JP2645172B2 - Rotary type interconnection system - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial application field) The present invention relates to a rotary interconnection device for interconnecting power systems.

(Prior Art) Conventionally, as a rotary interconnection device, a synchronous motor 101A and a synchronous generator 101B are directly connected by a direct connection shaft 102 as shown in FIG. There is a synchronous frequency converter of the so-called constant-ratio frequency conversion type, which is selected equally. This converter includes an armature moving device 105 that can move one of the armatures in the circumferential direction to adjust the load angle in order to control the passing power. Since the armature moving device 105 operates mechanically,
Originally, high-speed control of passing power is impossible, and it is useless when urgent power interchange in a power system is required. In the figure, 103A and 103B are automatic voltage regulators (AVR), 104
A and 104B are field windings.

(Problem to be Solved by the Invention) When a supply-demand imbalance occurs in one of the interconnected power systems, and when an emergency interchange from the other power system is required due to problems of system stability and frequency fluctuation, a rotary interconnection device is required. However, if high-speed control of the passing power is possible, it is preferable from the viewpoint of stable operation of the system.

(Object of the Invention) The present invention has been made to meet the above-mentioned demands, and an object of the present invention is to provide a rotary grid interconnection device that enables high-speed power control.

[Structure of the Invention] (Means for solving the problem) The winding induction machine uses a frequency converter such as a cycloconverter to apply a slip frequency of a difference between a frequency on a power system side and a rotor frequency to a secondary winding thereof. The generation or consumption of the active power and the reactive power can be controlled at high speed by flowing the secondary current and controlling the magnitude and phase thereof. That is, even if the rotational speed of the rotor changes, the cycloconverter is controlled to always follow the frequency of the secondary current as the slip frequency, and at the same time, the magnitude and phase of the secondary current can be controlled at high speed if necessary. The magnitude of the magnetic flux of the secondary circuit and the phase angle with respect to the armature circuit side can be quickly adjusted, and as a result, instantaneous control of electric power with the system side can be performed. A system including such a winding-type induction machine, a cycloconverter, and a control device having such a function is generally referred to as an AC variable-speed machine. By directly connecting the shafts and controlling the frequency converters such as cycloconverters individually, not only realizes the same passing power adjustment function as the armature moving device in the case of the synchronous synchronous frequency converter at high speed, Electric energy can be stored in place of the inertial energy of the rotating machine, which can contribute to system operation.

(Operation) The difference from the case of the conventional mechanically operated synchronous synchronous frequency converter is that the magnitude of the internal induced voltage created by the magnetic flux of the rotor secondary circuit by the cycloconverter control instead of the armature moving. Since electric control is performed at the point where the phase changes, electric power can be individually adjusted at high speed on each rotating machine side. At the same time, the terminal voltage of the wound induction machine can be adjusted.

(Examples) Hereinafter, the present invention will be described based on examples.

 FIG. 1 is a configuration diagram of one embodiment of the present invention.

In FIG. 1, the AC variable speed machine on the system A side is distinguished by adding A after the number, and the AC variable speed machine on the system B side is distinguished by adding B after the number. A or B attached after the number is simply a symbol for distinguishing two AC variable speed machines, and the same number means the same device or physical quantity.

Here, 1A and 1B are wound type induction machines, and 2 is a wound type induction machine 1A
And 1B are rotary shafts (hereinafter referred to as direct-coupled shafts for convenience) mechanically coupled so as to make the same rotation. In addition, 3A and 3B are AC excitation windings wound on the rotor side, and 4A and 4B are frequency converters, which control the magnitude, phase and frequency of the AC excitation current flowing through the AC excitation windings 3A and 3B, respectively. I do. 5A and 5B are power transformers for the frequency converters 4A and 4B, respectively. 6
A and 6B are power detectors for detecting the power output of the winding type induction machines 1A and 1B, 7A and 7B are power detection signals of the outputs of the power detectors 6A and 6B, and 8A and 8B are for power control. The target power signals 9A and 9B are power control devices that compare the power detection signals 7A and 7B with the target power signals 8A and 8B and control the power by the frequency converters 4A and 4B when there is an error. 10A and 10B are power control signals of the power control devices 9A and 9B. 12A and 12B are referred to as voltage control devices. The voltage detection signals 11A and 11B detected from the terminals of the winding type induction machines 1A and 1B and the target voltage signals 13A and
3B are compared with each other, and if there is an error, voltage control is performed by the frequency converters 4A and 4B. 14A and 14B are voltage control signals of the voltage control devices 12A and 12B. The frequency converters 4A and 4B have power control signals 10A and 10B and voltage control signals 14A and
The power of the winding type induction machines 1A and 1B and the voltage of the terminals are controlled based on the two control signals of 14B, and the control of the rotation speed of the rotor of the winding type induction machines 1A and 1B is necessary for the control. For detection, rotation speed detection signals 16A, 16B of the resolvers 15A, 15B,
Voltage detection signals 11A and 11B are input for phase detection of the terminal voltage.

