JPH08172729A - Method of controlling self-excited rectification apparatus for charging - Google Patents

Abstract

PURPOSE: To obtain a control method which is started smoothly by suppressing regenerative power from a storage-battery installation which is generated at a time when a self-excited rectification apparatus for charging is started. CONSTITUTION: A starting signal for a self-excited rectification apparatus for charging is inputted to a one-shot circuit 21, and one-shot pulses are outputted for a prescribed time. The output value of a DC voltage detector 22 which detects a terminal voltage for a storage-battery installation is compared, by a comparator 24, with an average voltage value via a transformer 11 and a rectifying circuit 23 for an AC power supply 1. When the output value of the DC voltage detector 22 is larger than the average voltage value and while the one-shot pulses are being outputted, a DC-voltage instruction value Vc is set at zero by a limiting circuit 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of controlling a self-exciting rectifier for charging, which supplies a charging voltage and a charging current from an AC power source to a storage battery facility in which a plurality of storage batteries are connected in series.

[0002]

2. Description of the Related Art FIG. 3 shows a main circuit diagram of a self-exciting rectifier for charging of this kind. 1 is a three-phase AC power source such as a commercial power source and diesel power generation equipment, 2 is an AC reactor, 3 is a self-powered source. 3 consisting of arc-extinguishing device and diode
The phase self-exciting rectifier circuit 4 is a storage battery facility in which a plurality of storage batteries are connected in series.

The operation of the self-excited rectifier circuit 3 shown in FIG. 3 is described in detail in "Semiconductor Power Converter Circuit" (Ohm Co., Ltd.) published by The Institute of Electrical Engineers of Japan, so its explanation is omitted here. The purpose of using the self-exciting rectifier circuit 3 to charge the storage battery equipment 4 is to reduce the contained harmonic current of the AC power source 1 as much as possible and to make the fundamental wave power factor high. Performs conversion operation by PWM control.

FIG. 4 is a control circuit configuration diagram showing a conventional control method for a self-exciting rectifier for charging, and the main circuit configuration shown in FIG. 3 is shown in a simplified form in this figure. 4, in a normal state in which the charging self-exciting rectifier is in operation, the DC voltage command value Vc and the voltage of the AC power supply 1 which are the outputs of the voltage control loop for controlling the output DC voltage of the self-exciting rectifier circuit 3 (not shown). The output of the transformer 11 for detecting the current is multiplied by the multiplier 12 to obtain a current setting value, and the deviation between the current setting value and the current detection value which is the output of the current transformer 13 for detecting the current from the AC power supply 1. Is calculated by the operational amplifier 14, the output of the transformer 11 is added to this deviation by the adder 15 to form a reference wave for PWM control, and the reference wave and the carrier wave 16 are subjected to PWM control calculation by the comparator 17. PWM
The output pulse resulting from the control operation is generated by the pulse distributor 18 to generate a gate signal for each self-extinguishing type device of the self-excited rectifier circuit 3 so as to supply a desired charging voltage and charging current to the storage battery equipment 4. ing.

The terminal voltage of the storage battery equipment 4 ranges from the discharge end voltage (100% voltage) to the charge end voltage (generally 1
The voltage changes in a wide voltage range up to about 50%), and the charging self-exciting rectifier needs to start and operate over the wide voltage range. Therefore, when the self-exciting rectifier for charging is started in the state of a low terminal voltage near the discharge end voltage, the self-exciting rectifier circuit 3 cannot output the same output voltage as the voltage of the AC power supply 1 at this terminal voltage. In order to prevent damage to the self-excited rectifier circuit 3 due to excessive current flowing and to smoothly start the self-excited rectifier for charging, the above-mentioned DC voltage command value V
c is held at a slightly negative voltage, that is, the operation of the self-exciting rectifier circuit 3 is set to the regenerative mode, and the DC self-exciting rectifier for charging is started by this DC voltage command value Vc.

[0006]

According to the above-described conventional method for controlling the self-exciting rectifier for charging, for example, an instantaneous power failure occurs in the AC power source, and the operation of the self-exciting rectifier for charging is stopped during this momentary power failure period. However, when the terminal voltage of the storage battery equipment is close to the above-mentioned charge end voltage as when starting the charging self-exciting rectifier again when the AC power is restored, the self-exciting rectifier circuit at this terminal voltage is Since an output voltage equal to or higher than the voltage of the AC power supply can be output, the operation of regenerating the energy of the storage battery equipment to the AC power supply is performed in the above-described regenerative mode operation at startup.

Due to the regenerative operation of the charging self-exciting rectifier at startup in the above-mentioned state, when a diesel power generation facility or the like is used as an AC power source and the other load of this diesel power generation facility is light, There was a problem that the generator of the diesel power generation facility fell into overspeed. An object of the present invention is to provide a control method of a self-exciting charging rectifier that solves the above problems.

[0008]

According to a first aspect of the present invention, there is provided a method of controlling a self-exciting rectifier for charging, which supplies a charging voltage and a charging current to a storage battery facility in which a plurality of storage batteries are connected in series from an AC power source. If the terminal voltage of the equipment and the average voltage of the AC power supply are compared, and the terminal voltage is higher than the average voltage and within a predetermined time from the start of the charging self-exciting rectifier, the charging self-exciting rectifier The DC voltage command value is limited to a predetermined limit value, and in the second invention, the voltage of the AC power supply is divided by the terminal voltage of the storage battery equipment to obtain an input voltage waveform, and the input voltage waveform is charged. The deviation between the current setting value of the self-excited rectifier and the detected current value is added to obtain a reference wave for PWM control of the self-excited rectifier for charging.

