JPS6051424A - Inverter controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inverter unit (device), which mainly consists of a combination of commercial lighting, etc. and an inverter unit, and when normal, the inverter unit 1 is charged and operates; This invention relates to inverter control considerations that are applied to, for example, uninterruptible power supplies, etc., which are equipped with an inverter that always performs a reverse conversion operation to supply power from the inverter expansion side to the load.

In general, uninterruptible power source equipment uses a forward converter to convert the AC current from a commercial power supply etc. into direct current, and this IK current converter to convert it into alternating current, which is then applied to the load via an AC filter. It is configured to supply power. In the event of a power outage, the commercial power source is connected to the direct current source 11, which is connected to the DC power source 11, and is supplied to the power load via the inverter. .

However, in such conventional systems, even when the commercial power supply is normal, electricity is supplied to the load via the power converter, so there is a problem in terms of efficiency. Furthermore, since a forward converter is usually built in as a DC power source, it is bulky and economically disadvantageous.

The present invention does not go beyond the above-mentioned points, and by performing parallel operation of a commercial power source, etc. and an inverter device, when the power source is normal, power is directly supplied from the power source to the load, and during this time, the inverter device performs a charging operation. By supplying power from the inverter to the load in the event of a power failure, the system improves efficiency, downsizes the converter, and improves reliability when switching power supplies, and eliminates the need for a charger and converter. downsized.

The object of the present invention is to provide an inverter control device that can improve economical efficiency.

What is the purpose of this invention? AC input from commercial power supply to achieve? A thyristor is installed on the power line that supplies the load.
AC switch such as switch? An inverter including a battery, an inverter, a matching transformer, and an AC filter, which are connected in parallel to the main circuit by connecting the output i to the load side of the AC switch. a power supply level monitoring means for detecting the state of the power supply; a power detection means for detecting active power and reactive power of the output of the inverter; When the power supply is normal, the AC switch is turned on and 1! In addition to supplying power from the source to the load,
The control means controls the frequency so that the battery charging voltage of the inverter is constant based on the active power detection value from the power and force detection means, and also controls the frequency to keep the battery charging voltage of the inverter constant based on the reactive power detection value from the power detection means. Current! So that it becomes zero′
Bore pressure control is performed, and AC switch is turned off when power is abnormal.
l.The power supply from the power supply to the load is cut off, and the control means controls the inverter imv based on a predetermined setting value, and the output of the inverter device supplies power to the load. It is configured to supply Further, according to the present invention, the control means includes a phase adjustment means such as a PLL control circuit that adjusts the phase of the power source and the inverter device, and when the phase adjustment means matches the phases of the two, the control means includes an AC When the switch is turned on, the system is configured to switch between frequency control, which keeps the battery charging voltage of the inverter device constant, and voltage control, which makes the reactive current zero.

Hereinafter, one embodiment of the present invention will be described with reference to the attached drawings lf'.

FIG. 1 is a block diagram showing one embodiment of an inverter control device according to the present invention.

10 is a power line to which AC input from a commercial power supply is supplied, 12 is a power line inserted into this 1 "source line" 0, for example, a diode and a thyristor, and 4 is a parallel circuit. This is an AC switch such as a thyris switch, which is formed by connecting cyris hooks in reverse parallel. ] 4 is an inverter device, and batch I+ 14 performs a predetermined charging operation 7 when the power supply is normal.
a, an inverter 14h that converts direct current to alternating current, a matching transformer 14c for impedance matching, and LC
It is composed of an AC filter 14d such as a circuit.

This inverter device 14il''l: its output is connected in parallel to the main circuit section by connecting it to the load side of the current transformation switch 12.16 is connected to the ship's power supply based on the detected amount from the current transformer CT1. This is a power level monitoring unit that detects the level status and determines whether the power supply is normal or abnormal.