2 is compared with the present invention shown in FIG. 1, the present invention shows that the synchronous machine 101A and the synchronous machine 101B are directly connected to each other and the synchronous machine
Instead of the system consisting of the armature moving device 105 installed in 101B, two winding type induction machines in which voltage control and power control are individually performed by frequency converters 4A and 4B, respectively.
It can be seen that 1A and 1B are systems directly connected to the axis.

In the embodiment configured as described above, the winding type induction machine 1
If the terminal voltage change of A, 1B or the change of power, that is, an error from the respective target value occurs during operation, the power control signals 10A, 10B and the voltage control signals 14A, 14B are supplied to the frequency converters 4A, 4B, respectively. The frequency converters 4A and 4B detect the magnitudes of the AC excitation current flowing through the AC excitation windings 3A and 3B and the phase with respect to the terminal voltage based on the signals, thereby detecting the voltage detection signals 11A and 11B.
At the same time as controlling based on B, the slip frequency is calculated from the voltage detection signals 11A and 11B and the rotation speed detection signals 16A and 16B,
Control is performed so that the frequency of the AC exciting current flowing through the AC exciting windings 3A and 3B always follows this slip frequency. As a result, the magnitude and phase of the internal induced voltage generated by the magnetic flux of the rotor secondary circuit can be controlled at a high speed, so that the terminal voltage can be adjusted by changing the magnitude and the power can be adjusted by changing the phase. Can be done quickly. Here, if the target power signals 8A, 8B are constant values, the power of the wound induction machines 1A, 1B is controlled to be constant by the power control as described above.

In the system interconnection device configured as shown in FIG.
The transmission and reception of power from the system to the system B can be realized by controlling as follows. That is, if the direction in which the polarity of the target power signals 8A and 8B is sent from each of the wound induction machines to the system is positive,
If the amount of passing power from the system A to the system B is, for example, Pc, the target power signals 8A and 8B are set as follows.

Target power signal 8A P ^* =-Pc Target power signal 8B P ^* =-Pc If the following settings are made, power will be received from both the system A and the system B, and as a result, this system interconnector will rotate. Electric energy can be absorbed as rotational energy by the inertia of the machine.

Target power signal 8A P ^* =-Pc Target power signal 8B P ^* =-Pc Here, if the polarity of both target power signals is set to +, power energy can be released conversely.

[Effects of the Invention] As described above, according to the embodiment, instead of the two synchronous machines of the conventional rotary system interconnection device, both the rotating machines are used as the winding type induction machines, and the respective frequency converters are used. The AC excitation current flowing in the AC excitation winding of the wound induction machine is controlled individually and at high speed, so that the transfer of power between systems can be performed at high speed according to the setting of each target power signal. A controllable rotary system interconnection device can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a block diagram of a conventional synchronous frequency converter. 1A, 1B ... winding type induction motor, 2 ... direct connection shaft 3A, 3B ... AC excitation winding 4A, 4B ... frequency converter 6A, 6B ... power detector 9A, 9B ... power controller 12A, 12B …… Voltage controller 15A, 15B …… Resolver

Claims (1)

(57) [Claims] An armature winding of each of a first and a second winding type induction machine is interconnected with a first and a second power system of a different system, and an AC excitation winding is wound around each of the armature windings. First and second frequency converters are provided for mechanically coupling the rotors so as to rotate in the same manner, and for controlling the magnitude, phase, and frequency of the AC exciting current flowing through each of the AC exciting windings. A first and a second detecting means provided on the first and second winding type induction machines, respectively, for detecting power and voltage at each armature winding terminal; The power detection signal and the voltage detection signal output from the first and second detection means
And a first and second power control device for comparing a target power signal and a target voltage signal individually set on the side of the second winding type induction machine and outputting an error as a power control signal and a voltage control signal; And a second voltage control device, and first and second resolvers provided on the first and second winding type induction machines, respectively, for detecting the rotational speeds of the respective rotors. The power control signal, the voltage control signal, the rotation speed detection signal and the voltage detection signal from the resolver are input to the frequency conversion device to individually control the power and terminal voltage of the first and second winding induction machines. A rotary system interconnection device that can be used.