[0009]

According to the first aspect of the present invention, the terminal voltage of the storage battery equipment is compared with the average voltage of the AC power source, the terminal voltage is higher than the average voltage, and a predetermined value is obtained from the start of the self-exciting rectifier for charging. If within the time, by limiting the DC voltage command value of the charging self-exciting rectifier to a predetermined limit value,
When the charging self-exciting rectifier is started, the regenerative power can be suppressed when the terminal voltage of the storage battery equipment is near the end-of-charge voltage.

According to the second invention, the voltage of the AC power supply is divided by the terminal voltage of the storage battery equipment to obtain an input voltage waveform, and the input voltage waveform is set to the current set value and current of the self-exciting rectifier for charging. By adding the deviation from the detected value and using it as the reference wave for the PWM control of the self-exciting rectifier for charging, the PWM control is always performed in accordance with the terminal voltage of the storage battery equipment.
When the charging self-exciting rectifier is started, regenerative power regenerated from the storage battery facility to the AC power source via the charging self-exciting rectifier can be suppressed.

[0011]

EXAMPLES In the examples of the present invention described below,
Components having the same functions as those of the conventional example shown in FIGS. 3 and 4 are denoted by the same reference numerals and the description thereof will be omitted. 1 is a control circuit configuration diagram of a charging self-exciting rectifier according to a first embodiment of the present invention.

In FIG. 1, a starting signal is input to the one-shot circuit 21 when the self-exciting rectifying device for charging is started, and for example, a one-shot pulse is output for a few seconds for the voltage control loop to rise to output a one-shot pulse. The output value of the DC voltage detector 22 that insulates and detects the terminal voltage of 4;
The output of the transformer 11 for detecting the voltage of the AC power supply 1 is input to the rectifier circuit 23 and compared with the average voltage value converted into the average voltage by the comparator 24, and the output value of the DC voltage detector 22 is the rectifier circuit 23. When it is larger than the output value and the one-shot pulse of the one-shot circuit 21 is being output, the AND circuit 25 operates to limit the DC voltage command value Vc of the charging self-exciting rectifier to “zero” by the limiting circuit 26. By limiting, the current setting value which is the input of the operational amplifier 14 becomes "zero", and the terminal voltage of the storage battery equipment is "zero" when the terminal voltage of the storage battery equipment is near the end-of-charge voltage when the charging self-exciting rectifier is started. It can be started while suppressing.

FIG. 2 is a control circuit diagram of a charging self-exciting rectifier according to a second embodiment of the present invention. In FIG. 2, the output value (V _IN ) of the transformer 11 that detects the voltage of the AC power supply 1 is divided by the output value (V _DC ) of the DC voltage detector 31 that insulates and detects the terminal voltage of the storage battery equipment 4. The arithmetic circuit 32 performs an operation for multiplying the divided value by the proportional constant K,
This is used as an input voltage waveform, and the deviation between the current setting value and the current detection value which is the output of the operational amplifier 14 is added to the input voltage waveform by the adder 15 to form a PWM control reference wave, so that the storage battery equipment is always provided. Since PWM control corresponding to the terminal voltage of 4 is performed, the regenerative power regenerated from the storage battery equipment 4 to the AC power source 1 via the charging self-exciting rectifier at the time of starting the charging self-exciting rectifier is suppressed. You can

[0014]

According to the present invention, even when a diesel power generation facility or the like is used as an AC power source and the other load of this diesel power generation facility is light, the generator of the diesel power generation facility does not fall into overspeed, While suppressing the cost increase of the self-exciting rectifying device for charging, this self-exciting rectifying device for charging can smoothly start up in a wide voltage range from the discharge end voltage to the end charge voltage of the terminal voltage of the storage battery equipment.

[Brief description of drawings]

FIG. 1 is a control circuit configuration diagram of a charging self-exciting rectifier according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a control circuit of a self-exciting rectifier for charging showing a second embodiment of the present invention.

FIG. 3 is a main circuit configuration diagram of a self-exciting rectifier for charging.

FIG. 4 is a control circuit configuration diagram of a self-exciting rectifier for charging showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... AC power supply, 2 ... AC reactor, 3 ... Self-exciting rectifier circuit, 4 ... Storage battery equipment, 11 ... Transformer, 12 ... Multiplier, 1
3 ... Current transformer, 14 ... Operational amplifier, 15 ... Adder, 16 ...
Carrier wave, 17 ... Comparator, 18 ... Pulse distributor, 21 ... One shot circuit, 22 ... DC voltage detector, 23 ... Rectifier circuit, 24 ... Comparator, 25 ... AND circuit, 26 ... Limiting circuit, 31 ... DC voltage detection Vessel, 32 ... Arithmetic circuit, Vc
... DC voltage command value.

Claims (2)

[Claims] 1. A method of controlling a self-exciting rectifier for charging, which supplies a charging voltage and a charging current to a storage battery facility in which a plurality of storage batteries are connected in series from an AC power source, wherein a terminal voltage of the storage battery facility and an average voltage of the AC power source are In comparison, when the terminal voltage is higher than the average voltage and within a predetermined time from the start of the charging self-exciting rectifier, the DC voltage command value of the charging self-exciting rectifier is limited to a predetermined limit value. A method for controlling a self-exciting rectifier for charging, comprising: 2. A method for controlling a self-exciting rectifier for charging, which supplies a charging voltage and a charging current to a storage battery facility in which a plurality of storage batteries are connected in series from an AC power source, in which a voltage of the AC power source is divided by a terminal voltage of the storage battery facility. To obtain an input voltage waveform, and add the deviation between the current setting value and the current detection value of the self-exciting rectifying device for charging to the input voltage waveform to form a reference wave for PWM control of the self-exciting rectifying device for charging. A method for controlling a self-exciting rectifier for charging, which is characterized.