RU2560720C1 - Spacecraft power supply system with optimised control for solar battery power - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: power supply system comprises solar battery (SB), accumulator battery (AB), voltage regulator and discharge device made as bridge inverters. Charge device, two separate matching transformers, control system with optimised power control, load with different feed voltage rates. SB is connected to voltage regulator, which output is connected to primary winding of the first transformer. AB is connected to discharge device, which output is connected to the first winding of the second transformer and to charge device, which input is connected to secondary winding of the first transformer. Secondary windings of the first and second transformers are coupled in series and feed the load through rectifier.

EFFECT: improved energy efficiency due to implemented optimised power control both in AB charge mode and in the mode of on-board load joint power supply from SB and AB.

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Description

The invention relates to the field of converting technology, in particular to onboard power supply systems (BOT) of spacecraft (SC), and can be used in the design and construction of power systems for automatic spacecraft based on solar and storage batteries (SB and AB).

The technical result of the invention is to increase the energy efficiency of the spacecraft’s power supply system through the implementation of extreme power control (ERM) of solar batteries both in the battery charge mode and in the mode of joint supply of onboard load from the SB and AB.

A widely known power supply system [1] with extreme power control of a photovoltaic battery, comprising a photovoltaic and storage batteries, a series voltage regulator (LV) for supplying a load from a photovoltaic battery, a charging and discharge device (charger and switchgear). Extreme regulation of the power of the photovoltaic battery is carried out by the charger when the load is powered and the battery is simultaneously charged, as well as by a voltage regulator while the load is powered from the SB and AB. The power supply system with a photoelectric battery is designed to form one power low-voltage (27-28 V) load power bus. For the formation of other ratings of the supply voltage, the development of additional converters is necessary, which in turn increases the development time of the BOTS of the spacecraft and the spacecraft as a whole.

The disadvantage of this power supply system is that when creating high-voltage SEP spacecraft (100 V), the maximum value of the open circuit voltage of the SB at the moments of exit from the shadow areas of the Earth exceeds 200 V, which is unacceptable due to the possibility of electrostatic discharges between the photodiode chains under vacuum conditions Sat or current collection elements. To limit the voltage on the SB requires the use of special devices or the implementation of the operation modes of the BOT, limiting the increase in voltage on the cooled SB.

Currently, the design of high-voltage high-voltage Russian and foreign BOTs is carried out on the basis of SB shunt voltage regulators [2], which limit the voltage on the SB at the voltage level of the load power bus and therefore do not allow implementing the SBE mode.

Closest to the technical nature of the claimed invention is the power supply system of the spacecraft described in the patent [3] (figure 1).

The power supply system consists of a solar battery 1, a battery 2, a voltage stabilizer for a solar battery 3, a discharge device for a battery 4, a battery charger 5, an extreme power regulator for a solar battery 6, a current sensor for a solar battery 7, a transformer 8, and primary transformer 9 windings , 10, secondary windings of the transformer 11, 12, 15, 20, power devices 13, 16, 18 loads of direct or alternating current 14, 17, 19, control circuits 21 transistors 22-25 voltage stabilizer 3, control circuits 26 transistors 27-30 bit device 4.

The power supply system operates as follows.

When the power of SB 1 exceeds the total power consumed by loads 14, 17, 19 (power supply of loads from SB) by voltage stabilizer 3, a stable voltage is maintained using the feedback of device 18 on the secondary winding 20 of transformer 8. On the secondary windings 11, 12, 15 of the transformer 8, a stable voltage is also maintained taking into account the transformation ratios of the windings. At the same time, AB 2 is charged, memory 5, RU 4 and SB 6 are shut off.

When the battery is charged, the charger 5 is turned on. The signal on the inclusion of the charger 5 is fed to the input of the ERM 6. As a result, the ERM mode of SB 1 is realized. At the same time, the RU 4 is disabled.

When the load is supplied from the battery and the power of SB1 is equal to zero, the switchgear 4 is connected, the voltage is stabilized at the secondary winding 20 of the transformer 8 using the feedback of the device 18. In this case, the voltage stabilizer 3, EPM 6, memory 5 are disconnected.

When the load is supplied together from the SB and AB, the voltage on the secondary winding 20 of the transformer 8 is stabilized by the RU 4, which compensates for the lack of power generated by the SB. The voltage on the SB is determined by the voltage level of the battery, since the SB and the battery in this mode are connected in parallel through the transformer, this eliminates the possibility of regulating the voltage on the SB and, accordingly, the implementation of the extreme power control mode of the SB. The power generated by the power supply will be determined in this case by the voltage of the power supply brought to the power supply through the transformation ratio specified during design.

