CN201181845Y - Static Var Compensator Based on Fixed Point DSP - Google Patents

Abstract

The utility model discloses a static var compensator based on fixed-point DSP, which comprises a DSP controller, a current sampling circuit, a voltage sampling circuit, a signal conditioning circuit, an optical fiber drive circuit, an RS232/485 circuit, a thyristor switching capacitor group, and a thyristor Control the linear reactor, the input of the current sampling circuit and the voltage sampling circuit are respectively connected to the three-phase current and the three-phase voltage, the output of the current sampling circuit and the voltage sampling circuit are connected to the input of the signal conditioning circuit, and the signal conditioning circuit conditions the sampling signal Then it is sent to the DSP controller, and the DSP controller processes the sampling signal and then outputs the TSC control signal and TCR control signal. Cut capacitor bank, thyristor controlled linear reactor. The utility model has the advantages of small size and fast adjustment speed. Besides voltage stabilization and reactive power compensation, the utility model also has the functions of suppressing voltage flicker and unbalance.

Description

Static Var Compensator Based on Fixed Point DSP

technical field

The utility model relates to a reactive power compensation device, in particular to a static reactive power compensator based on fixed-point DSP.

Background technique

Modern power systems may have insufficient reactive power and excess reactive power under different operating modes. The loads of various power supply systems will also bring pollution and interference to the power supply system due to their nonlinearity and imbalance. Reactive power compensation. Reactive power compensation is an important means to maintain high-quality operation of the power grid. At present, capacitors connected in parallel with network inductive loads and advanced static var generators are mainly used in the field of reactive power compensation. Connecting capacitors in parallel with network inductive loads is a traditional method of compensating reactive power. Parallel capacitors have the advantages of simple structure, economy and convenience, can improve circuit parameters, reduce line inductive reactive power, compensate system reactive power, and improve voltage quality. The disadvantage is that the impedance is fixed or the level is fixed, and the reactive power demand change of the load cannot be tracked. It can only compensate the fixed reactive power, and it may also resonate with the system in parallel, resulting in harmonic amplification. The static var generator has the advantages of fast adjustment speed, wide adjustment range, small harmonic output, and strong reactive power adjustment ability under undervoltage conditions, but it is limited to the production and development level of power electronic devices. There are problems such as high technical difficulty and high cost.

Utility model content

In order to overcome the technical problems of the existing reactive power compensation device, which are too large in size, high in harmonic content, and small in operating range, the utility model provides a static wireless system based on fixed-point DSP control with fast adjustment speed, wide operating range, and small harmonic content. power compensator.

The technical solution of the utility model to solve the above-mentioned technical problems is: including DSP controller, current sampling circuit, voltage sampling circuit, signal conditioning circuit, optical fiber drive circuit, RS232/485 circuit, thyristor switching capacitor group, thyristor control linear reactor, The input of described current sampling circuit, voltage sampling circuit is respectively connected with three-phase current, three-phase voltage, and the output of current sampling circuit, voltage sampling circuit is connected with the input of signal conditioning circuit, and signal conditioning circuit is sent to DSP controller again to the conditioning of sampling signal , the DSP controller processes the sampling signal and then outputs TSC control signal and TCR control signal. Control the linear reactor.

In the above static var compensator based on fixed-point DSP, the thyristor-controlled linear reactor is a set of thyristor-controlled linear reactors connected in delta.

In the above static var compensator based on fixed-point DSP, the thyristor switching capacitor bank is composed of seven sets of single-tuned filters and one set of high-pass filters, and each set of filters is a three-phase three-wire star connection.