Reference numeral 18 denotes a power detection device for detecting the active power and non-active power of the output of the inverter #14, which detects the current transformer CT, voltage transformer PT, and The active power fPl and reactive power iQIY are detected based on the amount. 20S.

is a charging current setting device composed of a variable resistor, 20S
, is a reactive current setter similarly constructed by a variable resistor. 22 is a detector/active power from 8 and a setting device 20
Matching point 24, which matches the output of day 1, is an amplifier that amplifies the deviation of this matching point 22, and 26 is a switch circuit that becomes ○N when the power level monitoring unit 16 determines that the power supply is normal. It is. Also, 28 is the phase alignment between the power supply and the inverter device 14 when the power is restored? The voltage transformer PT is a PLL (phase locked loop) circuit which acts as a phase adjustment means to perform the operation in response to the line sense voltage input through the '%' and the feedback output from the logic circuit described below. do. 30 is the power level kV viewing section 16
A switch circuit that turns on when it is determined that the power has been restored.
Is 32 the predetermined frequency setting value? A frequency setting device consisting of a variable resistor for setting, a switch circuit 2 at 34
6 or 30 and the setting output of the frequency setter 32? Adder to add, 36 is this point 34
] 0 Voltage controlled oscillator (hereinafter referred to as VC) that operates according to the deviation output
38 is a logic circuit that generates a logic output vVM corresponding to a predetermined frequency output according to the VC036f7) output. This is a triangular wave generating circuit that generates a triangular wave according to the output of the logic circuit 38 of the 40-bit filter. 42 is the current transformation detected by the voltage transformer PT? AC that converts to DC
The DC converter 44 is the reactive power +Ql detected by the detector 18 and the setting device 20B! This is the matching point where the set output and the general match are made. Also, 46 is an amplifier that amplifies the deviation output from this hole matching point 44, 4th is a switch circuit that becomes ○N when the power level monitoring unit 16 determines that the power supply is normal, and 50 is a variable resistor. Simplified output voltage setting device,
52 is A, the output of the C/DC converter 42;

This is an adder that calculates the reactive power and output of the switch circuit 48 valves and the set output from the voltage setter 50. Further, 54 is an output voltage control amplifier that amplifies the output of the adder 52, 56 is a frequency; A comparator that compares the deviation output from the matching point 56 with a predetermined value, and a gate N path for controlling the gate of the converter +4h based on the output of the comparator 558 of the 60-bar.

Is one embodiment of the present invention configured as described above? 1. When the power level monitoring unit 16 determines that the commercial power supply is normal, the monitoring unit 16 issues an ignition command to the AC switch 2 and turns it on.
As a result, 1cm contact power is supplied to the load from the commercial power source. At this time, the frequency voltage control of the inverter device 140 is as follows.
2 Do sea urchins. When the power supply is normal, the switch circuit 26 is in the O state.
N, switch circuit 30 is ○FF, switch circuit 48 is O
A command is given from the monitoring unit 16 so that the number of times N is reached. In this case, the active power detected by the detector 18 +Pl
is the set output of the setter 20S, and the output is combined at the six-point 22, the deviation output is amplified by the amplifier 24, n is added to the output of the frequency setter 32 by the adder 34, and the frequency of the inverter is a. m11 go loop 7! , becomes the input to the VCO 31'i. On the other hand, the reactive power +Ql detected by the detector 1B is matched with the setting output of the setting device 2082 at the adjustment point 44.
The difference output is amplified by g546, and the amplified output is added to the output of the AC/DC converter 42 and the output voltage setter 50 by the adder 52.

The output of this adder 52 is the voltage control loop 3 of the inverter. -pui! , the voltage controlled amplifier 540 input point.

Therefore, the output of Vc036 in frequency control loop l, is the output of logic circuit 38. The output of the voltage 1R11ml amplifier 54 in the voltage control loop l becomes the other input of the matching point 56, and each input is combined n.
, the deviation output thereof becomes the input of the comparator 58. According to this 1, the gate circuit 60 controls the gate of the inverter 14b of the inverter device 14 according to the output of the comparator 58 to determine the output voltage and output frequency. control automatically.

By forming the frequency control loop / as described above, the setting device 208 . It is possible to flow a charging current set by . In such a case, if the present invention is used, the battery will be charged when the power supply is normal. The setting value of the current setter 20B is set so that the inverter device 14 receives a certain amount of reverse current from the quotient power source, and the gate of the inverter 14h is controlled via the frequency control loop 11 to generate the batch I+ 14. Control is performed so that the charging snow pressure of a is constant.

