CN103208851A - Vertical-axis wind power converter device - Google Patents

Abstract

The utility model relates to a vertical-axis wind power generation conversion device, which belongs to the field of wind power generation. It includes vertical axis wind turbine, unloading resistor box, three-phase relay, uncontrolled rectifier bridge, energy storage capacitor bank and its pre-charging circuit, 1# current sensor, 1# voltage sensor, power device VT ₁ , fast recovery diode D ₁ , high frequency inductance L, power device VT ₂ , diode D ₂ , filter capacitor C ₂ , power device VT ₃ , energy dissipation resistor R ₂ , 2# current sensor, 2# voltage sensor, battery pack. It switches between different working modes in real time under different wind speed conditions. When the wind speed is low, it works in the boost mode, and when the wind speed is high, it works in the step-down mode, so as to make maximum use of the output power of the wind turbine and fully convert the wind energy into DC power. Charging the storage battery realizes new energy wind power generation and its utilization. The invention is suitable for small and medium-sized independent vertical axis wind power generating sets.

Description

A vertical axis wind power converter device

technical field

The invention relates to an AC/DC conversion device for power generation, in particular to a converter device for vertical axis wind power generation.

Background technique

As a clean and renewable energy, wind energy is an important project in the development of new energy. my country's overall wind energy resources are relatively rich, but the distribution is uneven. In many mountainous areas, farming areas and pastoral areas, the wind speed is low and unstable all year round, which does not meet the site selection requirements for wind farms. Therefore, it is necessary to vigorously promote small and medium-sized wind turbines. Small-scale wind power generation systems that operate independently do not have high requirements for starting wind speed. Generally, wind speeds above 3m/s can operate normally to generate electricity. With the energy storage and release of lead-acid batteries, it can ensure the normal power consumption of small and medium power equipment. Compared with the horizontal-axis wind turbine, the gearbox of the vertical-axis wind turbine is at the bottom of the whole machine, and the center of gravity is low. The impeller is directly connected to the rotor of the generator through the rotating shaft, and does not need a windward adjustment system. It can accept wind from any direction and improve It improves the utilization rate of wind energy, and has a simple structure, convenient installation and maintenance, low cost, and has a very broad application prospect.

Due to the instability of wind speed, if the AC power generated by the generator is directly charged to the battery through an uncontrolled rectifier bridge, the minimum charging voltage requirement cannot be reached when the wind speed is low; when the wind speed is high, the generator outlet voltage is clamped to the battery terminal voltage On the other hand, the output power of the generator is small, which greatly wastes the wind energy. Therefore, it is of great practical significance to study a flow conversion device suitable for fully utilizing wind energy at different wind speeds.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art, solve the problem that it is difficult for small and medium-sized vertical-axis wind power generators to fully utilize wind energy and achieve maximum power output under different wind speed conditions, and provide a vertical-axis wind power converter device. It is an independent power supply device that can maximize the use of the output of the generator and realize AC-DC conversion under both low wind speed and high wind speed conditions.

The technical scheme adopted in the present invention is:

The invention relates to a vertical axis wind power conversion device, which includes a main circuit part and a control circuit part. The main circuit includes: vertical axis wind turbine, unloading resistance box, three-phase relay, uncontrolled rectifier bridge, energy storage capacitor bank and its pre-charging circuit, 1# current sensor, 1# voltage sensor, power device VT ₁ , Fast recovery diode D ₁ , high frequency inductor L, power device VT ₂ , diode D ₂ , filter capacitor C ₂ , power device VT ₃ , energy consumption resistor R ₂ , 2# current sensor, 2# voltage sensor, battery pack.

The vertical axis wind power generation conversion device described above, in its main circuit, the outlet end of the vertical axis wind power generator is connected to the uncontrolled rectifier bridge, and the alternating current is rectified into direct current to charge the energy storage capacitor bank, and the 1# voltage sensor measures the capacitor The group terminal voltage, the 1# current sensor measures the bus current, the power device VT ₁ , the fast recovery diode D ₁ and the high-frequency inductor L form a step-down chopper circuit, which performs chopping processing on the bus voltage. At the same time, the high-frequency inductor L and the power device VT ₂ , diode D ₂ , and filter capacitor C ₂ form a step-up chopper circuit to charge the battery pack. 2# current sensor and 2# voltage sensor measure the charging current and voltage of the battery pack respectively, and the power device VT ₃ and energy consumption Resistor R ₂ forms an energy consumption protection circuit to prevent the battery from overcharging. When the wind speed is too high, relay K ₁ connects the generator winding to the unloading resistor box for unloading brake protection.

The control circuit of the vertical-axis wind power conversion device includes: an anemometer, a controller, a PWM1 isolation drive, a PWM2 isolation drive, a charging protection signal drive, and an unloading protection signal drive.