Thus, the power supply system [3] cannot carry out the extreme power control mode of the power supply in the mode of joint power supply of the load from the power supply and the power supply, which is its main drawback.

The aim of the invention is to increase the energy efficiency of the SEP KA through the implementation of extreme power control SB both in charge mode of the battery and discharge of the battery (while supplying the load from the SB and AB).

Figure 2 presents a functional diagram of the inventive power system of the spacecraft with extreme power control SB, which contains a solar battery 1, a battery 2, a voltage regulator 3, made in the form of a bridge inverter on transistors 11-14, a discharge device 4, made in the form bridge inverter transistors 15-18, charger 5, transformer 6 with primary winding 20 and secondary windings 21-23 _{1 ... n} , transformer 7 with primary winding 25 and secondary windings 24, 26 _{1 ... n} , rectified Iteli 8 _{1 ... n} , a control system (SU) with an ERM 9, a device for monitoring the degree of charge (UKZB) AB 10, a current sensor 19, load 27 _{1 ... n} .

The solar battery 1 is connected to a voltage regulator 3, the output of which is connected to the primary winding 20 of the transformer 6. The battery 2 is connected to a discharge device 4, the output of which is connected to the primary winding 25 of the transformer 7. In addition, the battery 2 is connected to the charger 5, input which is connected to the secondary winding 22 of the transformer 6.

The secondary windings 23 _{1 of the} transformer 6 and 26 _{1 of the} transformer 7 are connected in series to a common circuit that forms the total voltage, which, after rectification by the rectifier 8 _1, supplies the load 27 ₁ . Such a connection of the secondary windings makes it possible to regulate the voltage at SB 1, which means that the ERM mode is realized in the discharge mode AB 2, i.e. while supplying the load 27 ₁ from SB 1 and AB 2. Similarly, other power supply channels of the loads 27 _{2 ... n are formed} .

The formation of the output rectangular voltages of the inverter PH 3 occurs due to the alternate unlocking of the transistors forming the diagonals of the inverter, while the transistors of the inverter racks are unlocked alternately with an interconnect pause, which eliminates shorting of the power source. The regulation of the summed output voltages of the voltage regulator 3 and the discharge device 4 is provided by phase shifting the control pulses of the transistors of one rack of the bridge inverter relative to the other, as a result of which pulse-width regulation of the inverter voltage is realized. So, for example, the regulation of the output voltage of the PH 3 is carried out by a phase shift of the control pulses of the transistors 11, 12, which are unlocked alternately, relative to the control pulses of the transistors 13, 14, which are also unlocked in turn by a certain angle α _PH , which determines the pulse width of the output voltage γ _SB by the expression:

In the extreme case, at a shear angle of α _PH = π, the transistors 11, 13 turn on in phase on one half cycle and 12, 14 on the other, which leads to the shortening of the primary winding 20 of transformer 6 by inverter transistors, with γ _PH = 0. Similarly, the regulation of the output voltage RU 4.

The control pulses are generated by the control system 9, to which the current sensor 19, the measuring winding 21 of the transformer 6 (voltage sensor) and the measuring winding 24 (voltage sensor) of the transformer 7 are connected. The sensors are designed to calculate the power received from SB 1, the location of the sensors in alternating circuits current allows you to implement them on the basis of measuring windings, which reduces the cost of the product.

The power supply system of the spacecraft operates in the following modes.

1. The load power is less than the power generated by the SB (P _N <P _SBmax ), the _battery is charged.

When battery 2 is charged, charger 5 is disconnected. The inverter of the voltage regulator of the solar battery 3 stabilizes the voltage at the loads 27 _{1 ... n} using the control system 9 by the feedback signal from the measuring secondary winding 21 of the transformer 6. Considering that at Р _Н <Р _Сmax it is not necessary to discharge the battery 2, the load voltage is 27 _{1 ... n is} entirely determined by the inverter PH 3. The voltage of SB 1 exceeds the optimal value by the I – V characteristic (U _SB > U _SBmax ) and is determined by the current power balance in the system P _N ≈ P _SB .