Figure 2 shows a vector diagram for battery charging control when the commercial power supply is healthy, and in this vector diagram, vo
is the terminal lightning voltage at the load end, V8 is the commercial power supply voltage, ■
Le is the voltage of wiring inductance on the commercial power line up to the load point (if a reactor is inserted in the power line, the voltage across the reactor is shown), vl is the inverter output voltage, Vl,, i is AC Filter current +tf, pressure, Ehltl battery voltage, ■oba' output from the power supply side, Ir is the charge current, r/ is the battery charging current (effective current) taken into the inverter side, ■. 5 shows the AC filter's capacitor charging current Fd, and 1 shows the output current of the inverter. As is clear from this vector diagram, the current r that is the difference between the output current I4 on the power supply side and the load force construction
r' v Inverter through the frequency control loop 11 and voltage control loop 12 of the inverter so as to input the data into the inverter side], 4b's gate %' automatically controls the charging of the battery 14' This is to control the constant voltage to a value equal to the city pressure Eh.

Furthermore, in order to form the voltage control loop l as described above, the reactive current based on the output voltage set by the setting device 2082 can be used. In such a case, in the present invention, when the power supply is normal, the setting amount of the output voltage setter 20S2 is set to zero, and the gate y of the inverter 14i1 is controlled via 12 voltage control loops so that the reactive current becomes zero. to control.

6. The operation of the present invention which performs the predetermined control aW as described above will be described in detail based on the vector diagram of the YiZ diagram. When the power supply is normal, the frequency control loop shown in FIG.

? The output frequency of the inverter 14b is controlled through the inverter 14b so that the output frequency of the inverter 4 is slightly lower than the frequency on the power supply side. In parallel with this action,
Voltage control loop l of FIG.

? The output voltage V1%' of the inverter 14b is automatically controlled so that the reactive current of the inverter device 14 becomes zero. Therefore, when the power supply side is normal, as shown in the vector diagram in FIG.
Capacitor charge 1 [7 construction. The inverse transformer 14 is the vectorial addition of
A current 1 is generated at the output 'b, and voltage vLt between the terminals of the reactor L1 of the current transformer filter 14d and voltage V at the load end are generated by this electric construction 1. The value added vectorially becomes the output voltage v1 of the inverse converter 14b,
In addition, the voltage between the terminals of the wiring reactor up to the load end, vLe (or the voltage between the terminals of the reactor when the reactor is inserted in the power supply line), which is caused by load electrical installation,
Terminal voltage V at the load end. The voltage V on the power supply side is the sum of these vectors. And, the output current on the power supply side r/
What is subtracted from the load current 1r vector is the effective current rrl for charging 14 batteries.
Similarly, the voltage between the terminals of the power supply line wiring II ACdle is “L”
e is the charging voltage Ei8 (voltage between terminals) of batch II-14a.

The above is the operation when the power supply is normal.Next, the operation when the music power supply is abnormal will be explained. When the power supply V-pel monitoring unit 16 determines that the commercial power supply is abnormal, the gate signal of the AC switch 12 is first locked and turned off to 0FF (natural arc extinction).
At the same time, switch circuits 26 and 48 are turned off. With this nVC, the control input of the frequency control loop 110 becomes the set output of the frequency setter 32, and the control input of the voltage control loop 7t(7) becomes the set output of the output voltage setter 50 and the output of the AC/DC converter 52. Become. Therefore, depending on these frequencies and voltage amounts, the gate of the inverter 14b of the inverter device 14 generates an output tzi and a voltage corresponding to the gate. Therefore, the load is supplied with power according to the output of the inverter device 114.

In this way, even if an abnormality occurs in the commercial power supply, the power supply source will be switched from the commercial side to the inverter side without a momentary interruption.
Power can continue to be supplied to the load.

I will briefly explain what happens when commercial power is restored.

When the power level monitoring unit 16 determines that the commercial power supply has started to recover from an abnormal state, first the switch circuit 30
'%' is turned on and phase matching between the commercial power supply and the inverter device 14 is performed using the Y PLL f(t control method. In other words, the output of the PLL control circuit 28 and the setting output 11 of the frequency setter 32 - input to the adder 34 San.

The output of this adder 34 is inputted to the VC (136 logic) circuit 38.The logic circuit 38 supplies the frequency scattering chip to the triangular e generation circuit 40 according to the output of the VC036, and also supplies the frequency The chip feeds back to the PLL circuit 28 to match the voltage phase of the power supply side taken in from PT2 and the logic phase of the logic circuit 3B to a predetermined phase, and controls the phase of the inverter as the voltage phase of the power supply side advances. When it is confirmed that the phases of the commercial power supply and the inverter #14 match through this detailed PLL control, the switch circuit 30y is turned OFF by a command from the power supply level monitoring section 16.