In the described vertical axis wind power conversion device, the controller in the control circuit receives the output signals of the anemometer, 1# current sensor, 1# voltage sensor, 2# current sensor, and 2# voltage sensor, and the software control algorithm Afterwards, two pulse signals are outputted through PWM1 isolation drive and PWM2 isolation drive to control the power device VT ₁ and power device VT ₂ ; when the charging protection condition is reached, the output switching signal is driven by the charging protection signal to control the power device VT ₃ . Put the energy consumption resistor _R2 into operation; after the wind speed is too high to meet the unloading braking condition, the output switch signal is driven by the unloading protection signal and connected to the relay, and the unloading resistance box is put into operation.

The voltage sensor is a Hall-type voltage sensor, and the current sensor is a Hall-type current sensor.

The power device VT1, power device VT2, and power device VT3 are IGBTs, and adopt RC type snubber circuits.

The battery pack is composed of four 12V valve-regulated sealed lead-acid batteries connected in series to form a 48V DC power supply.

The controller is a PIC microcontroller.

The wind speed meter is HL-FS2 wind speed sensor.

The advantage of the present invention is that: when the wind speed is low, the inverter device acts as a step-up chopper, and when the wind speed is high, the inverter device acts as a step-down chopping wave, and the alternating current generated by the generator can be converted into direct current for the storage battery under different wind speeds. group charging. According to the rated voltage of the connected battery pack and the actual wind speed, the working mode of step-up/step-down is dynamically switched. The control software contains the maximum power tracking control algorithm to realize the maximum power output of the generator under high wind speed. The whole device realizes the maximum utilization of wind energy when the wind speed is above 3m/s.

Description of drawings

Fig. 1 is the main circuit structure diagram of the device of the present invention.

Fig. 2 is a control circuit structure diagram of the device of the present invention.

Fig. 3 is a flowchart of the maximum power control algorithm in the present invention.

Fig. 4 is the voltage and current waveforms of the VT ₂ terminal in the boost working mode of the device of the present invention at a wind speed of 3m/s.

Fig. 5 is the voltage and current waveforms of the battery charging by the device of the present invention.

Detailed ways

The embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. This embodiment is based on the technical solution of the present invention and provides specific implementation methods and detailed operating procedures, but the scope of protection of the present invention is not limited to the following implementations. example.

Embodiment 1: In this embodiment, in the case of a low wind speed of 3m/s, the device of the present invention converts wind energy into electrical energy and stores it in the storage battery pack. This embodiment will be described in conjunction with Fig. 1 and Fig. 2 from bottom to top. When the wind speed is 3m/s, the line voltage of the wind turbine winding is 16.5V, the bus voltage is 38.6V after being rectified by the uncontrolled rectifier bridge, and the terminal voltage of the battery pack is 48V, which cannot directly charge the battery. At this time, the converter device works In boost mode, the battery is charged after the bus voltage is boosted. The power device VT ₁ is always on, and the power device VT ₃ is always off. Based on the data detected by the 1# voltage sensor and the 2# voltage sensor, the software adjusts the conduction duty ratio of the power device VT ₂ in real time, so that the two The terminal voltage is maintained between 52 and 60V. At this time, in the device, the high-frequency inductor L, the power device VT ₂ , the diode D ₂ and the filter capacitor C ₂ form a step-up chopper circuit, which raises the rectified DC voltage to a preset range to realize charging and energy storage of the battery . Figure 4 shows the voltage and current at both ends of the power device VT ₂ in this working mode.

Specific embodiment 2: In this embodiment, when the wind speed is higher than 5m/s, the device of the present invention converts wind energy into electrical energy and stores it in the battery pack. This embodiment will be described in conjunction with Fig. 1 and Fig. 2 from bottom to top. As the wind speed increases, the line voltage of the generator winding increases accordingly. When the wind speed reaches 5m/s, the bus voltage greatly exceeds the healthy charging voltage range of the battery pack (52-60V) after passing through the uncontrolled rectifier bridge. At this time, the converter works in the step-down mode to charge the battery after reducing the bus voltage to the healthy charging voltage range. The power device VT ₂ is constantly turned off, and the power device VT ₃ is turned off. Through the data detected by the 1# voltage sensor and the 2# voltage sensor, the conduction duty cycle of the power device VT ₁ is adjusted in real time in the software, so that both ends of the battery pack The voltage is maintained between 52 and 60V. At this time, in the device, power device VT ₁ , fast recovery diode D ₁ , high-frequency inductor L, diode D ₂ , and filter capacitor C ₂ form a step-down chopper circuit, which reduces the rectified DC voltage to a preset range, realizing Charge the storage battery. The charging voltage and charging current of the battery are detected by the 2# current sensor and the 2# voltage sensor. When the charging is completed or reaches the charging current protection value, the controller outputs a switching signal to turn on the power device VT ₃ , and puts in the energy consumption resistor R ₂ to charge the battery. protection against overcharging. Figure 5 shows the terminal voltage and charging current of a single battery in this working mode.