Beneficial effects of the utility model: the utility model adopts a TSC+TCR hybrid static compensator structure, the reactive power provided by the TSC is provided for rough adjustment, and then the reactive power provided by the TCR is finely adjusted for reactive power Dynamic continuous compensation, and can be continuously compensated in the range of inductance and capacitance; DSP is used as the main chip of the controller, the main circuit parameters are optimized and the adaptive fuzzy control strategy based on online learning is used; the drive circuit based on optical fiber is used, Misoperation caused by electromagnetic interference can be avoided. The adjustment speed of the device is fast, and the operating range is wide. After adopting measures such as optimized tuning and filtering technology, the content of harmonics in the compensation current is greatly reduced, and the volume and cost of the device are reduced. The reactive power compensation device adopting TSC+TCR hybrid structure, using intelligent control technology, can realize continuous adjustment of reactive power in the range of capacitive and inductive, and overcome the non-adjustable reactive power output of fixed capacitor banks and mechanical switching The capacitor bank has disadvantages such as graded output of reactive power output, slow response speed, impact of switching capacitor itself on the power grid, and limited service life of mechanical switches.

Below in conjunction with accompanying drawing and embodiment the utility model is described further.

Description of drawings

Fig. 1 is the overall block diagram of the utility model.

Fig. 2 is a block diagram of the main circuit of the utility model.

Detailed ways

As shown in Figure 1, the SVC system is mainly composed of DSP control board, TCR pulse generation board, TSC signal generation board, fiber conditioning conversion board, power pulse trigger board, delta-connected thyristor control reactor TCR and star-connected thyristor switching The capacitor bank TSC is formed, and the inductance L in the single-tuned filter composed of the capacitor C in the TSC is not shown. In the figure, the three-phase voltage and three-phase current of the transmission line (system compensation) or the three-phase current of the load (load compensation) are respectively connected to the signal conditioning board through the voltage sensor and the current sensor to convert them into signals acceptable to the DSP, and then Entering the A/D interface of the DSP, the DSP controller communicates with the host computer through the RS485 serial port on the board, obtains user control commands, processes the sampled data in different control modes, realizes SVC reactive power compensation, stabilizes voltage, and suppresses voltage flashes According to the corresponding functions, output high-precision trigger pulses, and convert the pulses into analog signals (TCR control angle voltage) or switching values (TSC switching instructions) as needed, and output them to TCR pulses. The generator board and the TSC signal generation board, and then through the optical fiber conditioning conversion board, use the optical fiber as the transmission medium to the power pulse trigger board to control the input and removal of the thyristor valve on the thyristor control reactor and the thyristor switching capacitor on the thyristor switching capacitor respectively.

As shown in Figure 2, the main circuit of the utility model is mainly composed of 8 sets of star-connected thyristor switching capacitor banks and a set of delta-connected thyristor-controlled linear reactors, wherein the capacitors in the capacitor banks have 7 sets of capacitors C, a set of capacitors is C/2, so that 16 levels of segmental capacitive reactive power can be output, which increases the speed and can filter out the 2nd, 3rd, 4th, 5th, 6th, 7th, 8th and 11th harmonics respectively The thyristor-controlled reactor TCR can absorb inductive reactive power, and the reactive power of the two can be continuously adjusted between positive and negative, so as to overcome the disadvantage of non-adjustable reactive power of the fixed capacitor bank.

Claims (3)

1, a kind of Static Var Compensator based on fixed DSP, it is characterized in that: comprise dsp controller, current sampling circuit, voltage sampling circuit, signal conditioning circuit, optical fiber driving circuit, the RS232/485 circuit, the thyristor switchable capacitor group, thyristor control linear reactor, described current sampling circuit, the input of voltage sampling circuit connects three-phase current respectively, three-phase voltage, current sampling circuit, the output of voltage sampling circuit connects the input of signal conditioning circuit, signal conditioning circuit is nursed one's health sampled signal and is delivered to dsp controller again, dsp controller is handled back output TSC control signal to sampled signal, the TCR control signal, the TSC control signal, the TCR control signal is delivered to optical fiber driving circuit after the signal conditioning circuit conditioning, deliver to the thyristor switchable capacitor group by optical fiber again, thyristor control linear reactor.

2, the Static Var Compensator based on fixed DSP according to claim 1 is characterized in that: described thyristor control linear reactor is the thyristor control linear reactor that a cover triangle connects.

3, the Static Var Compensator based on fixed DSP according to claim 1 is characterized in that: described thyristor switchable capacitor group is that seven cover single tuned filters and a cover high pass filter are formed, and every cover filter is the wye connection of three-phase three-wire system.

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