Switch circuit 26 and 48vON. As a result, the inverter device 14 returns to the battery charging voltage! Switches between frequency control to keep it constant and voltage control to make the reactive current zero. At this time, the AC switch 12i is turned on in response to a command from the power level monitoring section 16, and power is supplied from the commercial power source to the load.

As described in detail above, the present invention has a parallel configuration with a power supply and an inverter device, and always performs frequency control 7 so that the battery voltage of the device is charged at a constant voltage, and also controls the frequency of the inverter device to charge the battery voltage at a constant voltage. 4. Perform voltage control to make the voltage zero.
Box, power from source to load? At the same time, in the event of a power failure such as a power outage, the power supply from the power source to the load is cut off and power is supplied from the inverter device. It is configured to supply to the load. Therefore, since power is always supplied from the power supply to the connected load without going through an inverter device, a comprehensive moving vehicle is preferable. In addition, depending on the capacity of the inverter, the inverter supplies power to the load only when the commercial power supply is in an abnormal state such as a power outage, and when the power supply is healthy, Batch II- is controlled at a constant voltage. A reverse converter to take in the charging current? Since only one control is required, the device can be miniaturized. That is, in reality, the inverter device only needs to have enough capacity to guarantee power supply to the load for a short period of time until the private IIL machine starts operating after a commercial power outage. Furthermore, in the event of a power failure, the directional supply source can be switched from the commercial power supply to the inverter device by simply switching the AC switch inserted in the power supply line to the load, improving reliability during this switching. Furthermore, when the power is restored, a PLL control circuit provided in the control means of the inverter device is used to match the phase between the power source and the inverter device, and when the phases match,
Since power is supplied to the load from the commercial power supply, the phase adjustment accuracy is high and the transition to constant operation is smooth.
Reliability can also be measured from this point.

Moreover, in the present invention, since the inverter device charges the battery at a constant rate when the power supply is normal, there is no need for a charger (thyristor rectifier) for charging the battery. vessel?
Since it is not necessary, it is possible to reduce the size and improve economic efficiency.

[Brief explanation of drawings]

FIG. 1 shows an example of an inverter control bag according to the present invention. The block diagram shown in FIG. 2 is a vector diagram when the battery of the inverter device shown in FIG. 1 is charged from a commercial power source. 10...Power line, 12...AC switch, 14
...Inverter device, 14a...Battery, 14b
...+iC&m, 14 C...matching transformer, 14d...AC filter, 16...power supply V bell monitoring unit, 18...power detector, 20S,...charging current setting device , 20B, “°Reactive power setter, 26, 30.
48... Switch 4 Tsuchi circuit, 28... PLL control circuit, 32... Frequency setter, 50... Output voltage general regulator. 5 13 S, Figure 7

Claims (1)

[Scope of Claims] 111 A main circuit section configured by inserting an AC switch into a power supply line that supplies an AC load from a power source such as a commercial power source, and an output terminal W of the AC switch connected to the load II of the AC switch.
A battery and an inverse conversion section are connected in parallel to the main circuit section by connecting eight batteries. What is the status of the inverter device, which consists of a series circuit of a matching transformer and AC filter, and the power supply? Power supply level monitoring means for monitoring, power detection means for detecting active power and reactive power output from the inverter device, and control means for controlling the inverter device based on the outputs of the power supply level monitoring means and the power detection means? When the power supply level monitoring means determines that the power supply is normal, the AC switch yI10N is activated to supply power from the power supply to the load, and the control means controls the power supply. Based on the active power detection value from the force detection means, the frequency is controlled so that the batch 11 charging voltage of the spear inverter device becomes constant, and the reactive current becomes zero based on the reactive power detection value from the power detection means. Voltage control #IV is performed, and
When the source level monitoring means determines that the power source is abnormal, the AC switch 9 is turned OFF to cut off the power supply from the power source to the load, and the control means controls the lock inverter based on a predetermined set value. An inverter control device characterized in that power is supplied to a load using the output of the inverter device. (2) The control means includes a phase adjustment means for adjusting the phases of the power source and the inverter device, and when the phase adjustment means matches the phases of the two, the AC switch is selected. Claim 111 characterized in that when the inverter device is turned on, the inverter device is switched to frequency control control to keep the battery charging voltage constant and voltage control to make the reactive current zero.
Inverter system #neck as described in section. (3) The inverter splitting control device according to item 11) of the patent application, wherein the AC switch is a thyristor switch. (4) The inverter control device according to claim (2), wherein the phase adjustment means includes a PLL control circuit.