Specific Embodiment Three: In this embodiment, in the case of high wind speed, in order to maximize the output power of the generator, the maximum power tracking algorithm is used in the software to optimize the conduction duty cycle of the power device VT ₁ , so that the battery is healthy Within the charging voltage range, the charging current reaches the maximum. This embodiment will be described below with reference to FIG. 3 . 2# voltage sensor and 2# current sensor respectively measure the charging voltage and charging current of the battery, and then judge whether the charging voltage and charging current exceed the maximum limit value. As long as one of the two exceeds the limit value, the charging protection function is activated, and the power device VT ₃ is turned on, and the energy consumption resistor R ₂ is put into it. If not, use the 1# current sensor and 1# voltage sensor to detect the bus voltage and current respectively, and calculate the output power of the motor at this time. Comparing the calculation result with the result obtained at the last sampling time, the constant step-size perturbation is continuously optimized for the conduction duty cycle of the power device VT ₁ according to different situations. During this process, if it is detected that the output voltage of the generator exceeds the preset limit value, it means that the wind speed is too high. In order to protect the converter device and the generator, the unloading brake protection is performed, and the controller outputs the unloading protection signal through the drive circuit and the relay K ₁ Action, put into the unloading resistance box, unloading protection for the whole device.

Claims (9)

1. vertical axis wind power generation convertor assembly, it comprises main circuit and control circuit, and wherein main circuit comprises: vertical axis aerogenerator (1), off-load resistance box (2), three phase relaies (3), do not control rectifier bridge (4), energy storage capacitor group and pre-charge circuit (5) thereof, 1# current sensor (6), 1# voltage sensor (7), power device VT ₁(8), fast recovery diode D ₁(9), power device VT high-frequency inductor L(10), ₂(11), diode D ₂(12), filter capacitor C ₂(13), power device VT ₃(14), power consumption resistance R ₂(15), 2# current sensor (16), 2# voltage sensor (17), batteries (18).

2. vertical axis wind power generation convertor assembly; it comprises main circuit and control circuit, and wherein control circuit comprises: anemobiagraph (19), controller (20), PWM1 isolation drive (21), PWM2 isolation drive (22), charge protection signal drive (23), the off-load guard signal drives (24).

3. a kind of vertical axis wind power generation convertor assembly according to claim 1, it is characterized in that: described vertical axis aerogenerator (1) leading-out terminal with do not control rectifier bridge (4) and link to each other, after AC rectification become direct current energy storage capacitor group (5) is charged, 1# voltage sensor (7) is measured capacitor group terminal voltage, 1# current sensor (6) is measured bus current, power device VT ₁(8) with fast recovery diode D ₁(9), high-frequency inductor L(10) form chopper circuit, busbar voltage is carried out copped wave handles, simultaneously high-frequency inductor L(10) and power device VT ₂(11), diode D ₂(12), filter capacitor C ₂(13) form boost chopper batteries (18) is charged, 2# current sensor (16) and 2# voltage sensor (17) are measured batteries (18) charging current and charging voltage, power device VT respectively ₃(14) and the power consumption resistance R ₂(15) form the power consumption protective circuit and prevent accumulator super-charge, relay K when wind speed is excessive ₁(3) generator windings is linked to each other with off-load resistance box (2), carry out off-load brake protection.

4. according to claim 1 and 2 described a kind of vertical axis wind power generation convertor assemblys, it is characterized in that: controller (20) receives the output signal of anemobiagraph (19), 1# current sensor (6), 1# voltage sensor (7), 2# current sensor (16), 2# voltage sensor (17), behind software control algorithm the output two pulse signals respectively through PWM1 isolation drive (21), PWM2 isolation drive (22) to power device VT ₁(8) and power device VT ₂(11) control; After reaching the charge protection condition, output switching signal drives (23) control power device VT through the charge protection signal ₃(14), the resistance R that will consume energy ₂(15) put into operation; Wind speed is excessive reach off-load brake condition after, output switching signal drives (24) through the off-load guard signal and is connected with relay (3), and off-load resistance box (2) is put into operation.

5. a kind of vertical axis wind power generation convertor assembly according to claim 1, it is characterized in that: described voltage sensor is the Hall-type voltage sensor, current sensor is the Hall-type current sensor.

6. according to the described a kind of vertical axis wind power generation convertor assembly of claim 1, it is characterized in that: described power device VT ₁(8), power device VT ₂(11), power device VT ₃(14) be IGBT, adopt RC type buffer circuit.

7. a kind of vertical axis wind power generation convertor assembly according to claim 1, it is characterized in that: described batteries is that 4 12V valve controlled sealed lead-acid accumulators are composed in series the 48V DC power supply.

8. a kind of vertical axis wind power generation convertor assembly according to claim 2, it is characterized in that: described controller is the PIC single-chip microcomputer.

9. a kind of vertical axis wind power generation convertor assembly according to claim 2, it is characterized in that: described anemobiagraph is the HL-FS2 air velocity transducer.

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