry through the computer and interface, Solar cell simulator that implements I-V characteristics of solar cell that user needs in PC by software and sends it to hardware through remote command using this value, and realizes similar characteristics to actual solar cell in hardware. A bus voltage regulator that compares the input power generated by the solar cell with the load demand and supplies only the required power from the load to the load, and surplus power is shunted through the switch of the regulator Battery charging and discharging using a bi-directional converter to charge and discharge the battery as a single converter and to change the battery charging current ratio according to the capacity of the battery, A power control simulator for a satellite comprising a method comprising an AC power supply for supplying DC power to each module of a solar cell simulator using AC as an input. The method of claim 1, wherein the control and telemetry circuit is designed to control the charging rate of the battery through the remote command from the computer and how the telemetry value is displayed on the computer to confirm the abnormal state and normal operation of the system. Power control simulator for satellites. In claim 1, the solar cell simulator is configured in a module unit and the output of each module can change the output capacity by changing the I-V characteristics in the PC, Select each module or connect several modules in parallel according to the user's required capacity. A power control simulator for a satellite that can be protected against peak current generation during switchover operation of the voltage regulator when tested in conjunction with a bus voltage regulator having a switching scheme. In claim 1, the bus voltage regulator is configured in the form of a module having a switching method to prevent excessive heat generation in each switch module, Power control simulator for satellites that performs switching control using switching PWM method.