2. The load power is less than the power generated by the SB (P _N <P _SBmax ), the _{battery is} discharged.

When receiving a signal of the charge UKZB 10 AB 2 need switched charger 5 which works in the extreme power control mode Sa, consuming PH 3 with additional _memory capacity P = P _H -P _SBmah through the secondary winding 22 of the transformer 6. The voltage regulator 3 at This still works in the mode of stabilization of the output voltage, fulfilling the disturbances caused by the displacement of the operating point B AX of the solar battery. SB 1 in this case is fully used in terms of power, which is spent on supplying loads 27 _{1 ... n} and battery charge 2.

3. The load power is greater than the power generated by the SB (P _N <P _SBmax ), discharge AB. Power supply from SB and AB.

When the load power increases P _H > P _{SB ERM, the} charge of AB 2 stops, the charger 5 turns off. The inverter RN 3 in this mode cannot stabilize the output voltage and switches to the extreme power control mode (U _SB = U _{SB max} ) by the signal SU 9 using the signals of the current sensor 19 and the measuring winding 21 (voltage sensor) of the transformer 6. The output power is not enough loads on January _{27 ... n} compensated inverter discharge device 4 which carries out the necessary voltage in summing circuit additive stabilizing the output voltage measured by the secondary windings 21 of transformer 6 and 24 of the transformer 7. a diagram the operation in this mode are shown in Figure 3. Where U ₁ - voltage on the SB 1, U ₂ - strain AB 2, U ₃ - voltage regulator voltage 3, U ₄ - voltage discharge unit 4, U _OUT - output voltage to the load ₂₇ January _{... n,} α _PH - shift angle control pulses of the transistors of the voltage regulator 3, α _RU - the angle of shift of the control pulses of the transistors of the discharge device 4.

4. The solar battery does not generate power (P _SB = 0), battery discharge.

In the absence of power coming from SB 1 (R _SB = 0), the loads 27 _{1 ... n are} supplied from AB 2. The inverter RU 4 stabilizes the output voltage through the control system 9 by a feedback signal from the secondary winding 24 of transformer 7, realizing a pulse-width regulation.

Thus, in the claimed invention, the SB voltage can be regulated in a wide range, including the CVC point of the SB with maximum power, both in the battery charge mode and in the power mode from the SB and the battery, which increases the energy efficiency of the spacecraft. In addition, due to the application of the principle of summing the voltage of the sources, the claimed SEC KA has the ability to connect several batteries, with a relatively simple implementation of the equalization of their voltages.

Information sources

1. Pat. RF №2101831, H02J 7/35. Power supply system with extreme power regulation of a photovoltaic battery / K.G. Gordeev, S.P. Cherdantsev, Yu.A. Shinyakov. Application No. 95119971 dated 11/27/1995. Publ. 01/10/1998, Bull. No. 1.

2. Power supply systems for large platforms in geostationary orbit / V.V. Khartov, G.D. Evenov, B.C. Kudryashov, M.V. Lukyanenko // Electronic and Electromechanical Systems and Devices: Sat. scientific tr - Novosibirsk: Nauka, 2007. - S.7-16.

3. Pat. RF №2396666, H02J 7/34. Spacecraft power supply system / Kudryashov BC, Elman V.O., Nesterishin M.V., Gordeev K.G., Gladushenko V.N., Khartov V.V., Kochura S.G., Soldatenko V.G., Melnikov N.V., Kozlov R.V. Application No. 2009124704 dated 06/29/2009. Publ. 08/10/2010, Bull. Number 24.

Claims (1)

The power supply system of the spacecraft, consisting of a solar battery connected by its plus and minus buses to the voltage regulator built according to the inverter bridge circuit, a battery connected by its plus and minus buses to the inputs of the discharge device constructed by the inverter bridge circuit and the outputs of the charger characterized in that the voltage regulator and the discharge device are connected to different matching transformers, the output of the voltage regulator is connected to the primary the winding of the first transformer, in the circuit of which a current sensor is connected, the output of the discharge device is connected to the primary winding of the second transformer, the input of the charger is connected to the secondary winding of the first transformer, the battery charge control device is connected by its inputs to the information outputs of the battery, the control system is extreme by regulating the power of the solar battery, it is connected by its inputs to a current sensor, a measuring winding of the first transformer Ora, by measuring the winding of the second transformer and the control output of the device for monitoring the degree of charge of the battery, and the outputs with the input of the charger and with the control inputs of the transistors of the inverters of the solar voltage regulator and the discharge device of the battery, while the secondary windings of the first and second transformers are connected in series and connected to loads through output rectifiers.

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